2021 AATS专家共识：急性A型主动脉夹层的手术治疗

2021 The American Association for Thoracic Surgery expert consensus document: Surgical treatment of acute type A aortic dissection

a b a c S. Christopher Malaisrie, MD, Wilson Y. Szeto, MD, Monika Halas, MD, Leonard N. Girardi, MD, d e f g Joseph S. Coselli, MD, Thoralf M. Sundt III, MD, Edward P. Chen, MD, Michael P. Fischbein, MD, PhD, h i j k Thomas G. Gleason, MD, Yutaka Okita, MD, Maral Ouzounian, MD, PhD, Himanshu J. Patel, MD, l m l Eric E. Roselli, MD, Malakh L. Shrestha, MD, PhD, Lars G. Svensson, MD, PhD, and n Marc R. Moon, MD, the AATS Clinical Practice Standards Committee: Adult Cardiac Surgery

Acute aortic dissection (AD) involves the ascending aorta in 1 , 2 approximately two-thirds of patients. Chest pain is the most common feature, but clinical presentation can be varied, and algorithms have been developed to facilitate timely 3 , 4 diagnosis. Nevertheless, delays in diagnosis comes at a 5 severe cost to the patient. The complications of AD that involve the ascending aorta have been known for well over 60 years and include aortic rupture, cardiac tampo6 , 7 nade, aortic regurgitation (AR), and organ malperfusion.

The risk of death is estimated to be $1\%$ to $2\%$ per hour and nonoperative treatment is associated with mortality in nearly $60\%$ of patients. 8 , 9 Open surgical repair of the ascending aorta is a life-saving operation and remains the standard of care for patients with acute type A AD (ATAAD). The surgical care of these patients continues to evolve through innovation, guided by clinical evidence with long-term follow-up.

Our goal was to develop an expert consensus document (ECD) for the surgical treatment of ATAAD. The intent of this ECD is to improve quality of care through evidence

 Surgical treatment of acute type A aortic dissection.

CENTRAL MESSAGE

The management of ATAAD continues to evolve but emergency cardiac surgery remains the standard of care.

PERSPECTIVE

Acute, type A aortic dissection remains a challenging emergency in cardiovascular surgery. The management of life-threatening complications has evolved to include endovascular options and complex aortic repair, but expeditious open replacement of the ascending aorta remains the preferred approach. This expert consensus offers recommendations based on current clinical evidence and expert opinion.

See Commentary on page XXX.

based recommendations for a true surgical emergency. These recommendations, on the basis of systematic methods to evaluate and classify evidence, should serve surgeons, emergency room physicians, and any health care provider who care for patients with ATAAD.

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Abbreviations and Acronyms AATS $=$ The American Association for Thoracic Surgery ACP $=$ AD $=$ aortic dissection AR $=$ aortic regurgitation ATAAD $=$ acute type A aortic dissection CAC $=$ ¼ comprehensive aortic center CPB $=$ cardiopulmonary bypass CT $=$ computed tomography ECD $=$ FET $=$ ¼ frozen elephant trunk HTAD $=$ IMH $=$ intramural hematoma IRAD $=$ ¼ International Registry for Aortic Dissection MRI $=$ RCP $=$ retrograde cerebral perfusion SCI $=$ spinal cord injury STS $=$ Society of Thoracic Surgeons TEVAR ¼ thoracic endovascular aortic repair TTE $=$ VSARR ¼ valve-sparing aortic root replacement

Definitions and Scope

1. AD is a disruption of the tunica intima that results in blood flow into the tunica media that can propagate throughout the entire length of the aorta and into branch vessels. AD is part of a spectrum of acute aortic syndromes including penetrating aortic ulcer and intramural hematoma (IMH). These syndromes are life-threatening, inter-related conditions with similar clinical characteristics.

2. Type A AD involves the ascending aorta (proximal to brachiocephalic artery), regardless of primary entry tear location according to the Stanford classification and are also considered type I/type II AD depending on the distal extent according to the DeBakey classifica7 ,10.11 tion. Newer classifications endorsed by surgical societies have characterized AD according to site of primary entry tear, extent of false lumen, and malperfu12 , 13 sion. Standardization of these classifications has not been uniform, and definitions have been conflicting. For example, an AD with the primary entry tear in the proximal descending thoracic aorta with proximal extension of the false lumen into the ascending aorta (retrograde type A AD according to the Stanford definition) would be classified as a type B AD according to the Society of Thoracic Surgeons (STS)/Society for Vascular Surgery definitions and a type A AD according to the Eu

ropean Association for Cardio-Thoracic Surgery/Euro12 , 14 pean Society of Cardiology definitions.

3. ATAAD is a dissection that is diagnosed ${<}14$ days from the onset of symptoms and is standard in all classifica4 , 12 , 15 tion schemes. For the purposes of this document, any AD that involves the ascending aorta (proximal to the brachiocephalic artery) and is diagnosed within 14 days of symptom onset are considered ATAAD regardless of the location of the primary entry tear. Subacute and chronic AD are beyond the scope of this document.

4. The scope of this document is the management and treatment of ATAAD. A detailed review of the evaluation and diagnosis was not performed.

5. Although surgical management is the main focus of this document, concise perioperative medical management and postoperative follow-up are included.

6. The writing group acknowledges and endorses the evidence-based approaches to ATAAD management including the 2010 American College of Cardiology Foundation/American Heart Association/The American Association for Thoracic Surgery (AATS)/American College of Radiology/American Stroke Association/Society of Cardiovascular Anesthesiologists/Society for Cardiovascular Angiography and Interventions/Society of Interventional Radiology/STS/Society for Vascular Medicine guidelines for the diagnosis and management of patients with thoracic aortic disease, 2011 Japanese Circulation Society guidelines for diagnosis and treatment of aortic aneurysm and aortic dissection, 2014 European Society of Cardiology guidelines on the diagnosis and treatment of aortic diseases, and the 2016 Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/Canadian Society for Vascular Surgery joint position statement on open and endovascu3 , 4 , 16 , 17 lar surgery for thoracic aortic disease.

7. Patient preferences and values should be combined with evidence-based, clinical judgment in the management of ATAAD.

8. When new data become available, the recommendations in this document are subject to revisions.

METHODOLOGY

We followed the recommendations of the AATS/STS position statement 1 on developing clinical practice documents. An expert panel consisting of 15 cardiac surgeons, all members of AATS, followed an ECD pathway to develop consensus statements according to class of recommendation and the level of evidence. Class of recommendation specifies the strength of recommendation, including the estimated magnitude and certainty of benefit compared with risk, and level of evidence is used to assesses the quality of scientific evidence supporting the recommendation, graded on the basis of the type, quantity, and consistency of the data from clinical tri2 als and other sources.

Literature searches were conducted by a scholarly communications librarian using Ovid MEDLINE, and all articles published since 2000

were reviewed ( Appendix E1 ). Important, older landmark publications were also included. After these initial searches, section-specific literature was reviewed by the writing committee and recommendations were created on the basis of discussion, overseen by an epidemiologist/methodologist. Recommendations were submitted for voting among writing committee members. To approve recommendations, a $75\%$ consensus rate was required with $80\%$ participation to ensure validity of voting. This process was repeated for each section. Controversies were discussed and resolved via regular, online video meetings and re-voting, in accordance with the 3 , 4 Delphi method process. Each author contributed substantially to the writing of 8 document sections and the document was finalized by the writing committee chairs. The writing committee and a group of 10 external reviewers were given an opportunity to review, comment, and approve the document before it was submitted for final approval by AATS Cardiac Clinical Practice Standards Committee and AATS Board of Directors.

## SECTION 1: INITIAL MEDICAL THERAPY

Initial medical therapy ( Table 1 ) should optimize patient stabilization during interhospital transfer and surgical triage. As soon as a diagnosis of ATAAD is made, treatment of blood pressure, pulse rate, and pain should be initiated. Medical therapy should be directed at decreasing excessive shear stress on the dissected layers of the affected aorta, thereby reducing false lumen propagation. Additionally, patients with ATAAD can present with various complications, such as severe AR, hypotension, and cardiac tamponade. Hence, the choice of medical treatment should be individualized to the presenting clinical condition to minimize exacerbation of ATAAD complications. Medical treatment is not a substitute for surgery, but used appropriately, can be crucial in achieving initial stabilization.

Focused Clinical Questions

What are appropriate agents for anti-impulse therapy? Goals of initial medical therapy in normotensive or

hypertensive patients should be focused on decreasing shear stress on the aortic wall, suppression of false lumen propagation, and ultimately prevention of rupture. Forces acutely propagating the dissection process include the heart rate, blood pressure, and velocity of ventricular contraction. These parameters might be stabilized through early $\beta\cdot$ - blockade to systolic blood pressure targets of 100 to $120\ \mathrm{mm\Hg}$ and heart rate below 60 bpm. 11-13 Through diminished afterload and decreased rate of oxygen consumption, anti-impulse therapy also provides improvement in myocardial perfusion. Exemplary agents are intravenous propranolol, esmolol, labetalol, or metoprolol. Esmolol has a uniquely short half-life, and labetalol, a $\beta$ -blocker with intrinsic partial sympathomimetic activity, gives a potent advantage of achieving heart rate and blood pressure control, potentially reducing the need for additional agents. Some of the contraindications to $\beta$ -blockers are asthma, chronic obstructive pulmonary disease, or atrioventricular block. Potential alternatives in patients with contraindications or in those not able to tolerate $\beta$ -blockers are nondihydropyridine calcium channel blockers—verapamil or diltiazem. Both drugs should be used with caution in a setting of severe AR because they might cause reflex tachycardia.

TABLE 1. Initial medical therapy recommendations

|Recommendations COR LOE References|||| |---|---|---|---| |Initial Medical Therapy|||| | B-blockers are recommended in the initial management of ATAAD without severe aortic regurgitation. |||1-③| |NI Calcium channel blockers are a potential alternative.|na||1,3,4| | ③1 When multiple agents are required, it is reasonable to start vasodilators after initial rate control. |ma||1，③| | In the setting of hypotension, volume resuscitation is reasonable to achieve systolic blood pressure of 90 mmHg. |na||5-7| |Pain relief is recommended in patients with ATAAD.||C|8-10|

What are appropriate second-line agents? Additional agents might be required when hypertension is refractory to one agent. Vasodilators should be used with caution, ensuring chronotropic control with $\beta$ -blockers is first estab3 lished, to avoid reflex tachycardia. Intravenous nicardipine (dihydropyridine calcium channel blocker) has been shown to rapidly decrease blood pressure, without reflex tachy4 cardia or exaggerated depression of diastolic pressure. Intravenous nitroprusside has also been effectively used in

a setting of acute AD, however, cyanide toxicity during prolonged administration is a serious adverse effect. Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers are also reasonable options, but more difficult to titrate.

How should hypotension in patients with ATAAD be managed? Hypotension in ATAAD patients is a critical condition, associated with increased in-hospital mortality 6 , 7 and neurologic events. Underlying causes include acute AR, cardiac tamponade, and myocardial infarction. Each of these conditions require definitive operative management. The most reasonable first approach is to administer intravenous fluids to improve blood pressure, increase preload and cardiac output, and ensure adequate end-organ perfusion. Permissive hypotension is reasonable with a target systolic pressure of $90\,\mathrm{mm\,Hg}$ , because mortality in5 , 6 creases below that value. Vasopressors might be an adjunct to volume therapy but can contribute to further propagation of false lumen. Pericardiocentesis remains controversial in dissection-related hemopericardium and should not delay surgery. However, in patients with imminent cardiac arrest, hemopericardium may be treated with pericardiocentesis to restore sufficient end-organ 14 perfusion.

How to manage pain in patients with ATAAD? Patients 8 , 9 with ATAAD might present with acute pain and anxiety. Pain affects the sympathetic system, increasing blood pressure and heart rate through the release of catecholamines, which directly undermines anti-impulse therapy. Analgesia augments the effects of $\beta$ -blockers and vasodilators, and opioids provide not only beneficial effects on anti-impulse therapy, but also decrease agitation and respiratory distress. Intravenous opioids should be started early after the diagnosis and rapidly titrated for pain relief.

SECTION 2: INTERHOSPITAL TRANSFER

Current data suggest that ATAAD patients might benefit from transfer to a comprehensive aortic center (CAC). The metrics to define such centers is beyond the scope of this

document but might include case volume and expertise in emergency and elective aortic cases. Surgery for ATAAD is an uncommon occurrence in most hospitals with a median 1 case volume of 3 per year. Moreover, only approximately $10\%$ of hospitals perform more than 10 ATAAD repairs 2 , 3 annually. The effect of case volumes has consistently shown that higher-volume centers achieve better patient survival after ATAAD repair compared with lower4 volume centers.

Outcomes for patients with ATAAD might be further improved when patients are managed at centers that 5 , 6 perform a high volume of elective aortic cases. CACs have committed significant resources to develop an advanced and innovative infrastructure as well as multidisciplinary expertise that can offer an array of options to these 7-11 very complicated patients. Efficiency in diagnosis and triage and improved quality metrics are additional 10 , 11 benefits. Therefore, the regionalization of care to CACs has merit, but should be balanced with the need for appropriate access to timely care with optimal patient outcomes ( Table 2 ).

TABLE 2. Interhospital transfer recommendations

|Interhospital Transfer|Interhospital Transfer|Interhospital Transfer|Interhospital Transfer| |---|---|---|---| |1. When cardiac surgery is not immediately available, it is reasonable to transfer patients with ATAAD to a Comprehensive Aortic Center.|IIa|B|3,6,10,12| |2. It may be reasonable to transfer patients with complicated ATAAD to a Comprehensive Aortic Center.|IIb|C|7,10,11|

Focused Clinical Questions

When should patients with ATAAD be transferred to a CAC? When patients with ATAAD present to hospitals without on-site cardiac surgery or when cardiac surgery is not immediately available, interhospital transfer should be considered. Decision-making for transfer is simplified when the next closest hospital is also a CAC. An increasing body of evidence supports the relationship between greater 2 , 3 , 13-15 2 , 16 , 17 hospital and surgeon experience in treating ATAAD and a decline in operative mortality and morbidity. Recent reports from large data sets show operative mortality after repair of ATAAD as between $17\%$ and $20\%$ with individual high-volume aortic centers reporting rates $10\%$ 1 , 18 , 19 consistently below . A study of more than 5000 patients with ATAAD from the National Inpatient Sample database divided annual hospital volume with ATAAD into quartiles: lowest $(^{<3})$ , low $({>}3{-}8)$ , high $({>}8{-}13)$ , and

highest $(\mathord{>}13)$ and showed a significant reduction in operative mortality when low-volume hospitals were compared with high-volume hospitals $(27\%$ vs $16\%$ ; $P<.001)$ ). 2 Dramatic reductions in operative mortality $(33.9\%$ to $2.8\%$ ) were reported when a focused thoracic aortic surgery program not only increased institutional ATAAD volume but also increased total proximal aortic procedure volume, standardized perioperative care, and reduced the number of participating surgeons, thus tripling the experience individ9 ual surgeons obtained in performing these procedures.

Bypassing a low-volume hospital for the benefits of a CAC that might be further away must be balanced with the risk of death during transfer and consequences of delayed treatment. A recent study of 16,886 Medicare benefi- ciaries with ATAAD between 1999 and 2014 showed that $40\%$ of patients were transferred to another hospital. 6 Approximately half of the transferred patients went to a high-volume hospital, defined by the highest decile of open thoracic aortic (elective and emergency) annual volume $(>\!105$ cases) and the other half to a low-volume center that comprised the comparator group. The median additional distance between high- and low-volume hospitals was 50 miles. Despite a delay in transfer because of increased travel distance, surgery at a high-volume hospital conferred a $7.2\%$ $(95\%$ confidence interval, $4.1\%\!-\!10.3\%$ ) absolute risk reduction in operative mortality compared with a low-volume hospital, and this benefit persisted on long-term follow-up. Although death during transfer was unknown, complex sensitivity analysis determined that $4.4\%$ of patients would need to die during the transfer process to negate the benefits of transfer to high-volume hospitals.

When should patients with complicated ATAAD be transferred to a CAC? Regional care models linking rural and community hospitals to high-volume tertiary level facilities with expertise across a spectrum of aortic disease lend further support to the safety of transferring stable patients with ATAAD. A regional system based in Ohio reported their results with 359 patients transferred from 84 7 different hospitals over a 3-year period. Because of a median transfer distance of $66~\mathrm{km}$ , there were no transferrelated mortalities. Another regional system based in Minnesota implemented a multidisciplinary program with 101 patients across 32 hospitals over 7 years in the US Midwest. Despite regionalization of cases, a $43\%$ reduction in the time to ATAAD diagnosis (279 minutes to 160 minutes; $P=.014)$ and a $55\%$ reduction in the time from presenta10 tion to surgical intervention was observed. Moreover, the percentage of patients who received proper anti-impulse therapy also increased dramatically as did the percentage of hospital survivors who participated in long-term follow-up after the index event.

Patients with ATAAD complicated by shock secondary to cardiac tamponade, acute AR, or acute myocardial infarction might be too unstable to tolerate interhospital transfer. However, ATAAD complicated by comorbidities, previous cardiac surgery, or distal malperfusion are candidates for escalation of care to a CAC. Options including aortic root replacement and aortic arch reconstruction are discussed in the following sections, but some surgical and endovascular therapies require an additional level of expertise that might warrant transfer to a CAC.

SECTION 3: SURGICAL TRIAGE

Surgical triage is on the basis of clinical findings and cross-sectional imaging: computed tomographic angiography, magnetic resonance angiography, or transesophageal echocardiography. The imaging must be scrutinized for (1) the diagnosis of AD or IMH, (2) the location of the primary entry tear, (3) the proximal and distal extent of false lumen, and (4) radiologic signs of malperfusion or rupture. Clinical findings are correlated with imaging features to diagnose complications of ATAAD, including pericardial tamponade, AR, malperfusion syndrome, or shock.

Surgery remains the standard of care for ATAAD on the basis of accumulated worldwide data that surgical management significantly outperforms medical management. 1-4 The stark contrast between the $60\%$ 30-day mortality of medical management as reported by Masuda and colleagues 5 and the $26\%$ 30-day mortality of surgical management reported in the same era by Fann and col6 leagues continues to be true today, and emergency surgery is recommended for most patients with ATAAD without delay. However, recent data suggest some notable exceptions, including IMH, catheter-induced ATAAD, retrograde ATAAD, and select cases of malperfusion (discussed in Section 8 ). These circumstances might warrant delayed intervention or expectant management ( Table 3 ).

Focused Clinical Questions

How should IMH be managed? Acute type A IMH can 7 regress spontaneously with medical management alone. However, medical management of IMH is associated with a $37\%$ rate of complications and $29\%$ to $46\%$ risk 7 , 11 of conversion to surgery. Two meta- analyses have shown that overall survival is better with immediate sur7 , 8 gery than expectant management. A few singleinstitution studies have identified risk factors for failure of expectant management that include total aortic diameter ${>}50~\mathrm{mm}$ , hematoma thickness ${\tt>}11\ \mathrm{mm}$ , pericardial 7-9 , 11-13 effusion, AR, and ulcer-like projections. In the absence of these features, it might be reasonable to pursue expectant management of acute type IMH in

5

TABLE 3. Surgical triage recommendations

|Recommendations COR LOEReferences|||| |---|---|---|---| |Surgical Triage|Surgical Triage|Surgical Triage|Surgical Triage| | Emergency surgery is recommended for patients with acute type A aortic dissection. |||1-4| | N Surgery is recommended in patients with type A IMH and one or more high-risk features*. |||7，8| | Expectant management may be reasonable for type A IMH patients with significant comorbidities in the absence of high-risk features*. |||9-13| | Surgery can be effective in patients with ATAAD and brain malperfusion.|ma||14-20| | Nonoperative management is reasonable in catheter induced ATAAD, if limited to the aortic root. |na|E|21-23| | Descending TEVAR alone may be reasonable in selected patients with retrogradeATAAD. |||24,25|

COR , Class of recommendation; $L O E$ , level of evidence; ATAAD , acute type A aortic dissection; IMH , intramural hematoma; TEVAR , thoracic endovascular aortic repair. \*Aortic diameter ${>}50~\mathrm{mm}$ , hematoma thickness ${\tt>}11~\mathrm{mm}$ , pericardial effusion, aortic regurgitation, ulcer-like projection.

patients who have significant comorbidities with close 7-11 , 13 inpatient monitoring and serial imaging.

How should ATAAD with brain malperfusion be managed? The International Registry for Aortic Dissection (IRAD) registry has suggested that the incidence of brain malperfusion in ATAAD is $15\%$ . 26 Patients with ATAAD and brain malperfusion can present with asymp15 , 19 , 27-30 tomatic, radiographic findings to profound coma. The potential for conversion of ischemic to hemorrhagic stroke must be recognized, however, endovascular neurointervention has become the standard of care for acute ischemic stroke in quaternary care centers in 31-34 response to several randomized clinical trials. No such data exist for patients with ATAAD and stroke; however, evidence continues to favor immediate ATAAD surgery, and extrapolation of the acute ischemic stroke 14-18 literature is reasonable. Surgery can reduce acute mortality in selected ATAAD patients with stroke 14-18 , 20 , 35 commensurate to ATAAD without stroke. Moreover, reversal of deficits, including coma, after immediate 19 , 27 , 36 , 37 surgery has been shown in several reports. Nevertheless, ATAAD with brain malperfusion has been associated with a $37\% $ to $50\% $ incidence of persistent 15 , 18 neurological deficit despite proximal aortic repair. A recent study from Michigan suggested the presence of internal carotid occlusion was associated with cerebral edema and herniation in all patients regardless of management 38 strategy. Extent of repair (including carotid artery replacement), as well as initial carotid reperfusion have

39 , 40 been proposed as strategies to improve outcomes. Until more studies become available to inform patient selection and treatment options, proximal aortic repair is reasonable in most patients with brain malperfusion.

How should iatrogenic ATAAD be managed? Limited published data on catheter-induced ATAAD suggests that medical management is reasonable for dissections that are limited to the aortic root in the area immediately surrounding the coronary ostium with careful observation and blood 21-23 pressure control, unless myocardial ischemia occurs.

These localized catheter-induced lesions often heal or stabilize spontaneously after termination of a percutaneous coronary intervention. The success of medical management is largely predicated on very limited tears that are incited in a retrograde fashion, an orientation that might naturally facilitate restored apposition of the torn wall. If a catheterinduced ATAAD extends beyond the aortic root, immediate surgical intervention after confirmation of the diagnosis is warranted.

What is the preferred management of retrograde ATAAD? De novo, retrograde ATAAD occurs when the primary entry tear is distal to the left subclavian artery and the false lumen propagates retrograde into the ascending aorta. Retrograde ATAAD has been successfully treated with endovascular coverage of the primary entry tear in the descending aorta with a covered stent graft in care24 , 25 fully selected patients in a few small series. Anatomy favorable for thoracic endovascular aortic repair (TEVAR) is determined using cross-sectional imaging and includes

an adequate proximal landing zone for the stent graft, often necessitating coverage and revascularization of the left subclavian artery.

Iatrogenic, retrograde ATAAD as a consequence of TEVAR performed for either descending thoracic aortic aneurysm or dissection is often due to injury by the stent graft to 41-43 the intimal surface of the lesser curve of the aortic arch. Poor apposition of the proximal aspect of the stent (bird’s beaking), hereditary thoracic aortic disorder (HTAD), and ascending aortic dilatation ${>}4$ cm might be important risk 41 , 42 , 44-46 factors. Iatrogenic, retrograde ATAAD should be treated by immediate proximal aortic repair unless patient anatomy allows for proximal extension of the TEVAR into the aortic arch.

Can ATAAD after previous coronary artery bypass grafting be delayed for coronary imaging? ATAAD patients with a history of previous coronary artery bypass grafting might benefit from additional preoperative coronary imaging including coronary angiography or computed 47 , 48 tomography (CT) coronary angiography. Previous studies have suggested that pericardial adhesion from previous cardiac surgery might prevent aortic rupture and peri49 cardial tamponade, but recent studies have shown that patients remain at significant risk for all complications of 47 ATAAD. Moreover, the diagnostic CT angiography for ATAAD might also show patency of bypass grafts in patients with previous coronary artery bypass grafting, obviating the need for coronary angiography.

SECTION 4: CANNULATION AND PERFUSION STRATEGY

The complexity of circulatory management and cardiopulmonary bypass (CPB) during ATAAD repair depends

on the extent of aortic reconstruction. Guiding principles for cannulation and perfusion strategy are the establishment of antegrade systemic perfusion whenever possible and the alleviation of malperfusion and end organ ischemia by restoration of true lumen flow ( Table 4 ). Organ protection during periods of aortic cross-clamping and circulatory arrest can be achieved with systemic temperature management, cardioplegia, and brain perfusion strategies.

Blood flow can be affected by the choice of arterial cannulation site for CPB and lead to a dynamic circulation pattern within the lumens of the AD, sometimes requiring adaptation to different sites during the course of the opera1 tion. Cannulation for CPB also has implications on how cerebral perfusion can be provided during circulatory arrest required during arch reconstruction for ATAAD repair. Furthermore, with refinement in brain perfusion and protection strategies, there has been an evolution of the degree of hypothermia when concomitant antegrade cerebral perfusion is used.

Focused Clinical Questions

What is the preferred cannulation site for ATAAD surgery? Right axillary artery cannulation is more commonly performed during ATAAD repair with over $50\%$ usage in Europe and $36\%$ in North America. 18-20 To date, there is no randomized study on the outcomes of the different sites of arterial cannulation. Several retrospective studies have shown decreased risk of stroke and mortality with axillary cannulation compared with other techniques of cannulation. In an analysis of 775 patients, Rosinski and colleagues reported that axillary cannulation was 1 associated with a decreased risk of mortality. In a recent analysis of the STS database of 7353 patients, axillary

TABLE 4. Cannulation and perfusion strategy recommendations

|Recommendations COR LOEReferences|||| |---|---|---|---| |Cannulation and Perfusion Strategy|||| | Right axilary artery cannulation is reasonable for stable patients undergoing ATAADrepair. |ma||1-5| |Ni Direct aortic cannulation with imaging guidance is reasonable for ATAAD repair.|ma|E|6-9| |Femoral artery cannulation may be reasonable for ATAAD repair.|||8，10| | The addition of either ACP or RCP during circulatory arrest is reasonable for ATAAD repair. |ma|B|11-13| | Circulatory arrest with ACP and moderate or deep hypothermia is reasonable for ATAAD repair during extended arch reconstruction. |ma||14-17|

, level of evidence; ATAAD , acute type A aortic dissection; ACP , anterograde cerebral perfusion; RCP , retrograde cerebral perfusion.

COR , Class of recommendation; LOE

2 cannulation was associated with the lowest risk of stroke. In another analysis by Benedetto and colleagues, a metaanalysis of 8 studies including 793 patients, axillary cannulation was associated with a reduced risk of in-hospital mortality and permanent neurologic deficit compared with 3 femoral artery cannulation. However, technical considerations remain and the right axillary artery should be reconsidered if dissected.

Increasing experience has been recently reported with 19 direct ascending aortic cannulation. This technique provides physiologic antegrade perfusion by central cannulation of the ascending aorta. Nonetheless, cannulation of a dissected ascending can be challenging and is performed 21 using the Seldinger technique to access the true lumen. Most importantly, imaging (epiaortic ultrasonography or transesophageal echocardiography) is required to confirm 8 , 9 cannulation of true lumen. In a study of 584 patients, Kreibich and colleagues reported that central aortic cannulation is safe and associated with similar outcomes with regard to stroke and mortality compared with axillary and 8 femoral artery cannulation. In a series of 309 patients, Jormalainen and colleagues reported central aortic cannulation was also associated with a similar outcome of stroke and 7 mortality compared with peripheral cannulation.

Classically, femoral artery cannulation has been widely 18 , 19 used in the past and remains relevant today. The concern regarding femoral artery cannulation is the unpredictable nature of retrograde arterial flow in the dissected aorta resulting in potential worsening of organ malperfu1 , 2 , 6 sion, especially the brain. In an analysis of cannulation strategies in 25,462 patients, Helder and colleagues reported femoral artery cannulation was associated with a significantly greater risk of stroke compared with axillary 6 or central aortic cannulation. In the previously cited STS Adult Cardiac Surgery Database study by Ghoreishi and colleagues, femoral artery cannulation was associated 2 with the highest risk of stroke. However, with the recent increasing trend in axillary and central aortic cannulation in stable patients, there might be an unfavorable selection bias for femoral cannulation. Femoral arterial cannulation remains a rapid and effective technique for arterial cannulation during ATAAD repair, especially in hemodynamically unstable patients.

Should adjunctive brain perfusion be used during circulatory arrest in the ATAAD repair? Over the past 2 decades, brain protection strategy has evolved from the use of isolated deep hypothermic circulatory arrest in initial early experience to currently include retrograde cerebral perfusion (RCP) or antegrade cerebral perfusion (selective unilateral vs bilateral). With regard to comparison of the 2 perfusion strategies in elective arch surgery, there has been no evidence to 22 , 23 suggest superiority of either perfusion strategy. To date, there has been only 1 randomized study to examine outcome differences between anterograde cerebral perfusion (ACP)

and RCP in arch reconstruction during elective surgery, and it showed no difference in stroke, or magnetic resonance imaging (MRI) or neurocognitive studies after total aortic 24 arch replacement. Nonetheless, the trend in Europe and North America has been an increasing use of ACP with vary11 , 18 , 25 ing degrees of hypothermia.

Multiple retrospective analyses have been performed to examine whether the different brain protection strategies have a significant effect on outcomes in ATAAD repair. In the largest series to date, O’Hara and colleagues examined the STS Database in an analysis of 6387 patients who un11 derwent ATAAD repair. Brain perfusion during ATAAD repair with either ACP or RCP was associated with reduced risk of death and stroke compared with hypothermic circulatory arrest without cerebral perfusion.

How should systemic temperature be managed during circulatory arrest during ATAAD repair? When extended arch reconstruction requiring longer duration of circulatory arrest is anticipated, the use of ACP has 5 , 26-29 been advocated by many. With regard to the 30 degree of hypothermia during ATAAD repair, there is evidence to suggest that warmer temperature (moderate hypothermia) is safe and similar to colder temperatures (deep hypothermia) when used with antegrade cerebral 14-17 , 25 , 29 perfusion. There has been no evidence to support that either unilateral or bilateral brain perfusion has superiority in terms of brain protection and out5 , 26 , 29 , 31-33 comes.

SECTION 5: AORTIC ROOT MANAGEMENT

Management of the aortic root in patients with ATAAD is on the basis of the patient’s clinical condition and anatomy defined using cross-sectional imaging. Guiding principles for management of the aortic root are restoration of a well functioning aortic valve, obliteration of the false lumen, and alleviation of coronary malperfusion ( Table 5 ). Detailed examination of the structure and function of the root can direct therapy with assessment of the severity and mechanism of the AR, the extent of the root dissection, and the pattern of coronary artery involvement. Surgical experience should also be considered in the final choice of aortic root preservation or replacement. The need to maximize long-term benefit should be balanced with the primary goal of limiting early operative risk.

Focused Clinical Questions

What is the preferred management of the aortic root and for the aortic valve in the ATAAD? For most patients, a sinus segment-preserving approach to aortic root repair with resuspension of the aortic valve and obliteration of the false lumen within the aortic root is appropriate. AR in patients with ATAAD is often caused by a dissection flap extending below the sinotubular junction, causing detachment and prolapse of one or more of the aortic valve

commissures ( Figure 1 ). All 3 commissures should be resuspended using transmural, pledgeted sutures to reattach the commissures to the aortic wall ( Figure 2 ). The dissection flap often extends into the noncoronary and part of the right coronary sinuses, requiring obliteration of the false lumen within the sinus segment. This may be accomplished by using one or a combination of the following techniques: creation of a neomedia with felt, pericardium, graft, or other material ( Figure 2 ); judicious use of a surgical adhesive; or 15-17 direct suture repair with a fine monofilament suture. Surgical adhesives should be used sparingly to avoid 18 , 19 tissue necrosis and late pseudoaneurysms. Furthermore, neurotoxic effects on the conduction system can 18 , 19 result in heart block. If the aortic sinuses are minimally dissected and not enlarged, but the aortic valve cusps are diseased, then the aortic valve should be replaced along with a supracoronary ascending aortic graft.

Aortic root replacement is recommended in the presence of a root aneurysm or intimal tear within the root. If the tear is in the noncoronary sinus, replacement of a single sinus 20 might be considered. Root replacement is reasonable for patients suspected to have Marfan syndrome or other HTAD. In patients with extensive dissection in all 3 sinuses, aortic root replacement might be unavoidable because of the quality of the tissues. If the aortic valve cusps themselves are calcified or diseased, then the root should be replaced with a composite biological or mechanical valve graft, depending on the patient’s age and other clinical considerations. If the cusps are of good quality, then a valve-sparing aortic root replacement (VSARR) with either a reimplantation or remodeling technique may be considered in experienced centers.

Several retrospective studies have compared the early and late outcomes after root replacement versus limited root repair (valve resuspension with various techniques 1 , 3-9 , 14 of false lumen obliteration) for ATAAD. Root replacement was necessary in approximately $30\%$ to $35\%$ of cases. Indications for root replacement were similar across most studies and included an intimal tear in the root, root diameter ${\tt>}45~\mathrm{mm}$ , HTAD, and unrepairable valve pathology. Although several studies have shown equivalent 1 , 3 , 4 , 14 early and late outcomes of the 2 approaches, others have reported that a root-preserving approach is associated with an increased risk of late AR, root dilatation, and prox2 , 5 , 6 , 8 imal aortic reoperation. Nevertheless, for most patients, valve resuspension with obliteration of the proximal false lumen within the root and a supracoronary graft replacement of the ascending aorta provides satisfactory results. Of note, in the setting of normal cusps and no root aneurysm, valve resuspension and tailoring of the sinotubular junction can treat even severe AR caused by the dissection.

What is the preferred management of the aortic root in patients with ATAAD and HTAD? Root replacement with a composite valve graft might be required in patients with extensive root pathology as described previously. For patients with Marfan syndrome and those with HTAD, aortic root replacement might be particularly beneficial because supracoronary ascending aortic graft replacement is associated with a high $(>\!40\%$ ) need for subsequent rein10 tervention. In single-center series, excellent early and late outcomes have been reported after VSARR with either a reimplantation or remodeling technique in ATAAD pa11 , 13 , 14 tients. In a recent systematic review and metaanalysis outcomes of VSARR with reimplantation of the aortic valve was compared with composite valve graft procedures in patients with ATAAD; improved survival and less aortic valve reintervention were reported after VSARR 12 in carefully selected patients. Because of the additional operative complexity and myocardial ischemia time, however, this approach should be undertaken only by experienced surgeons. Despite a growing body of literature, these reports remain highly selective with relatively small sample sizes, and typically only young and otherwise healthy patients who stand to gain the greatest benefit from valve preservation are offered VSARR in the emergency setting.

TABLE 5. Management of aortic root recommendations

|Recommendations COR LOE References|||| |---|---|---|---| |Aortic Root Management|||| | Aortic valve resuspension is recommended for most patients with ATAAD.||B|¥1—4| | Aortic root replacement is recommended in ATAAD with root aneurysm or primary entry tear in the root. |||③-0| | Aortic root replacement is reasonable in patients with ATAAD and Marfan syndrome or other hereditary thoracic aortic disorders. |ma||¥10| | Valve-sparing aortic root replacement may be reasonable in selected patients withATAAD. |||11-14| | Expeditious coronary artery bypass grafting should be performed in patients with ATAAD and persistent coronary malperfusion after repair. ||C||

COR , Class of recommendation; LOE , level of evidence; ATAAD , acute type A aortic dissection.

 FIGURE 1. Disruption of the aortic root by acute type A dissection. Illustration of potential anatomic consequences of acute type A aortic dissection. A, The dissection flap extends below the sinotubular junction, causing detachment and prolapse of the valve commissure, resulting in aortic regurgitation. B, Malperfusion of the coronary artery from pressurization of the false lumen.

How should bicuspid aortic valve be managed in a setting of ATAAD? Patients with a normally functioning bicuspid aortic valve or with AR caused by the dissection itself and without extensive root pathology might be amenable to valve resuspension and limited root repair techniques. Retrospective series have reported that patients with ATAAD and bicuspid aortic valve present at a younger age and undergo root replacement more often than those with 21-23 tricuspid valves. Early and late results after ATAAD repair are not affected by valve morphology.

What is the preferred management of the ATAAD complicated by persistent coronary malperfusion? ATAAD might lead to coronary malperfusion caused by either static or dynamic obstruction of coronary blood flow ( Figure 1 ). Coronary malperfusion is typically diagnosed by changes in the electrocardiogram, echocardiographic regional wall motion abnormalities, malperfusion on preoperative CT imaging, or intraoperative visualization of a disrupted coronary artery. Malperfusion with myocardial dysfunction is associated with high mortality and must be addressed expeditiously with restoration of

coronary blood flow to all parts of the myocardium. Although the literature is sparse, several techniques have been described, including: obliteration of the false lumen as part of the neomedia repair during valve resuspension; reinforcement of the coronary buttons with pericardium, felt, or other material during root replacement; and direct 24-26 coronary artery repair or bypass grafting. Coronary artery bypass grafting for persistent coronary malperfusion despite successful direct coronary artery repair is necessary before leaving the operating room.

SECTION 6: ASCENDING AORTA AND DISTAL ANASTOMOSIS

The ascending aorta is the most likely segment of aorta to rupture in ATAAD. The surgical objectives during ATAAD repair are resection of the vulnerable aorta including the primary entry tear and restoration of flow into the true lumen. An open distal anastomosis to the proximal arch permits complete resection of the tubular ascending aorta and provides the option of a beveled anastomosis (hemiarch reconstruction) when the primary entry tear extends into the lesser curve of the aortic arch ( Figure 3 ).

Various techniques have been described for preparing the distal anastomosis and includes simple suturing, multilayer reconstruction with felt, pericardial gasket reinforcement, and buttressing with folded redundant adventitia 1-3 ( Figure 3 ). The specific preparation technique for the distal anastomosis is less important than the actual quality of the suture line. During construction of the distal anastomosis, meticulous suturing is important to avoid new intimal tears, minimize operative bleeding complications, 4 and provide late durability. Recommendations for management of the ascending aorta and distal anastomosis are outlined in Table 6 .

 FIGURE 2. Aortic root management. The technique for valve resuspension involves 2 objectives highlighted in the figure. The first is to obliterate the false lumen in the aortic root by construction of neomedia (shown) with Teflon felt or bovine pericardium, use of a surgical adhesive, or simple suture repair. The second is to resuspend the very tips of the commissures with transmural, pledged horizontal mattress sutures without leaving any tubular ascending aorta below the proximal suture line ( inset ).

Focused Clinical Questions

Should the distal aortic anastomosis be performed open or clamped? Because circulatory arrest was first described to facilitate aortic arch surgery, an open distal anastomosis for ATAAD repair has become well accepted for AD involving the arch, but not universally practiced. Advantages of circulatory arrest include optimal exposure of the anastomotic site and complete visualization of the

arch to rule out additional entry tears. An analysis by Lawton and colleagues showed no difference in early outcomes of open and clamped aortic anastomosis, however, they showed that open anastomosis with circulatory arrest was associated with a long-term survival 9 benefit. In a single-center study, Malvindi and colleagues reported no difference in early outcomes of open and clamped anastomosis, but better downstream aortic

11

 FIGURE 3. Ascending aorta and distal anastomosis management. The management of the ascending aorta and distal anastomosis involves 2 objectives shown in the illustration. The first is to completely resect the ascending aorta and primary entry tear, which requires circulatory arrest for an open distal anastomosis. The second is to restore the true lumen flow by reapposition of the dissected aorta during reconstruction of the distal anastomosis. STJ , sinotubular junction; LVOT , left ventricular outflow tract.

10 remodeling in the open anastomosis cohort. In a multicenter analysis of the Nordic Consortium for Acute Type A Aortic Dissection, Geirsson and colleagues reported that ${>}13\%$ of patients underwent repair with the clamped 7 anastomosis. Compared with those who underwent open anastomosis under circulatory arrest, the clamped group had higher mortality and worse survival despite being younger with more bicuspid aortic valves. Although the clamped group had a lower risk of stroke, they also had more coronary disease and shock at presentation, therefore clamp versus open anastomosis was not an independent predictor of outcome. The authors concluded that open anastomosis with circulatory arrest was preferred, but in selected situations, such as patients in cardiogenic shock

at lower-volume hospitals, clamped anastomosis is a reasonable approach.

What extent of resection should be performed in the ATAAD? Several single-center and registry experiences have provided important guidance about basic principles regarding management of the ascending aorta during ATAAD repair, but no randomized clinical studies are available to evaluate the effectiveness of various techniques. Resection of the entire ascending aorta can reduce the risk for proximal aortic reoperation by excising the most vulnerable section of the thoracic aorta 11 and primary entry tear. In a recent analysis of reoperations after ATAAD repair, an aneurysmal aorta beyond the distal anastomosis was associated with a higher risk

TABLE 6. Management of ascending aorta and distal anastomosis recommendations

|Ascending Aorta and Distal Anastomosis Management|Ascending Aorta and Distal Anastomosis Management|Ascending Aorta and Distal Anastomosis Management|Ascending Aorta and Distal Anastomosis Management| |---|---|---|---| |1. Circulatory arrest with open distal anastomosis is preferred in ATAAD.|I|B|5-13|

15 , 16 or reoperation. Moreover, in DeBakey type II ADs where the tear and extent of intimal separation is limited to the ascending aorta, complete resection of the proximal aorta offers the potential for a curative 17 , 18 resection.

In a comparison of ascending only (many with clamped technique) versus hemiarch reconstruction (all under circulatory arrest), Moon and colleagues reported $97\%$ freedom from reoperation for the hemiarch group versus only $76\%$ in the ascending only group at 10 years and no difference in survival. 11 Tamura and colleagues described a $20\%$ incidence of new entry tears at the distal anastomotic site in their series despite the routine use of felt reinforcement 4 and circulatory arrest. The presence of new entry tears was associated with greater distal aortic growth and event rates particularly when it involved the ascending aorta compared with re-entry tears in the descending aorta.

As newer currently investigational endovascular devices designed to treat the arch and ascending aorta have become available, the ascending aortic graft used for ATAAD repair can serve as the proximal landing zone for TEVAR. In such situations, a longer, kink-free landing zone will become increasingly important to optimize seal and fixation and might be best achieved by a complete resection of the ascending aorta.

What is the role of ascending TEVAR in ATAAD? Up to $20\%$ of patients with ATAAD do not undergo surgery. 19 , 20 Although ascending TEVAR might provide a treatment option for inoperable ATAAD patients, no devices are commercially approved; however, results of the early feasi21 bility trials are pending. Initial clinical evidence has shown operative mortality of the procedure using firstgeneration devices to range from $0\%$ to $13\%$ . 22-24 Longterm outcomes are unavailable. Until more evidence is available regarding safety and efficacy, ascending TEVAR for ATAAD should be considered investigational.

SECTION 7: AORTIC ARCH MANAGEMENT

Optimal management of the aortic arch in patients with ATAAD should balance the risk of extended aortic arch replacement with the benefit of additional resection of dissected aorta ( Table 7 ). Most patients with ATAAD can be effectively treated with an open distal anastomosis and complete resection of the ascending aorta and hemiarch as recommended in the previous section. However, some clinical conditions might require an extended arch replacement to address primary entry tears not resectable with hemiarch alone, restore true lumen flow, or resect ruptured distal aorta. Different techniques for extended aortic arch replacement ranges from aortic arch replacement with reconstruction of arch branch vessels, to aortic arch replacement with classical or frozen elephant trunk (FET). Moreover, hybrid arch procedures using surgical and endovascular grafts have been used to address these complex ATAAD. Additional risks of extended aortic arch procedures might result from increased in circulatory arrest times and consequences of prolonged hypothermia, but these risks might be mitigated in experienced 1-4 centers. Multiple factors, such as patient anatomy, presenting features, and comorbidities should be considered when planning extended aortic arch replacement.

TABLE 7. Management of the aortic arch

|Recommendations||COR|LOE|References| |---|---|---|---|---| |Aortic Arch Management||||| || Extended aortic arch replacement is reasonable in patients with ATAAD and: - primary entry tear in the arch or proximal descending thoracic aorta, - brain or peripheral malperfusion, |ma||1-9| |NI| Extended aortic arch replacement with frozen elephant trunk may be reasonable in ATAAD to promote favorable aortic remodeling. |o||| || Extended aortic arch replacement may be considered in young patients with Marfansyndrome or hereditarythoracicaorticdisorders. |||10-23| |||||24-30|

A sequential strategy for patients with ATAAD starts with addressing the life-threatening conditions at the initial operation and ends with the management of the lifelong complications of residual dissection in the distal aorta. Although extended aortic arch replacement has not been shown to reduce the risk of downstream aortic surgery, aortic arch replacement with FET has been shown to promote favorable aortic remodeling and facilitate future completion descending aortic surgery. Moreover, patients with HTAD potentially face a lifetime of aortic operations for replacement of residual, chronically dissected aorta. It is common for these patients to undergo multiple operations, so an extended aortic arch replacement with FET at the initial operation might

reduce the total number of future operations. Performing surgery in a thoughtful sequence might therefore benefit young patients who are at high risk for future aortic complications, but acceptable surgical risk for extended aortic arch surgery at the time of ATAAD repair.

Focused Clinical Questions

When should extended arch surgery be performed in patients with ATAAD? Experience in aortic arch surgery is recommended when considering extended aortic arch replacement in patients with ATAAD. The additional risk of these procedures might be justified for patients with the clinical conditions listed in the recommendation. In $13\%$ to $32\%$ of ATAAD patients, the primary entry tear occurs in the aortic 31-34 arch or proximal descending thoracic aorta, and in many of these cases the primary entry tear cannot be resected with a hemiarch procedure. An extended aortic arch replacement might therefore be reasonable to resect or exclude the primary entry tear, especially when distal malperfusion is 35 present. In IRAD studies, brain malperfusion was reported in $6\%$ to $15\%$ of patients with ATAAD. 36-38 Static occlusion of arch branch vessels might not be relieved by proximal aortic repair alone but might be suitable for arch 39-41 branch reconstruction during aortic arch replacement. Arch aneurysm is present in approximately $6\%$ of ATAAD 42 patients. Furthermore, rupture of the aortic arch might preclude safe hemiarch repair at the time of ATAAD and an extended aortic arch replacement might be required to secure a hemostatic distal anastomosis.

Is it reasonable to use FET in addition to ATAAD surgery? Aortic arch replacement with FET has the immediate benefit of true lumen expansion and coverage of entry tears into the false lumen. Several large series have shown a significant rate of false lumen thrombosis of the treated aorta as high as $85\%$ , ensuring early aortic remodeling. 17 Because the graft used for the aortic arch replacement is continuous with the stent graft of the proximal descending thoracic aorta, migration and type 1a endoleak are avoided in patients who undergo a total arch replacement with FET. Hence, the 21 FET might prevent future operations in the treated segment.

Although FET has the advantage of facilitating either an open or endovascular aortic repair, spinal cord injury (SCI) remains a concern especially when longer stent grafts are used. Several studies have shown that SCI can be avoided by limiting aortic coverage by the FET to at or 11-13 above the sixth intercostal arteries. A convenient echocardiographic and radiographic landmark is the level of the native aortic valve for the sixth thoracic vertebra. A more useful criteria might be the length of the stent graft because most commercial stent grafts are available in 10- or 15-cm lengths. A meta-analysis of more than 3000 patients has shown that 10-cm stent grafts were associated 15 with a significantly lower rate of SCI.

How should the arch be managed in patients with ATAAD and HTAD? Patients with HTAD such as Marfan syndrome are at risk of AD at a young age compared with 43 , 44 the general population. Even after a successful ATAAD repair, the residual dissection in the distal aorta continues to dilate and half of these patients will face further aortic surgery. 26-30 Moreover, in ${>}40\%$ of patients, the entire aorta will require replacement throughout the patient’s lifetime 28 because of aneurysmal degeneration or redissection. Therefore, it might be reasonable to perform an extended aortic arch procedure in young HTAD patients with uncomplicated ATAAD. A strategy of arch replacement with elephant trunk (classical or frozen) followed by an elective thoracoabdominal aortic aneurysm repair might minimize the number and risk of combined aortic interventions for pa24 , 25 tients with HTAD and ATAAD.

SECTION 8: MALPERFUSION MANAGEMENT

Malperfusion is a life-threatening complication of $15\% $ $40\%$ 1-4 ATAAD, with a reported incidence of to . Coronary and brain malperfusion have been discussed in previous sections. Peripheral malperfusion is less common (spinal cord, $2\%–5\%$ ; mesenteric, $4\%–6\%$ ; renal, $6\%–9\%$ ) but can be equally devastating. 2 Defined as ischemia of the vascular bed, malperfusion can lead to malperfusion syndrome characterized by end organ 4 dysfunction. Moreover, end organ dysfunction can exist on a spectrum from systemic inflammation and metabolic derangement to overt organ infarction.

The traditional strategy for treating ATAAD complicated by malperfusion has been immediate proximal aortic repair to restore true lumen flow and resolve branch-vessel occlu3 , 5 sion of the vascular bed ( Figure 4 ). Peripheral revascularization is reserved for ongoing end organ ischemia after successful proximal aortic repair. An alternative strategy in stable patients with ATAAD and malperfusion syndrome reverses the order of interventions in a staged approach and features percutaneous or surgical revascularization as the initial 6-11 intervention before proximal aortic repair ( Table 8 ). Using mesenteric malperfusion as the paradigm, this approach aims to resolve malperfusion syndrome, reduce operative risk of proximal aortic repair, and improve overall survival. However, this strategy might risk aortic rupture because proximal aortic repair is necessarily delayed, and an individualized approach is essential.

Focused Clinical Questions

How should ATAAD patients with malperfusion and end organ dysfunction be managed? Mesenteric malperfusion complicating ATAAD is lethal, and operative mortality after proximal aortic repair ranges from $41\%$ to $100\%$ . 1 An accurate diagnosis of malperfusion syndrome can be a challenge.

 FIGURE 4. Branch vessel obstruction. Aortic dissection can obstruct the branch vessel by either static or dynamic obstruction. In static obstruction ( left panel ) the pressurized false lumen circumferentially narrows the branch vessel to the point of complete obstruction and distal thrombosis. In dynamic obstruction ( right panel ), the pressurized false lumen intermittently displaces the mobile dissection flap over the orifice of the branch vessel. Although dynamic obstruction can be relieved by proximal aortic repair and restoration of true lumen flow, static obstruction may not, because of resulting thrombosis.

Only $60\%$ of patients present with abdominal pain and no laboratory study can completely confirm the presence or absence of mesenteric, end organ dysfunction. ATAAD and mesenteric malperfusion is often associated with liver, renal, and iliofemoral malperfusion due to true lumen compression throughout the abdominal aorta. Multicenter studies have suggested that mortality increases with an increasing number of affected vascular beds. A delay in diagnosis often results in prolonged reduction in blood flow to the splanchnic circulation, irreversible microvascular vasospasm, and transmural intestinal ischemia despite eventual reperfusion.

Historically, the treatment of ATAAD complicated by mesenteric malperfusion has been proximal aortic repair followed by exploratory laparotomy and bowel resection. Despite restoration of true lumen flow after an otherwise successful proximal aortic repair, patients died of metabolic abnormalities and end organ failure. In a report by the

IRAD, mesenteric malperfusion was detected in 68 $(4\%)$ of 1809 patients with ATAAD and mortality in this group $63\%$ 1 was . Improving outcomes for this high-risk cohort requires rapid diagnosis and reversal of ischemia while mini2 mizing the risk of aortic rupture. Because of the poor outcomes associated with traditional strategies, alternative approaches have been described that restore end organ perfusion before proximal aortic 2 , 3 , 6-8 , 10 , 12 , 16 repair. A hybrid strategy allows treatment of mesenteric malperfusion and proximal aortic repair at the 17 same setting. The rationale of proximal aortic repair immediately after mesenteric reperfusion is the avoidance of an interval of expectant management. Operative mortality is reported at $25\%$ to $42\%$ after combined open and en1 , 18 dovascular treatment. This approach requires expertise in open and endovascular surgery, which might involve a team approach. There are no randomized studies on

TABLE 8. Management of malperfusion

|Recommendations COR LOE References|||| |---|---|---|---| |Malperfusion Management|||| | It is reasonable to delay proximal aortic repair until after definitive treatment of mesenteric malperfusion. |||6-11| | NI Descending TEVAR, aortic fenestration, and branch vessel stenting are reasonable treatment options for mesenteric malperfusion. |ma||9，１２| | It may be reasonable to perform revascularization for leg ischemia with sensory/motor deficits before proximal aortic repair. ||C|13-15|

immediate aortic repair compared with initial treatment of mesenteric malperfusion followed by a period of medical stabilization before proximal aortic surgery.

Delay of proximal aortic repair in favor of initial treatment of malperfusion syndrome was first described by Deeb and colleagues; 20 patients were treated with percutaneous aortic fenestration and branch vessel stenting followed by a period 10 of medical stabilization and then proximal aortic repair. Improved outcomes were observed in patients who had malperfusion addressed before aortic repair compared with historical controls, who had immediate aortic repair $(75\%$ survival vs $11\%$ survival). Three patients who had initial treatment for mesenteric malperfusion died before operation including 1 patient who died of aortic rupture on day 12 of medical treatment. The 20-year experience of this strategy was recently updated by Yang and colleagues; mesenteric malperfusion in 82 patients was treated using endovascular 8 reperfusion followed by delayed proximal aortic repair. In-hospital mortality for the entire cohort was $39\%$ . Eleven patients $(13\%)$ died from aortic rupture before open aortic repair; all of these occurred in the first decade of this experience. In patients who recovered from malperfusion after endovascular therapy and went onto open surgical therapy, operative mortality of aortic repair was $2\%$ .

Using lessons learned from experience with TEVAR for complicated acute type B AD, Leshnower and colleagues reported their experience for treatment of mesenteric mal6 perfusion using a TEVAR-first approach. Patients who “ ” had a traditional surgical strategy of initial proximal aortic repair had a $66\%$ mortality compared with a $30\%$ mortality in patients who had a TEVAR-first approach followed by surgical treatment of their dissection. One patient died because of aortic rupture after TEVAR.

How should ATAAD patients with limb ischemia be managed? The mechanisms of limb ischemia in ATAAD are secondary to either static or dynamic obstruction ( Figure 4 ). In the setting of static obstruction (often as a consequence of false lumen thrombosis and true lumen compression in the iliofemoral vessels), proximal aortic repair is unlikely to result in restoration of limb perfusion, 13 , 14 and adjunctive procedures are often necessary. However, dynamic limb malperfusion is associated frequently with associated visceral ischemia. Restoration of limb perfusion after prolonged ischemia can lead to consequences of ischemia reperfusion injury and result in metabolic derangements, renal failure, and loss of limb. Recognizing the association of increasing numbers of vascular beds affected by malperfusion and mortality, restoration of limb perfusion before aortic repair might lead to reduction 1 , 12 , 15 in renal failure, and improvements in early mortality.

POSTOPERATIVE CONSIDERATIONS

Optimal postoperative management for patients recovering from ATAAD consists of blood pressure control and

lifelong radiologic follow-up with cross-sectional imaging of the entire aorta. Several aspects of long-term management should be taken into consideration. First, medical therapy aimed at reducing blood pressure as well as aortic wall stress should be initiated and properly explained to patients to ensure adequate medication adherence. Second, imaging tests should be scheduled at the appropriate time intervals. Diagnostic imaging should be used to assess the aortic valve and ventricular function as well as aortic remodeling. Finally, patients’ first-degree relatives should be screened with transthoracic echocardiography (TTE) and if certain clinical features are present, the patient should be offered genetic testing for an HTAD.

Medical Therapy

Blood pressure management of patients after ATAAD repair has a dramatic effect on long-term outcomes. $\beta\cdot$ -Adrenergic blockade reduces not only heart rate and blood pressure, but also provides anti-impulse therapy to decrease aortic wall 1 stress independent of blood pressure effects. In a recent nationwide study, Chen and colleagues showed beneficial effects of postoperative $\beta$ -blocker use in 396 propensity scorematched pairs of patients. 2 Patients treated with $\beta$ -blockers experienced lower mortality rates $\sqrt[]{16\%}$ vs $27\%$ ; $P<.001]$ ) and strict medical compliance was also associated with improved outcomes. An analysis of the IRAD registry also showed improved survival $(P~=~.006)$ in patients af r ATAAD repair who were subsequently treated with b - 3 blockers. This study showed no association between angiotensin-converting enzyme inhibitor use and mortality. Other studies have also confirmed the importance of $\beta\cdot$ - 4 , 5 blocker usage on outcomes after ATAAD repair.

A growing body of evidence has identified fluoroquinolones, one of the most commonly used group of antibiotics, as causing aortic complications in patients with AD, aneu6-8 rysm, or HTAD. Experimental studies have also confirmed that fluoroquinolones can exacerbate aortic wall damage in the setting of underlying aortic 9 , 10 disease. These findings have been confirmed in population-based studies, leading the US Food and Drug Administration to issue a warning against prescribing systemic fluoroquinolones for patients who have or are at risk of developing an aortic aneurysm because of the increased risk of aortic rupture or dissection.

Postoperative Imaging

Long-term surveillance of patients who underwent successful repair of ATAAD is imperative. Aortic events including rupture and reoperation are a major cause of late morbidity and mortality. Patients with residual distal dissections and particularly those with a patent distal false lumen and proximal tears are at greatest risk for aortic 11 growth and reintervention. Monitoring of the aortic valve and heart function with echocardiography is also critical.

Cross-sectional imaging with either CTor MRI may be used to identify aortic growth and other aortic complications. We suggest that if the renal function permits, predischarge CT or MRI should be performed in addition to scans at 6 months and 1 year. These studies are best performed in multiple phases including noncontrast, arterial phase, and delayed venous phase modes of acquisition to allow for a more complete assessment of false lumen perfusion. Subsequent imaging intervals should be determined according to the condition and size of the residual native aorta, with annual 5 scans being sufficient for most patients.

Genetic Testing and Family Screening

All first-degree relatives of patients who have suffered an ATAAD should be screened with a TTE to rule out the presence of an aortic root or ascending aortic aneurysm. TTE is often sufficient as a diagnostic modality for aortic assessment in family members and should be repeated at 5- to 12-21 10-year intervals if no aortic pathology is identified. Patients with a suspected HTAD including those with syndromic features, a family history of aortic aneurysm or dissection, or young age at diagnosis (younger than 50 years of age or age 50-60 years without hypertension) should be offered genetic assessment and testing. If a pathogenic variant is identified in the patient, then cascade testing of family members should be offered.

CONCLUSIONS AND FUTURE DIRECTIONS

Because of the lethal nature of ATAAD, a condition that is relatively uncommon and not frequently encountered, this writing committee sought to create a set of reasonable evidence-based recommendations aimed at aiding the practicing surgeon in the management of the condition. A well established first principle is the use of antiimpulse therapy before surgical intervention. Second is that expeditious surgery is the preferred approach to ATAAD in almost all instances, including for patients with neurologic deficits. Third, the conduct of the operation should be performed in a manner that is familiar and comfortable for the surgeon. The results of a variety of approaches to arterial cannulation and body temperature management have been reported in nonrandomized studies, with advocates for each; however, the importance of adequate end organ perfusion during repair as a goal is undisputed. The use of circulatory arrest for open distal anastomosis is accepted as is the establishment of antegrade flow after distal repair. Although there is continued controversy over the optimal proximal and distal extent of repair as a means to reduce the risk of late reoperation, there is clear consensus that the highest priority of ATAAD repair is safe conduct of the index operation. Significant root and isolated valve pathology, whether due to the dissection process or underlying aneurysmal disease, should be dealt with in a safe manner either by simple

aortic valve resuspension or root replacement/reconstruction. The extent of distal repair is dictated primarily by the location of the entry tear and the imperative to resect or cover the primary tear. The ultimate role of stent graft techniques including the FET remain uncertain. Malperfusion remains the single greatest challenge in the management of ATAAD, with increasing consideration given to reperfusion of the compromised bed before proximal aortic repair if involving the viscera or limbs. In most other instances, however, proximal aortic repair first is still preferred. Finally, the importance of medical optimization to complement operative intervention cannot be overemphasized. Late postoperative $\beta$ -blockade and imaging surveillance have the potential to greatly affect the disturbingly high late mortality associated with this condition. Similarly, genetic testing and family counseling might identify individuals for prompt prophylactic interventions that prevent this dreaded disease.

Future directions should be targeted at system-level development of timely and rational triage of the patients, improved operative techniques, innovative technology, and stratagems to improve adherence to postoperative management. Finally, prevention and management of ATAAD complications will require detailed databases with long-term outcomes and randomized studies to characterize interventions associated with survival and to inform clinical decision-making.

Conflict of Interest Statement

S.C.M. is a consultant for Terumo Aortic, Cryolife, Edwards, and Medtronic, and has received speaker fees from Terumo Aortic, Cryolife, Edwards, and Medtronic. W.Y.S. is a consultant for Edwards Lifesciences, Medtronic, Terumo Aortic, Aquedeon Medical, and Microinterventional Device, has received speaker fees from Edwards Lifesciences, Medtronic, and Terumo Aortic, and has received research funds from Edwards Lifesciences, Medtronic, Terumo Aortic, WL Gore, Boston Scientific, and Cardiac Dimensions. J.S.C. is a consultant for and has received speaker fees from Terumo Aortic, and has received research funds from Medtronic, Abbott, CytoSorbents, Edwards Lifesciences, and WL Gore. T.G.G. is a consultant for Abbott. M.O. is a consultant for Medtronic. E.E.R. is a consultant for Cryolife, WL Gore, and Medtronic, has received speaker fees from Abbott, Cook, Edwards Lifesciences, LivaNova, and Terumo Aortic, and has received research funding from WL Gore. M.L.S. is a consultant for and has received speaker fees from Terumo Aortic. M.R.M. is a consultant for Medtronic. All other authors reported no conflicts of interest.

The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.

The authors thank Mrs Lori Hrdy Burrows for her assistance and support, Dr Homa Keshavarz for guidance throughout the process, and Mrs Michelle Demetres for providing literature search results.

AATS Clinical Practice Standards Committee members for Adult Cardiac Surgery: Faisal Bakaeen, MD (Co-Chair), S. Christopher Malaisrie, MD (Co-Chair), Joanna Chikwe, MD, Mario F. L. Gaudino, MD, Leonard N. Girardi, MD, and Wilson Y. Szeto, MD.

The invited expert external reviewers are: James I. Fann, MD, T. Brett Reece, MD, John S. Ikonomidis, MD, Antony Estrera, MD, Martin Czerny, MD, Yuichi Ueda, MD, David Pacini, MD, Fernando Fleischman, MD, Ourania A. Preventza, MD, and Loren F. Hiratzka, MD.

References

Background

1. Evangelista A, Isselbacher EM, Bossone E, Gleason TG, Eusanio MD, Sechtem U, et al. Insights from the International Registry of Acute Aortic Dissection: a 20-year experience of collaborative clinical research. Circulation . 2018; 137:1846-60 . 2. Pape LA, Awais M, Woznicki EM, Suzuki T, Trimarchi S, Evangelista A, et al. Presentation, diagnosis, and outcomes of acute aortic dissection: 17-year trends from the International Registry of Acute Aortic Dissection. J Am Coll Cardiol . 2015;66:350-8 . 3. Erbel R, Aboyans V, Boileau C, Bossone E, Bartolomeo RD, Eggebrecht H, et al. 2014 ESC guidelines on the diagnosis and treatment of aortic diseases: document covering acute and chronic aortic diseases of the thoracic and abdominal aorta of the adult. The task force for the diagnosis and treatment of aortic diseases of the European Society of Cardiology (ESC). Eur Heart J . 2014;35:2873-926 . 4. Hiratzka LF, Bakris GL, Beckman JA, Bersin RM, Carr VF, Casey DE Jr, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease: a report of the American College of Cardiology Foundation/American Heart Association task force on practice guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation . 2010;121:e266-369 . 5. Harris KM, Strauss CE, Eagle KA, Hirsh AT, Isselbacher EM, Tsai TT, et al. Correlates of delayed recognition and treatment of acute type aortic dissection. The International Registry of Acute Aortic Dissection (IRAD). Circulation . 2011;124: 1911-8 . 6. Debakey ME, Henly WS, Cooley DA, Morris GC Jr, Crawford ES, Beall AC Jr. Surgical management of dissecting aneurysm involving the ascending aorta. J Cardiovasc Surg (Torino) . 1964;5:200-11 . 7. Debakey ME, Henly WS, Cooley DA, Morris GC Jr, Crawford ES, Beall AC Jr. Surgical management of dissecting aneurysms of the aorta. J Thorac Cardiovasc Surg . 1965;49:130-49 . 8. Hagan PG, Nienaber CA, Isselbacher EM, Bruckman D, Karavite DJ, Russman PL, et al. The International Registry of Acute Aortic Dissection (IRAD): new insights into an old disease. JAMA . 2000;283:897-903 . 9. Hirst AE Jr, Johns VJ Jr, Kime SW Jr. Dissecting aneurysm of the aorta: a review of 505 cases. Medicine (Baltimore) . 1958;37:217-79 . 10. Daily PO, Trueblood HW, Stinson EB, Wuerflein RD, Shumway NE. Management of acute aortic dissections. Ann Thorac Surg . 1970;10:237-47 . 11. Svensson LG, Labib SB, Eisenhauer AC, Butterly JR. Intimal tear without hematoma: an important variant of aortic dissection that can elude current imaging techniques. Circulation . 1999;99:1331-6 . 12. Lombardi JV, Hughes GC, Appoo JJ, Bavaria JE, Beck AW, Cambria RP, et al. Society for Vascular Surgery (SVS) and Society of Thoracic Surgeons (STS) reporting standards for type B aortic dissections. J Vasc Surg . 2020;71:723-47 . 13. Sievers HH, Rylski B, Czerny M, Baier ALM, Kreibich M, Siepe M, et al. Aortic dissection reconsidered: type, entry site, malperfusion classification adding clarity and enabling outcome prediction. Interact Cardiovasc Thorac Surg . 2020;30:451-7 . 14. Czerny M, Pacini D, Aboyans V, Al-Attar N, Eggebrecht H, Evangelista A, et al. Current options and recommendations for the use of thoracic endovascular aortic repair in acute and chronic thoracic aortic disease: an expert consensus document of the European Society for Cardiology (ESC) Working Group of Cardiovascular Surgery, the ESC Working Group on Aorta and Peripheral Vascular Diseases, the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC and the European Association for Cardio-Thoracic Surgery (EACTS). Eur J Cardiothorac Surg . 2021;59:65-73 . 15. VIRTUE Registry Investigators. Mid-term outcomes and aortic remodelling after thoracic endovascular repair for acute, subacute, and chronic aortic dissection: the VIRTUE registry. Eur J Vasc Endovasc Surg . 2014;48:363-71 . 16. JCS Joint Working Group. Guidelines for diagnosis and treatment of aortic aneurysm and aortic dissection (JCS 2011): digest version. Circ J . 2013; 77:789-828 . 17. Appoo JJ, Bozinovski J, Chu MW, El-Hamamsy I, Forbes TL, Ouzounian M, et al. Canadian Cardiovascular Society/Canadian Society of Cardiac Surgeons/ Canadian Society for Vascular Surgery joint position statement on open and endovascular surgery for thoracic aortic disease. Can J Cardiol . 2016;32:703-13 .

Methodology

1. Bakaeen FG, Svensson LG, Mitchell JD, Keshavjee S, Patterson GA, Weisel RD. The American Association for Thoracic Surgery/Society of Thoracic Surgeons position statement on developing clinical practice documents. Ann Thorac Surg . 2017;103:1350-6 . 2. Halperin JL, Levine GN, Al-Khatib SM, Birtcher KK, Bozkurt B, Brindis RG, et al. Further evolution of the ACC/AHA clinical practice guideline recommendation classification system: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. J Am Coll Cardiol . 2016;67:1572-4 . 3. Humphrey-Murto S, Varpio L, Wood TJ, Gonsalves C, Ufholz LA, Mascioli K, et al. The use of the Delphi and other consensus group methods in medical education research: a review. Acad Med . 2017;92:1491-8 . 4. Kwong JS, Chen H, Sun X. Development of evidence-based recommendations: implications for preparing expert consensus statements. Chin Med J (Engl) . 2016;129:2998-3000 .

Section 1: Initial Medical Therapy

1. Chen SW, Lin YS, Wu VC, Lin MS, Chou AH, Chu PH, et al. Effect of betablocker therapy on late outcomes after surgical repair of type A aortic dissection. J Thorac Cardiovasc Surg . 2020;159:1694-1703 e1693 . 2. Krenz JR, O’Brien ME, Lee J, Hayes BD. Evaluation of esmolol for heart rate control in patients with acute aortic dissection. Am J Emerg Med . 2020 . 3. Suzuki T, Isselbacher EM, Nienaber CA, Pyeritz RE, Eagle KA, Tsai TT, et al. Type-selective benefits of medications in treatment of acute aortic dissection (from the International Registry of Acute Aortic Dissection [IRAD]). Am J Cardiol . 2012;109:122-7 . 4. Kim KH, Moon IS, Park JS, Koh YB, Ahn H. Nicardipine hydrochloride injectable phase IV open-label clinical trial: study on the anti-hypertensive effect and safety of nicardipine for acute aortic dissection. J Int Med Res . 2002;30:337-45 . 5. Akutsu K, Yoshino H, Shimokawa T, Ogino H, Kunihara T, Takahashi T, et al. Is systolic blood pressure high in patients with acute aortic dissection on first medical contact before hospital transfer? Heart Vessels . 2019;34:1748-57 . 6. Bossone E, Gorla R, LaBounty TM, Suzuki T, Gilon D, Strauss C, et al. Presenting Systolic Blood Pressure and Outcomes in Patients With Acute Aortic Dissection. J Am Coll Cardiol . 2018;71:1432-40 . 7. Tsai TT, Bossone E, Isselbacher EM, Nienaber CA, Evangelista A, Fang J, et al. Clinical characteristics of hypotension in patients with acute aortic dissection. Am J Cardiol . 2005;95:48-52 . 8. Strayer RJ, Shearer PL, Hermann LK. Screening, evaluation, and early management of acute aortic dissection in the ED. Curr Cardiol Rev . 2012;8:152-7 . 9. Upadhye S, Schiff K. Acute aortic dissection in the emergency department: diagnostic challenges and evidence-based management. Emerg Med Clin North Am . 2012;30:307-327, viii . 10. Ankel F. Aortic dissection. In: Marx JA, Hockberger RS, Walls RM, Adams JG, Barsan WG, Biros MH, et al., eds. Rosen s Emergency Medicine: Concepts and ’ Clinical Practice . Philadelphia: Mosby Elsevier Publishing; 2010:1088-92 . 11. Erbel R, Aboyans V, Boileau C, Bossone E, Bartolomeo RD, Eggebrecht H, et al. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases: Document covering acute and chronic aortic diseases of the thoracic and abdominal aorta of the adult. The Task Force for the Diagnosis and Treatment of Aortic Diseases of the European Society of Cardiology (ESC). Eur Heart J . 2014;35: 2873-926 . 12. Group JCSJW. Guidelines for diagnosis and treatment of aortic aneurysm and aortic dissection (JCS 2011): digest version. Circ J . 2013;77:789-828 . 13. Hiratzka LF, Bakris GL, Beckman JA, Bersin RM, Carr VF, Casey DE Jr, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with Thoracic Aortic Disease: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines, American Association for Thoracic Surgery, American College of Radiology, American Stroke Association, Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, Society of Interventional Radiology, Society of Thoracic Surgeons, and Society for Vascular Medicine. Circulation . 2010;121:e266-369 . 14. Nakai C, Izumi S, Haraguchi T, Kikuta S, Nakayama S, Okita Y, et al. Acute type A aortic dissection with cardiopulmonary arrest at presentation. Ann Thorac Surg . 2020 .

Section 2: Interhospital Transfer

1. Lee TC, Kon Z, Cheema FH, Grau-Sepulveda MV, Englum B, Kim S, et al. Contemporary management and outcomes of acute type A aortic dissection: an analysis of the STS adult cardiac surgery database. J Card Surg . 2018;33:7-18 . 2. Chikwe J, Cavallaro P, Itagaki S, Seigerman M, Diluozzo G, Adams DH. National outcomes in acute aortic dissection: influence of surgeon and institutional volume on operative mortality. Ann Thorac Surg . 2013;95:1563-9 . 3. Merlo AE, Chauhan D, Pettit C, Hong KN, Saunders CR, Chen C, et al. Outcomes following emergent open repair for thoracic aortic dissection are improved at higher volume centers in direct admissions and transfers. J Cardiothorac Surg . 2016;11:118 . 4. Mariscalco G, Maselli D, Zanobini M, Ahmed A, Bruno VD, Benedetto U, et al. Aortic centres should represent the standard of care for acute aortic syndrome. Eur J Prev Cardiol . 2018;25:3-14 . 5. Dobaria V, Kwon OJ, Hadaya J, Sanaiha Y, Sareh S, Aguayo E, et al. Impact of center volume on outcomes of surgical repair for type A acute aortic dissections. Surgery . 2020;168:185-92 . 6. Goldstone AB, Chiu P, Baiocchi M, Lingala B, Lee J, Rigdon J, et al. Interfacility Transfer of Medicare Beneficiaries With Acute Type A Aortic Dissection and Regionalization of Care in the United States. Circulation . 2019;140:1239-50 . 7. Aggarwal B, Raymond CE, Randhawa MS, Roselli E, Jacob J, Eagleton M, et al. Transfer metrics in patients with suspected acute aortic syndrome. Circ Cardiovasc Qual Outcomes . 2014;7:780-2 . 8. Andersen ND, Benrashid E, Ross AK, Pickett LC, Smith PK, Daneshmand MA, et al. The utility of the aortic dissection team: outcomes and insights after a decade of experience. Ann Cardiothorac Surg . 2016;5:194-201 . 9. Andersen ND, Ganapathi AM, Hanna JM, Williams JB, Gaca JG, Hughes GC. Outcomes of acute type a dissection repair before and after implementation of a multidisciplinary thoracic aortic surgery program. J Am Coll Cardiol . 2014;63: 1796-803 . 10. Harris KM, Strauss CE, Duval S, Unger BT, Kroshus TJ, Inampudi S, et al. Multidisciplinary standardized care for acute aortic dissection: design and initial outcomes of a regional care model. Circ Cardiovasc Qual Outcomes . 2010;3:424-30 . 11. Manzur M, Han SM, Dunn J, Elsayed RS, Fleischman F, Casagrande Y, et al. Management of patients with acute aortic syndrome through a regional rapid transport system. J Vasc Surg . 2017;65:21-9 . 12. Izumisawa Y, Endo H, Ichihara N, Takahashi A, Nawata K, Shiraishi H, et al. Association between prehospital transfer distance and surgical mortality in emergency thoracic aortic surgery. J Thorac Cardiovasc Surg . 2020 . 13. Arsalan M, Squiers JJ, Herbert MA, MacHannaford JC, Chamogeorgakis T, Prince SL, et al. Comparison of Outcomes of Operative Therapy for Acute Type A Aortic Dissections Provided at High-Volume Versus Low-Volume Medical Centers in North Texas. Am J Cardiol . 2017;119:323-7 . 14. Brescia AA, Patel HJ, Likosky DS, Watt TMF, Wu X, Strobel RJ, et al. VolumeOutcome Relationships in Surgical and Endovascular Repair of Aortic Dissection. Ann Thorac Surg . 2019;108:1299-306 . 15. Geirsson A, Ahlsson A, Franco-Cereceda A, Fuglsang S, Gunn J, Hansson EC, et al. Hospital volumes and later year of operation correlates with better outcomes in acute Type A aortic dissection. Eur J Cardiothorac Surg . 2018;53: 276-81 . 16. Bashir M, Harky A, Fok M, Shaw M, Hickey GL, Grant SW, et al. Acute type A aortic dissection in the United Kingdom: Surgeon volume-outcome relation. J Thorac Cardiovasc Surg . 2017;154:398-406 e391 . 17. Umana-Pizano JB, Nissen AP, Sandhu HK, Miller CC, Loghin A, SafiHJ, et al. Acute Type A Dissection Repair by High-Volume Vs Low-Volume Surgeons at a High-Volume Aortic Center. Ann Thorac Surg . 2019;108:1330-6 . 18. Easo J, Weigang E, Holzl PP, Horst M, Hoffmann I, Blettner M, et al. Influence of operative strategy for the aortic arch in DeBakey type I aortic dissection: analysis of the German Registry for Acute Aortic Dissection Type A. J Thorac Cardiovasc Surg . 2012;144:617-23 . 19. Pape LA, Awais M, Woznicki EM, Suzuki T, Trimarchi S, Evangelista A, et al. Presentation, Diagnosis, and Outcomes of Acute Aortic Dissection: 17-Year Trends From the International Registry of Acute Aortic Dissection. J Am Coll Cardiol . 2015;66:350-8 .

Section 3: Surgical Triage

1. Evangelista A, Isselbacher EM, Bossone E, Gleason TG, Eusanio MD, Sechtem U, et al. Insights From the International Registry of Acute Aortic Dissection: A 20- Year Experience of Collaborative Clinical Research. Circulation . 2018;137: 1846-60 . 2. Hagan PG, Nienaber CA, Isselbacher EM, Bruckman D, Karavite DJ, Russman PL, et al. The International Registry of Acute Aortic Dissection (IRAD): new insights into an old disease. JAMA . 2000;283:897-903 . 3. Pape LA, Awais M, Woznicki EM, Suzuki T, Trimarchi S, Evangelista A, et al. Presentation, Diagnosis, and Outcomes of Acute Aortic Dissection: 17-Year Trends From the International Registry of Acute Aortic Dissection. J Am Coll Cardiol . 2015;66:350-8 . 4. Weigang E, Conzelmann LO, Kallenbach K, Dapunt O, Karck M. German registry for acute aortic dissection type A (GERAADA)–lessons learned from the registry. Thorac Cardiovasc Surg . 2010;58:154-8 . 5. Masuda Y, Yamada Z, Morooka N, Watanabe S, Inagaki Y. Prognosis of patients with medically treated aortic dissections. Circulation . 1991;84:III7-13 . 6. Fann JI, Smith JA, Miller DC, Mitchell RS, Moore KA, Grunkemeier G, et al. Surgical management of aortic dissection during a 30-year period. Circulation . 1995; 92:II113-121 . 7. Chow SCY, Wong RHL, Lakhani I, Wong MV, Tse G, Yu PSY, et al. Management of acute type A intramural hematoma: upfront surgery or individualized approach? A retrospective analysis and meta-analysis. J Thorac Dis . 2020;12:680-9 . 8. Kan CB, Chang RY, Chang JP. Optimal initial treatment and clinical outcome of type A aortic intramural hematoma: a clinical review. Eur J Cardiothorac Surg . 2008;33:1002-6 . 9. Estrera A, Miller C 3rd, Lee TY, De Rango P, Abdullah S, Walkes JC, et al. Acute type A intramural hematoma: analysis of current management strategy. Circulation . 2009;120:S287-291 . 10. Kitai T, Kaji S, Yamamuro A, Tani T, Tamita K, Kinoshita M, et al. Clinical outcomes of medical therapy and timely operation in initially diagnosed type a aortic intramural hematoma: a 20-year experience. Circulation . 2009;120:S292-298 . 11. Song JK, Yim JH, Ahn JM, Kim DH, Kang JW, Lee TY, et al. Outcomes of patients with acute type a aortic intramural hematoma. Circulation . 2009;120: 2046-52 . 12. Song JM, Kim HS, Song JK, Kang DH, Hong MK, Kim JJ, et al. Usefulness of the initial noninvasive imaging study to predict the adverse outcomes in the medical treatment of acute type A aortic intramural hematoma. Circulation . 2003; 108(Suppl 1):II324-328 . 13. Zhou X, Krishnan A, Hsu J, Burns A, Mandal K. Delayed Surgical Management of Type A Intramural Hematoma Is Not Associated with Worse Outcomes Than Emergent Operation. Heart Surg Forum . 2019;22:E103-6 . 14. Estrera AL, Garami Z, Miller CC, Porat EE, Achouh PE, Dhareshwar J, et al. Acute type A aortic dissection complicated by stroke: can immediate repair be performed safely? J Thorac Cardiovasc Surg . 2006;132:1404-8 . 15. Morimoto N, Okada K, Okita Y. Lack of neurologic improvement after aortic repair for acute type A aortic dissection complicated by cerebral malperfusion: predictors and association with survival. J Thorac Cardiovasc Surg . 2011;142: 1540-4 . 16. Nakamura Y, Tagusari O, Ichikawa Y, Morita A. Impact of immediate aortic repair on early and midterm neurologic status in patients with acute type a aortic dissection complicated by cerebral malperfusion. Ann Thorac Surg . 2011;92:336-8 . 17. Niclauss L, Delay D, Ferrari E, Pretre R. Impact of preoperative central neurologic dysfunction on patients undergoing emergency surgery for type A dissection. Ann Vasc Surg . 2014;28:1227-35 . 18. Tsukube T, Haraguchi T, Okada Y, Matsukawa R, Kozawa S, Ogawa K, et al. Long-term outcomes after immediate aortic repair for acute type A aortic dissection complicated by coma. J Thorac Cardiovasc Surg . 2014;148:1013-8; discussion 1018-1019 .

19

19. Di Eusanio M, Patel HJ, Nienaber CA, Montgomery DM, Korach A, Sundt TM, et al. Patients with type A acute aortic dissection presenting with major brain injury: should we operate on them? J Thorac Cardiovasc Surg . 2013;145: S213-221 e211 . 20. Most H, Reinhard B, Gahl B, Englberger L, Kadner A, Weber A, et al. Is surgery in acute aortic dissection type A still contraindicated in the presence of preoperative neurological symptoms? Eur J Cardiothorac Surg . 2015;48:945-50; discussion 950 . 21. Huenges K, Dreyer J, Panholzer B, Grothusen C, Renner J, Schafer P, et al. Iatrogenic Catheter-Induced Acute Aortic Dissection Type A after Coronary Angiography-A Retrospective Consecutive Case Series. Thorac Cardiovasc Surg . 2017;65:85-9 . 22. N nez-Gil IJ, Bautista D, Cerrato E, Salinas P, Varbella F, Omed e P, et al. Incidence, Management, and Immediate- and Long-Term Outcomes After Iatrogenic Aortic Dissection During Diagnostic or Interventional Coronary Procedures. Circulation . 2015;131:2114-9 . 23. Rylski B, Hoffmann I, Beyersdorf F, Suedkamp M, Siepe M, Nitsch B, et al. Iatrogenic acute aortic dissection type A: insight from the German Registry for Acute Aortic Dissection Type A (GERAADA). Eur J Cardiothorac Surg . 2013;44:353-9; discussion 359 . 24. Omura A, Matsuda H, Matsuo J, Hori Y, Fukuda T, Inoue Y, et al. Thoracic endovascular repair for retrograde acute type A aortic dissection as an alternative choice. Gen Thorac Cardiovasc Surg . 2020 . 25. Shu C, Wang T, Li QM, Li M, Jiang XH, Luo MY, et al. Thoracic endovascular aortic repair for retrograde type A aortic dissection with an entry tear in the descending aorta. J Vasc Interv Radiol . 2012;23:453-60. 460 e451 . 26. Sultan I, Bianco V, Patel HJ, Arnaoutakis GJ, Di Eusanio M, Chen EP, et al. Surgery for type A aortic dissection in patients with cerebral malperfusion: Results from the International Registry of Acute Aortic Dissection. J Thorac Cardiovasc Surg . 2019 . 27. Bossone E, Corteville DC, Harris KM, Suzuki T, Fattori R, Hutchison S, et al. Stroke and outcomes in patients with acute type A aortic dissection. Circulation . 2013;128:S175-9 . 28. Charlton-Ouw KM, Azizzadeh A, Sandhu HK, Sawal A, Leake SS, Miller CC 3rd, et al. Management of common carotid artery dissection due to extension from acute type A (DeBakey I) aortic dissection. J Vasc Surg . 2013; 58:910-6 . 29. Chemtob RA, Fuglsang S, Geirsson A, Ahlsson A, Olsson C, Gunn J, et al. Stroke in acute type A aortic dissection: the Nordic Consortium for Acute Type A Aortic Dissection (NORCAAD). Eur J Cardiothorac Surg . 2020;58:1027-34 . 30. Kreibich M, Rylski B, Czerny M, Beyersdorf F, Itagaki R, Okamura H, et al. Impact of Carotid Artery Involvement in Type A Aortic Dissection. Circulation . 2019;139:1977-8 . 31. Powers WJ, Rabinstein AA, Ackerson T, Adeoye OM, Bambakidis NC, Becker K, et al. 2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke . 2018;49:e46-110 . 32. Campbell BC, Mitchell PJ, Kleinig TJ, Dewey HM, Churilov L, Yassi N, et al. Endovascular therapy for ischemic stroke with perfusion-imaging selection. N Engl J Med . 2015;372:1009-18 . 33. Goyal M, Demchuk AM, Menon BK, Eesa M, Rempel JL, Thornton J, et al. Randomized assessment of rapid endovascular treatment of ischemic stroke. N Engl J Med . 2015;372:1019-30 . 34. Nogueira RG, Jadhav AP, Haussen DC, Bonafe A, Budzik RF, Bhuva P, et al. Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct. N Engl J Med . 2018;378:11-21 . 35. Tsukube T, Hayashi T, Kawahira T, Haraguchi T, Matsukawa R, Kozawa S, et al. Neurological outcomes after immediate aortic repair for acute type A aortic dissection complicated by coma. Circulation . 2011;124:S163-167 . 36. Centofanti P, Flocco R, Ceresa F, Attisani M, La Torre M, Weltert L, et al. Is surgery always mandatory for type A aortic dissection? Ann Thorac Surg . 2006;82: 1658-63; discussion 1664 . 37. Luciani GB. Repair of acute type A aortic dissection in comatose patients. Eur J Cardiothorac Surg . 2015;48:951-2 . 38. Fukuhara S, Norton EL, Chaudhary N, Burris N, Shiomi S, Kim KM, et al. Type A Aortic Dissection with Cerebral Malperfusion: New Insights. Ann Thorac Surg . 2020 . 39. Okita Y, Okada K. Treatment strategies for malperfusion syndrome secondary to acute aortic dissection. J Card Surg . 2020 . 40. Sultan I, Aranda-Michel E, Bianco V, Kilic A, Habertheuer A, Brown JA, et al. Outcomes of carotid artery replacement with total arch reconstruction for type A aortic dissection. Ann Thorac Surg . 2020 . 41. Ma T, Dong ZH, Fu WG, Guo DQ, Xu X, Chen B, et al. Incidence and risk factors for retrograde type A dissection and stent graft-induced new entry after thoracic endovascular aortic repair. J Vasc Surg . 2018;67:1026-1033 e1022 . 42. Yammine H, Briggs CS, Stanley GA, Ballast JK, Anderson WE, Nussbaum T, et al. Retrograde type A dissection after thoracic endovascular aortic repair for type B aortic dissection. J Vasc Surg . 2019;69:24-33 . 43. Zhang S, Chen Y, Lu Q. Retrograde type A aortic dissection complicating endovascular therapy of type B aortic dissection and descending thoracic aneurysm disease. Curr Opin Cardiol . 2018;33:581-6 . 44. Bojko MM, Habertheuer A, Bavaria JE, et al. Recurrent aortic insufficiency after emergency surgery for acute type A aortic dissection with aortic root preservation. The Journal of Thoracic and Cardiovascular Surgery . 2021;161:1989-2000 . 45. Gandet T, Canaud L, Ozdemir BA, Ziza V, Demaria R, Albat B, et al. Factors favoring retrograde aortic dissection after endovascular aortic arch repair. J Thorac Cardiovasc Surg . 2015;150:136-42 . 46. Khoynezhad A, White RA. Pathogenesis and management of retrograde type A aortic dissection after thoracic endovascular aortic repair. Ann Vasc Surg . 2013; 27:1201-6 . 47. Estrera AL, Miller CC, Kaneko T, Lee TY, Walkes JC, Kaiser LR, et al. Outcomes of acute type a aortic dissection after previous cardiac surgery. Ann Thorac Surg . 2010;89:1467-74 . 48. Rylski B, Desai ND, Bavaria JE, Moser W, Vallabhajosyula P, Pochettino A, et al. Type A aortic dissection after previous cardiac surgery: results of an integrated surgical approach. Ann Thorac Surg . 2014;97:1582-8; discussion 1588-1589 . 49. Gillinov AM, Lytle BW, Kaplon RJ, Casselman FP, Blackstone EH, Cosgrove DM. Dissection of the ascending aorta after previous cardiac surgery: differences in presentation and management. J Thorac Cardiovasc Surg . 1999; 117:252-60 .

Section 4: Cannulation and Perfusion Strategy

1. Rosinski BF, Idrees JJ, Roselli EE, Germano E, Pasadyn SR, Lowry AM, et al. Cannulation strategies in acute type A dissection repair: A systematic axillary artery approach. J Thorac Cardiovasc Surg . 2019;158:647-659 e645 . 2. Ghoreishi M, Sundt TM, Cameron DE, Holmes SD, Roselli EE, Pasrija C, et al. Factors associated with acute stroke after type A aortic dissection repair: An analysis of the Society of Thoracic Surgeons National Adult Cardiac Surgery Database. J Thorac Cardiovasc Surg . 2020;159:2143-2154 e2143 . 3. Benedetto U, Mohamed H, Vitulli P, Petrou M. Axillary versus femoral arterial cannulation in type A acute aortic dissection: evidence from a meta-analysis of comparative studies and adjusted risk estimates. Eur J Cardiothorac Surg . 2015; 48:953-9 . 4. Moizumi Y, Motoyoshi N, Sakuma K, Yoshida S. Axillary artery cannulation improves operative results for acute type a aortic dissection. Ann Thorac Surg . 2005; 80:77-83 . 5. Preventza O, Garcia A, Tuluca A, Henry M, Cooley DA, Simpson K, et al. Innominate artery cannulation for proximal aortic surgery: outcomes and neurological events in 263 patients. Eur J Cardiothorac Surg . 2015;48:937-42; discussion 942 . 6. Helder MRK, Schaff HV, Day CN, Pochettino A, Bagameri G, Greason KL, et al. Regional and Temporal Trends in the Outcomes of Repairs for Acute Type A Aortic Dissections. Ann Thorac Surg . 2020;109:26-33 . 7. Jormalainen M, Raivio P, Mustonen C, Honkanen HP, Vento A, Biancari F, et al. Direct Aortic Versus Peripheral Arterial Cannulation in Surgery for Type A Aortic Dissection. Ann Thorac Surg . 2020;110:1251-8 . 8. Kreibich M, Chen Z, Rylski B, Bavaria JE, Brown CR, Branchetti E, et al. Outcome after aortic, axillary, or femoral cannulation for acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019;158:27-34 e29 . 9. Reece TB, Tribble CG, Smith RL, Singh RR, Stiles BM, Peeler BB, et al. Central cannulation is safe in acute aortic dissection repair. J Thorac Cardiovasc Surg . 2007;133:428-34 . 10. MazzeffiM, Ghoreishi M, Alejo D, Fonner CE, Tanaka K, Abernathy JH 3rd, et al. Clinical Practice Variation and Outcomes for Stanford Type A Aortic Dissection Repair Surgery in Maryland: Report from a Statewide Quality Initiative. Aorta (Stamford) . 2020;8:66-73 . 11. O’Hara D, McLarty A, Sun E, Itagaki S, Tannous H, Chu D, et al. Type-A Aortic Dissection and Cerebral Perfusion: The Society of Thoracic Surgeons Database Analysis. Ann Thorac Surg . 2020;110:1461-7 . 12. Sugiura T, Imoto K, Uchida K, Minami T, Yasuda S. Comparative study of brain protection in ascending aorta replacement for acute type A aortic dissection: retrograde cerebral perfusion versus selective antegrade cerebral perfusion. Gen Thorac Cardiovasc Surg . 2012;60:645-8 . 13. Stamou SC, Rausch LA, Kouchoukos NT, Lobdell KW, Khabbaz K, Murphy E, et al. Comparison between antegrade and retrograde cerebral perfusion or profound hypothermia as brain protection strategies during repair of type A aortic dissection. Ann Cardiothorac Surg . 2016;5:328-35 . 14. Comas GM, Leshnower BG, Halkos ME, Thourani VH, Puskas JD, Guyton RA, et al. Acute type a dissection: impact of antegrade cerebral perfusion under moderate hypothermia. Ann Thorac Surg . 2013;96:2135-41 . 15. Keeling WB, Leshnower BG, Hunting JC, Binongo J, Chen EP. Hypothermia and Selective Antegrade Cerebral Perfusion Is Safe for Arch Repair in Type A Dissection. Ann Thorac Surg . 2017;104:767-72 . 16. Leshnower BG, Thourani VH, Halkos ME, Sarin EL, Keeling WB, Lamias MJ, et al. Moderate Versus Deep Hypothermia With Unilateral Selective Antegrade Cerebral Perfusion for Acute Type A Dissection. Ann Thorac Surg . 2015;100: 1563-8; discussion 1568-1569 . 17. Stamou SC, McHugh MA, Conway BD, Nores M. Role of Moderate Hypothermia and Antegrade Cerebral Perfusion during Repair of Type A Aortic Dissection. Int J Angiol . 2018;27:190-5 . 18. De Paulis R, Czerny M, Weltert L, Bavaria J, Borger MA, Carrel TP, et al. Current trends in cannulation and neuroprotection during surgery of the aortic arch in Europe. Eur J Cardiothorac Surg . 2015;47:917-23 . 19. Lee TC, Kon Z, Cheema FH, Grau-Sepulveda MV, Englum B, Kim S, et al. Contemporary management and outcomes of acute type A aortic dissection: An analysis of the STS adult cardiac surgery database. J Card Surg . 2018;33: 7-18 . 20. Sabik JF, Lytle BW, McCarthy PM, Cosgrove DM. Axillary artery: an alternative site of arterial cannulation for patients with extensive aortic and peripheral vascular disease. J Thorac Cardiovasc Surg . 1995;109:885-90; discussion 890- 881 . 21. Shimura S, Odagiri S, Furuya H, Okada K, Ozawa K, Nagase H, et al. Echocardiography-guided aortic cannulation by the Seldinger technique for type A dissection with cerebral malperfusion. J Thorac Cardiovasc Surg . 2020;159: 784-93 . 22. Englum BR, He X, Gulack BC, Ganapathi AM, Mathew JP, Brennan JM, et al. Hypothermia and cerebral protection strategies in aortic arch surgery: a comparative effectiveness analysis from the STS Adult Cardiac Surgery Database. Eur J Cardiothorac Surg . 2017;52:492-8 . 23. Hu Z, Wang Z, Ren Z, Wu H, Zhang M, Zhang H, et al. Similar cerebral protective effectiveness of antegrade and retrograde cerebral perfusion combined with deep hypothermia circulatory arrest in aortic arch surgery: a meta-analysis and systematic review of 5060 patients. J Thorac Cardiovasc Surg . 2014;148:544-60 . 24. Svensson LG, Blackstone EH, Apperson-Hansen C, Ruggieri PM, Ainkaran P, Naugle RI, et al. Implications from neurologic assessment of brain protection for total arch replacement from a randomized trial. J Thorac Cardiovasc Surg . 2015;150:1140-1147 e1111 . 25. Preventza O, Coselli JS. Differential aspects of ascending thoracic aortic dissection and its treatment: the North American experience. Ann Cardiothorac Surg . 2016;5:352-9 . 26. Dong SB, Xiong JX, Zhang K, Zheng J, Xu SD, Liu YM, et al. Different hypothermic and cerebral perfusion strategies in extended arch replacement for acute type a aortic dissection: a retrospective comparative study. J Cardiothorac Surg . 2020;15:236 . 27. Liu Y, Shi Y, Guo H, Yu C, Qian X, Wang W, et al. Aortic balloon occlusion technique versus moderate hypothermic circulatory arrest with antegrade cerebral perfusion in total arch replacement and frozen elephant trunk for acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019 . 28. Yang B, Norton EL, Shih T, Farhat L, Wu X, Hornsby WE, et al. Late outcomes of strategic arch resection in acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019;157:1313-1321 e1312 . 29. Zierer A, El-Sayed Ahmad A, Papadopoulos N, Moritz A, Diegeler A, Urbanski PP. Selective antegrade cerebral perfusion and mild (28 degrees C-30 degrees C) systemic hypothermic circulatory arrest for aortic arch replacement: results from 1002 patients. J Thorac Cardiovasc Surg . 2012;144:1042-9 . 30. Yan TD, Bannon PG, Bavaria J, Coselli JS, Elefteriades JA, Griepp RB, et al. Consensus on hypothermia in aortic arch surgery. Ann Cardiothorac Surg . 2013;2:163-8 . 31. Zierer A, Risteski P, El-Sayed Ahmad A, Moritz A, Diegeler A, Urbanski PP. The impact of unilateral versus bilateral antegrade cerebral perfusion on surgical outcomes after aortic arch replacement: a propensity-matched analysis. J Thorac Cardiovasc Surg . 2014;147:1212-7; discussion 1217-1218 . 32. Norton EL, Wu X, Kim KM, Patel HJ, Deeb GM, Yang B. Unilateral is comparable to bilateral antegrade cerebral perfusion in acute type A aortic dissection repair. J Thorac Cardiovasc Surg . 2020;160:617-625 e615 . 33. Preventza O, Simpson KH, Cooley DA, Cornwell L, Bakaeen FG, Omer S, et al. Unilateral versus bilateral cerebral perfusion for acute type A aortic dissection. Ann Thorac Surg . 2015;99:80-7 .

Section 5: Aortic Root Management

1. Di Eusanio M, Trimarchi S, Peterson MD, Myrmel T, Hughes GC, Korach A, et al. Root replacement surgery versus more conservative management during type A acute aortic dissection repair. Ann Thorac Surg . 2014;98:2078-84 . 2. Chiu P, Trojan J, Tsou S, Goldstone AB, Woo YJ, Fischbein MP. Limited root repair in acute type A aortic dissection is safe but results in increased risk of reoperation. J Thorac Cardiovasc Surg . 2018;155:1-7 e1 . 3. Castrovinci S, Pacini D, Di Marco L, Berretta P, Cefarelli M, Murana G, et al. Surgical management of aortic root in type A acute aortic dissection: a propensityscore analysis. Eur J Cardiothorac Surg . 2016;50:223-9 . 4. Yang B, Norton EL, Hobbs R, Farhat L, Wu X, Hornsby WE, et al. Short- and longterm outcomes of aortic root repair and replacement in patients undergoing acute type A aortic dissection repair: Twenty-year experience. J Thorac Cardiovasc Surg . 2019;157:2125-36 . 5. Bojko MM, Assi R, Bavaria JE, Suhail M, Habertheuer A, Hu RW, et al. Midterm outcomes and durability of sinus segment preservation compared with root replacement for acute type A aortic dissection. J Thorac Cardiovasc Surg . 2020 . 6. Hysi I, Juthier F, Fabre O, Fouquet O, Rousse N, BanfiC, et al. Aortic root surgery improves long-term survival after acute type A aortic dissection. Int J Cardiol . 2015;184:285-90 . 7. Ikeno Y, Yokawa K, Yamanaka K, Inoue T, Tanaka H, Okada K, et al. The fate of aortic root and aortic regurgitation after supracoronary ascending aortic replacement for acute type A aortic dissection. J Thorac Cardiovasc Surg . 2021;161: 483-493 e481 . 8. Nishida H, Tabata M, Fukui T, Takanashi S. Surgical Strategy and Outcome for Aortic Root in Patients Undergoing Repair of Acute Type A Aortic Dissection. Ann Thorac Surg . 2016;101:1464-9 . 9. Chen SK, Qiu ZH, Fang GH, Wu XJ, Chen LW. Reported outcomes after aortic valve resuspension for acute type A aortic dissection: a systematic review and meta-analysis. Interact Cardiovasc Thorac Surg . 2019;29:331-8 . 10. Rylski B, Bavaria JE, Beyersdorf F, Branchetti E, Desai ND, Milewski RK, et al. Type A aortic dissection in Marfan syndrome: extent of initial surgery determines long-term outcome. Circulation . 2014;129:1381-6 . 11. Beckmann E, Martens A, Pertz J, Kaufeld T, Umminger J, Hanke JS, et al. Valvesparing David I procedure in acute aortic type A dissection: a 20-year experience with more than 100 patients. Eur J Cardiothorac Surg . 2017;52:319-24 . 12. Mosbahi S, Stak D, Gravestock I, Burgstaller JM, Steurer J, Eckstein F, et al. A systemic review and meta-analysis: Bentall versus David procedure in acute type A aortic dissection. Eur J Cardiothorac Surg . 2019;55:201-9 . 13. Rosenblum JM, Leshnower BG, Moon RC, Lasanajak Y, Binongo J, McPherson L, et al. Durability and safety of David V valve-sparing root replacement in acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019;157: 14-23 e11 . 14. Sievers HH, Richardt D, Diwoky M, Auer C, Bucsky B, Nasseri B, et al. Survival and reoperation after valve-sparing root replacement and root repair in acute type A dissection. J Thorac Cardiovasc Surg . 2018;156:2076-2082 e2072 . 15. Nakajima T, Kawazoe K, Kataoka T, Kin H, Kazui T, Okabayashi H, et al. Midterm results of aortic repair using a fabric neomedia and fibrin glue for type A acute aortic dissection. Ann Thorac Surg . 2007;83:1615-20 . 16. Rylski B, Bavaria JE, Milewski RK, Vallabhajosyula P, Moser W, Kremens E, et al. Long-term results of neomedia sinus valsalva repair in 489 patients with type A aortic dissection. Ann Thorac Surg . 2014;98:582-8; discussion 588-589 . 17. Yang B. Reply From the authors: Can we just trust our suture lines! J Thorac Cardiovasc Surg . 2020;159:e105-6 . 18. Lemaire SA, Ochoa LN, Conklin LD, Schmittling ZC, Undar A, Clubb FJ Jr, et al. Nerve and conduction tissue injury caused by contact with BioGlue. J Surg Res . 2007;143:286-93 . 19. LeMaire SA, Schmittling ZC, Coselli JS, Undar A, Deady BA, Clubb FJ Jr, et al. BioGlue surgical adhesive impairs aortic growth and causes anastomotic strictures. Ann Thorac Surg . 2002;73:1500-5; discussion 1506 . 20. Svensson LG. Limited Intimal Aorta Tears: Royalty Torn Asunder, and a Nation Was Created. J Am Coll Cardiol . 2018;71:2786-9 .

21

21. Kreibich M, Rylski B, Czerny M, Pingpoh C, Siepe M, Beyersdorf F, et al. Type A Aortic Dissection in Patients With Bicuspid Aortic Valve Aortopathy. Ann Thorac Surg . 2020;109:94-100 . 22. Mennander A, Olsson C, Jeppsson A, Geirsson A, Hjortdal V, Hansson EC, et al. The significance of bicuspid aortic valve after surgery for acute type A aortic dissection. J Thorac Cardiovasc Surg . 2020;159:760-767 e763 . 23. Rylski B, Desai ND, Bavaria JE, Vallabhajosyula P, Moser W, Pochettino A, et al. Aortic valve morphology determines the presentation and surgical approach to acute type A aortic dissection. Ann Thorac Surg . 2014;97:1991-6; discussion 1996-1997 . 24. Chen YF, Chien TM, Yu CP, Ho KJ, Wen H, Li WY, et al. Acute aortic dissection type A with acute coronary involvement: a novel classification. Int J Cardiol . 2013;168:4063-9 . 25. Kreibich M, Bavaria JE, Branchetti E, Brown CR, Chen Z, Khurshan F, et al. Management of Patients With Coronary Artery Malperfusion Secondary to Type A Aortic Dissection. Ann Thorac Surg . 2019;107:1174-80 . 26. Neri E, Toscano T, Papalia U, Frati G, Massetti M, Capannini G, et al. Proximal aortic dissection with coronary malperfusion: presentation, management, and outcome. J Thorac Cardiovasc Surg . 2001;121:552-60 .

Section 6: Ascending Aorta and Distal Anastomosis

1. Fleck TM, Tschernich H, Grabenwoger M, Hutschala D, Koinig H, Wolner E, et al. A double patch sandwich technique for surgical repair of acute aortic dissection type A. Ann Thorac Surg . 2003;76:499-502 . 2. Oda T, Minatoya K, Sasaki H, Tanaka H, Seike Y, Itonaga T, et al. Adventitial inversion technique for type A aortic dissection distal anastomosis. J Thorac Cardiovasc Surg . 2016;151:1340-5 . 3. Szeto WY, Gleason TG. Operative management of ascending aortic dissections. Semin Thorac Cardiovasc Surg . 2005;17:247-55 . 4. Tamura K, Chikazawa G, Hiraoka A, Totsugawa T, Sakaguchi T, Yoshitaka H. The prognostic impact of distal anastomotic new entry after acute type I aortic dissection repair. Eur J Cardiothorac Surg . 2017;52:867-73 . 5. Danner BC, Natour E, Horst M, Dikov V, Ghosh PK, Dapunt OE. Comparison of operative techniques in acute type A aortic dissection performing the distal anastomosis. J Card Surg . 2007;22:105-10 . 6. David TE, Armstrong S, Ivanov J, Barnard S. Surgery for acute type A aortic dissection. Ann Thorac Surg . 1999;67:1999-2001; discussion 2014-1999 . 7. Geirsson A, Shioda K, Olsson C, Ahlsson A, Gunn J, Hansson EC, et al. Differential outcomes of open and clamp-on distal anastomosis techniques in acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019;157:1750-8 . 8. Lai DT, Robbins RC, Mitchell RS, Moore KA, Oyer PE, Shumway NE, et al. Does profound hypothermic circulatory arrest improve survival in patients with acute type a aortic dissection? Circulation . 2002;106:I218-228 . 9. Lawton JS, Liu J, Kulshrestha K, Moon MR, Damiano RJ Jr, Maniar H, et al. The impact of surgical strategy on survival after repair of type A aortic dissection. J Thorac Cardiovasc Surg . 2015;150:294-301 e291 . 10. Malvindi PG, Modi A, Miskolczi S, Kaarne M, Velissaris T, Barlow C, et al. Open and closed distal anastomosis for acute type A aortic dissection repair. Interact Cardiovasc Thorac Surg . 2016;22:776-83 . 11. Moon MR, Sundt TM 3rd, Pasque MK, Barner HB, Huddleston CB, Damiano RJ Jr, et al. Does the extent of proximal or distal resection influence outcome for type A dissections? Ann Thorac Surg . 2001;71:1244-9; discussion 1249-1250 . 12. Stamou SC, Kouchoukos NT, Hagberg RC, Khabbaz KR, Robicsek F, Nussbaum M, et al. Does the technique of distal anastomosis influence clinical outcomes in acute type A aortic dissection? Interact Cardiovasc Thorac Surg . 2011;12:404-8 . 13. Zierer A, Moon MR, Melby SJ, Moazami N, Lawton JS, Kouchoukos NT, et al. Impact of perfusion strategy on neurologic recovery in acute type A aortic dissection. Ann Thorac Surg . 2007;83:2122-8; discussion 2128-2129 . 14. Bavaria JE, Pochettino A, Brinster DR, Gorman RC, McGarvey ML, Gorman JH, et al. New paradigms and improved results for the surgical treatment of acute type A dissection. Ann Surg . 2001;234:336-42; discussion 342-333 . 15. Roselli EE, Loor G, He J, Rafael AE, Rajeswaran J, Houghtaling PL, et al. Distal aortic interventions after repair of ascending dissection: the argument for a more aggressive approach. J Thorac Cardiovasc Surg . 2015;149:S117-124 e113 . 16. Preventza O, Price MD, Simpson KH, Cooley DA, Pocock E, de la Cruz KI, et al. Hemiarch and Total Arch Surgery in Patients With Previous Repair of Acute Type I Aortic Dissection. Ann Thorac Surg . 2015;100:833-8 . 17. Dohle DS, El Beyrouti H, Brendel L, Pfeiffer P, El-Mehsen M, Vahl CF. Survival and reinterventions after isolated proximal aortic repair in acute type A aortic dissection. Interact Cardiovasc Thorac Surg . 2019;28:981-8 . 18. Kohl LP, Isselbacher EM, Majahalme N, Evangelista A, Russo MJ, Hutchison S, et al. Comparison of Outcomes in DeBakey Type AI Versus AII Aortic Dissection. Am J Cardiol . 2018;122:689-95 . 19. Evangelista A, Isselbacher EM, Bossone E, Gleason TG, Eusanio MD, Sechtem U, et al. Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research. Circulation . 2018;137:1846-60 . 20. Wang DJ, Fan FD, Wang Q, Li QG, Zhou Q, Wu Z, et al. Preliminary characterization of acute aortic dissection in the mainland of China. Chin Med J (Engl). . 2011;124:1726-30 . 21. Muetterties CE, Menon R, Wheatley GH 3rd. A systematic review of primary endovascular repair of the ascending aorta. J Vasc Surg . 2018;67:332-42 . 22. Preventza O, Olive JK, Liao JL, Orozco-Sevilla V, Simpson K, Rodriguez MR, et al. Acute type I aortic dissection with or without antegrade stent delivery: Mid-term outcomes. J Thorac Cardiovasc Surg . 2019;158:1273-81 . 23. Vallabhajosyula P, Gottret JP, Bavaria JE, Desai ND, Szeto WY. Endovascular repair of the ascending aorta in patients at high risk for open repair. J Thorac Cardiovasc Surg . 2015;149:S144-150 . 24. Roselli EE, Idrees JJ, Johnston DR, Eagleton MJ, Desai MY, Svensson LG. Zone zero thoracic endovascular aortic repair: A proposed modification to the classifi- cation of landing zones. J Thorac Cardiovasc Surg . 2018;155:1381-9 .

Section 7: Aortic Arch Management

1. Easo J, Weigang E, Holzl PP, Horst M, Hoffmann I, Blettner M, et al. Influence of operative strategy for the aortic arch in DeBakey type I aortic dissection: analysis of the German Registry for Acute Aortic Dissection Type A. J Thorac Cardiovasc Surg . 2012;144:617-23 . 2. Poon SS, Theologou T, Harrington D, Kuduvalli M, Oo A, Field M. Hemiarch versus total aortic arch replacement in acute type A dissection: a systematic review and meta-analysis. Ann Cardiothorac Surg . 2016;5:156-73 . 3. Salem M, Friedrich C, Rusch R, Frank D, Hoffmann G, Lutter G, et al. Is total arch replacement associated with an increased risk after acute type A dissection? J Thorac Dis . 2020;12:5517-31 . 4. Yang B, Norton EL, Shih T, Farhat L, Wu X, Hornsby WE, et al. Late outcomes of strategic arch resection in acute type A aortic dissection. J Thorac Cardiovasc Surg . 2019;157:1313-1321 e1312 . 5. Kazui T, Yamashita K, Washiyama N, Terada H, Bashar AH, Suzuki T, et al. Impact of an aggressive surgical approach on surgical outcome in type A aortic dissection. Ann Thorac Surg . 2002;74:S1844-1847; discussion S1857- 1863 . 6. Ohtsubo S, Itoh T, Takarabe K, Rikitake K, Furukawa K, Suda H, et al. Surgical results of hemiarch replacement for acute type A dissection. Ann Thorac Surg . 2002;74:S1853-1856; discussion S1857-1863 . 7. Smith HN, Boodhwani M, Ouzounian M, Saczkowski R, Gregory AJ, Herget EJ, et al. Classification and outcomes of extended arch repair for acute Type A aortic dissection: a systematic review and meta-analysis. Interact Cardiovasc Thorac Surg . 2017;24:450-9 . 8. Trimarchi S, Nienaber CA, Rampoldi V, Myrmel T, Suzuki T, Mehta RH, et al. Contemporary results of surgery in acute type A aortic dissection: The International Registry of Acute Aortic Dissection experience. J Thorac Cardiovasc Surg . 2005;129:112-22 . 9. Sultan I, Aranda-Michel E, Bianco V, Kilic A, Habertheuer A, Brown JA, et al. Outcomes of carotid artery replacement with total arch reconstruction for type A aortic dissection. Ann Thorac Surg . 2020 . 10. Detter C, Demal TJ, Bax L, Tsilimparis N, Kolbel T, von Kodolitsch Y, et al. Simplified frozen elephant trunk technique for combined open and endovascular treatment of extensive aortic diseases. Eur J Cardiothorac Surg . 2019;56:738-45 . 11. Flores J, Kunihara T, Shiiya N, Yoshimoto K, Matsuzaki K, Yasuda K. Extensive deployment of the stented elephant trunk is associated with an increased risk of spinal cord injury. J Thorac Cardiovasc Surg . 2006;131:336-42 . 12. Katayama K, Uchida N, Katayama A, Takahashi S, Takasaki T, Kurosaki T, et al. Multiple factors predict the risk of spinal cord injury after the frozen elephant trunk technique for extended thoracic aortic disease. Eur J Cardiothorac Surg . 2015;47:616-20 . 13. Okita Y. Frozen elephant trunk with Frozenix prosthesis. Ann Cardiothorac Surg . 2020;9:152-63 . 14. Okita Y, Kumamaru H, Motomura N, Miyata H, Takamoto S. Current status of open surgery for acute type A aortic dissection in Japan. J Thorac Cardiovasc Surg . 2020 . 15. Preventza O, Liao JL, Olive JK, Simpson K, Critsinelis AC, Price MD, et al. Neurologic complications after the frozen elephant trunk procedure: A metaanalysis of more than 3000 patients. J Thorac Cardiovasc Surg . 2020;160: 20-33 e24 . 16. Roselli EE, Idrees JJ, Bakaeen FG, Tong MZ, Soltesz EG, Mick S, et al. Evolution of Simplified Frozen Elephant Trunk Repair for Acute DeBakey Type I Dissection: Midterm Outcomes. Ann Thorac Surg . 2018;105:749-55 . 17. Shrestha M, Bachet J, Bavaria J, Carrel TP, De Paulis R, Di Bartolomeo R, et al. Current status and recommendations for use of the frozen elephant trunk technique: a position paper by the Vascular Domain of EACTS. Eur J Cardiothorac Surg . 2015;47:759-69 . 18. Shrestha M, Beckmann E, Krueger H, Fleissner F, Kaufeld T, Koigeldiyev N, et al. The elephant trunk is freezing: The Hannover experience. J Thorac Cardiovasc Surg . 2015;149:1286-93 . 19. Svensson LG, Rushing GD, Valenzuela ES, Rafael AE, Batizy LH, Blackstone EH, et al. Modifications, classification, and outcomes of elephanttrunk procedures. Ann Thorac Surg . 2013;96:548-58 . 20. Takagi H, Umemoto T, Group A. A Meta-Analysis of Total Arch Replacement With Frozen Elephant Trunk in Acute Type A Aortic Dissection. Vasc Endovascular Surg . 2016;50:33-46 . 21. Tsagakis K, Dohle D, Benedik J, Lieder H, Jakob H. Overall Essen’s experience with the E-vita open hybrid stent graft system and evolution of the surgical technique. Ann Cardiothorac Surg . 2013;2:612-20 . 22. Beckmann E, Martens A, Korte W, Kaufeld T, Krueger H, Haverich A, et al. Open total arch replacement with trifurcated graft and frozen elephant trunk. Ann Cardiothorac Surg . 2020;9:170-7 . 23. Shrestha M, Kaufeld T, Beckmann E, Fleissner F, Umminger J, Abd Alhadi F, et al. Total aortic arch replacement with a novel 4-branched frozen elephant trunk prosthesis: Single-center results of the first 100 patients. J Thorac Cardiovasc Surg . 2016;152:148-159 e141 . 24. Chen Y, Ma WG, Zheng J, Liu YM, Zhu JM, Sun LZ. Total arch replacement and frozen elephant trunk for type A aortic dissection after Bentall procedure in Marfan syndrome. J Thorac Dis . 2018;10:2377-87 . 25. Chen Y, Ma WG, Zhi AH, Lu L, Zheng J, Zhang W, et al. Fate of distal aorta after frozen elephant trunk and total arch replacement for type A aortic dissection in Marfan syndrome. J Thorac Cardiovasc Surg . 2019;157:835-49 . 26. Girdauskas E, Kuntze T, Borger MA, Falk V, Mohr FW. Distal aortic reinterventions after root surgery in Marfan patients. Ann Thorac Surg . 2008;86:1815-9 . 27. Mimoun L, Detaint D, Hamroun D, Arnoult F, Delorme G, Gautier M, et al. Dissection in Marfan syndrome: the importance of the descending aorta. Eur Heart J . 2011;32:443-9 . 28. Rylski B, Bavaria JE, Beyersdorf F, Branchetti E, Desai ND, Milewski RK, et al. Type A aortic dissection in Marfan syndrome: extent of initial surgery determines long-term outcome. Circulation . 2014;129:1381-6 . 29. Schoenhoff FS, Jungi S, Czerny M, Roost E, Reineke D, Matyas G, et al. Acute aortic dissection determines the fate of initially untreated aortic segments in Marfan syndrome. Circulation . 2013;127:1569-75 . 30. Roselli EE, Idrees JJ, Lowry AM, Masabni K, Soltesz EG, Johnston DR, et al. Beyond the Aortic Root: Staged Open and Endovascular Repair of Arch and Descending Aorta in Patients With Connective Tissue Disorders. Ann Thorac Surg . 2016;101:906-12 . 31. Inoue Y, Minatoya K, Oda T, Itonaga T, Seike Y, Tanaka H, et al. Surgical outcomes for acute type A aortic dissection with aggressive primary entry resection. Eur J Cardiothorac Surg . 2016;50:567-73 . 32. Ma WG, Zhang W, Wang LF, Zheng J, Ziganshin BA, Charilaou P, et al. Type A aortic dissection with arch entry tear: Surgical experience in 104 patients over a 12-year period. J Thorac Cardiovasc Surg . 2016;151:1581-92 . 33. Song SB, Wu XJ, Sun Y, Cai SH, Hu PY, Qiang HF. A modified frozen elephant trunk technique for acute Stanford type A aortic dissection. J Cardiothorac Surg . 2020;15:322 . 34. Trimarchi S, de Beaufort HWL, Tolenaar JL, Bavaria JE, Desai ND, Di Eusanio M, et al. Acute aortic dissections with entry tear in the arch: A report from the International Registry of Acute Aortic Dissection. J Thorac Cardiovasc Surg . 2019;157:66-73 . 35. Shrestha M, Martens A, Kaufeld T, Beckmann E, Bertele S, Krueger H, et al. Single-centre experience with the frozen elephant trunk technique in 251 patients over 15 years. Eur J Cardiothorac Surg . 2017;52:858-66 . 36. Bossone E, Corteville DC, Harris KM, Suzuki T, Fattori R, Hutchison S, et al. Stroke and outcomes in patients with acute type A aortic dissection. Circulation . 2013;128:S175-179 . 37. Di Eusanio M, Patel HJ, Nienaber CA, Montgomery DM, Korach A, Sundt TM, et al. Patients with type A acute aortic dissection presenting with major brain injury: should we operate on them? J Thorac Cardiovasc Surg . 2013;145: S213-221 e211 . 38. Sultan I, Bianco V, Patel HJ, Arnaoutakis GJ, Di Eusanio M, Chen EP, et al. Surgery for type A aortic dissection in patients with cerebral malperfusion: Results from the International Registry of Acute Aortic Dissection. J Thorac Cardiovasc Surg . 2019 . 39. Dai XF, Chen LW, Wu XJ, Dong Y, Wang QM. Total Aortic Arch Reconstruction With Triple-Branched Stent Graft or Hemiarch Replacement for Acute Debakey Type I Aortic Dissection: Five-Years Experience With 93 Patients. J Card Surg . 2015;30:749-55 . 40. Lu S, Yang S, Lai H, Zheng J, Hong T, Sun X, et al. Open aortic arch reconstruction for acute type a aortic dissection: a single-center experience with 267 consecutive patients. J Cardiothorac Surg . 2016;11:111 . 41. Zhang Q, Ma X, Zhang W, Wang Z, Zhang H, Zhang X, et al. Surgical repair and reconstruction of aortic arch in debakey type I aortic dissection: recent advances and single-center experience in the application of branched stent graft. J Cardiothorac Surg . 2017;12:86 . 42. Evangelista A, Isselbacher EM, Bossone E, Gleason TG, Eusanio MD, Sechtem U, et al. Insights From the International Registry of Acute Aortic Dissection: A 20-Year Experience of Collaborative Clinical Research. Circulation . 2018;137:1846-60 . 43. Murdoch JL, Walker BA, Halpern BL, Kuzma JW, McKusick VA. Life expectancy and causes of death in the Marfan syndrome. N Engl J Med . 1972;286: 804-8 . 44. Vanem TT, Geiran OR, Krohg-Sorensen K, Roe C, Paus B, Rand-Hendriksen S. Survival, causes of death, and cardiovascular events in patients with Marfan syndrome. Mol Genet Genomic Med . 2018;6:1114-23 .

Section 8: Malperfusion Management

1. Di Eusanio M, Trimarchi S, Patel HJ, Hutchison S, Suzuki T, Peterson MD, et al. Clinical presentation, management, and short-term outcome of patients with type A acute dissection complicated by mesenteric malperfusion: observations from the International Registry of Acute Aortic Dissection. J Thorac Cardiovasc Surg . 2013;145:385-390 e381 . 2. Iannacone E, Robinson B, Rahouma M, Girardi L. Management of malperfusion: New York approach and outcomes. J Card Surg . 2020 . 3. Geirsson A, Szeto WY, Pochettino A, McGarvey ML, Keane MG, Woo YJ, et al. Significance of malperfusion syndromes prior to contemporary surgical repair for acute type A dissection: outcomes and need for additional revascularizations. Eur J Cardiothorac Surg . 2007;32:255-62 . 4. Grimm JC, Magruder JT, Crawford TC, Sciortino CM, Zehr KJ, Mandal K, et al. Differential outcomes of type A dissection with malperfusion according to affected organ system. Ann Cardiothorac Surg . 2016;5:202-8 . 5. Girardi LN, Krieger KH, Lee LY, Mack CA, Tortolani AJ, Isom OW. Management strategies for type A dissection complicated by peripheral vascular malperfusion. Ann Thorac Surg . 2004;77:1309-14; discussion 1314 . 6. Leshnower BG, Keeling WB, Duwayri YM, Jordan WD Jr, Chen EP. The "thoracic endovascular aortic repair-first" strategy for acute type A dissection with mesenteric malperfusion: Initial results compared with conventional algorithms. J Thorac Cardiovasc Surg . 2019;158:1516-24 . 7. Uchida K, Karube N, Kasama K, Minami T, Yasuda S, Goda M, et al. Early reperfusion strategy improves the outcomes of surgery for type A acute aortic dissection with malperfusion. J Thorac Cardiovasc Surg . 2018;156:483-9 . 8. Yang B, Norton EL, Rosati CM, Wu X, Kim KM, Khaja MS, et al. Managing patients with acute type A aortic dissection and mesenteric malperfusion syndrome: A 20-year experience. J Thorac Cardiovasc Surg . 2019;158:675-687 e674 . 9. Yang B, Rosati CM, Norton EL, Kim KM, Khaja MS, Dasika N, et al. Endovascular Fenestration/Stenting First Followed by Delayed Open Aortic Repair for Acute Type A Aortic Dissection With Malperfusion Syndrome. Circulation . 2018;138:2091-103 . 10. Deeb GM, Williams DM, Bolling SF, Quint LE, Monaghan H, Sievers J, et al. Surgical delay for acute type A dissection with malperfusion. Ann Thorac Surg . 1997;64:1669-75; discussion 1675-1667 .

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ARTICLE IN PRESS

11. Sugiyama K, Watanuki H, Okada M, Futamura Y, Wakayama R, Matsuyama K. Revascularization-first strategy in acute aortic dissection with mesenteric malperfusion. J Card Surg . 2020;35:3004-9 . 12. Leshnower BG, Veeraswamy RK, Duwayri YM, Chen EP. The "TEVAR-first" approach to DeBakey I aortic dissection with mesenteric malperfusion. Ann Thorac Surg . 2014;97:693-6 . 13. Charlton-Ouw KM, Sandhu HK, Leake SS, Jeffress K, Miller CCR, Durham CA, et al. Need for Limb Revascularization in Patients with Acute Aortic Dissection is Associated with Mesenteric Ischemia. Ann Vasc Surg . 2016;36:112-20 . 14. Charlton-Ouw KM, Sritharan K, Leake SS, Sandhu HK, Miller CC 3rd, Azizzadeh A, et al. Management of limb ischemia in acute proximal aortic dissection. J Vasc Surg . 2013;57:1023-9 . 15. Long SM 3rd, Nair D, Halandras PM, Kasirajan K, Milner R, Chen EP. Ileofemoral malperfusion complicating type a dissection: revascularization prevents renal failure. Ann Thorac Surg . 2007;84:2099-101 . 16. Kawahito K, Kimura N, Yamaguchi A, Aizawa K. Malperfusion in type A aortic dissection: results of emergency central aortic repair. Gen Thorac Cardiovasc Surg . 2019;67:594-601 . 17. Perera NK, Galvin SD, Seevanayagam S, Matalanis G. Optimal management of acute type A aortic dissection with mesenteric malperfusion. Interact Cardiovasc Thorac Surg . 2014;19:290-4 . 18. Tsagakis K, Konorza T, Dohle DS, Kottenberg E, Buck T, Thielmann M, et al. Hybrid operating room concept for combined diagnostics, intervention and surgery in acute type A dissection. Eur J Cardiothorac Surg . 2013;43: 397-404 .

Postoperative Considerations

1. Svensson LG, Crawford ES. Aortic dissection and aortic aneurysm surgery: clinical observations, experimental investigations, and statistical analyses. Part I. Curr Probl Surg . 1992;29:817-911 . 2. Chen SW, Lin YS, Wu VC, Lin MS, Chou AH, Chu PH, et al. Effect of betablocker therapy on late outcomes after surgical repair of type A aortic dissection. J Thorac Cardiovasc Surg . 2020;159:1694-1703 e1693 . 3. Suzuki T, Isselbacher EM, Nienaber CA, Pyeritz RE, Eagle KA, Tsai TT, et al. Type-selective benefits of medications in treatment of acute aortic dissection (from the International Registry of Acute Aortic Dissection [IRAD]). Am J Cardiol . 2012;109:122-7 . 4. Melby SJ, Zierer A, Damiano RJ Jr, Moon MR. Importance of blood pressure control after repair of acute type a aortic dissection: 25-year follow-up in 252 patients. J Clin Hypertens (Greenwich). . 2013;15:63-8 . 5. Zierer A, Voeller RK, Hill KE, Kouchoukos NT, Damiano RJ Jr, Moon MR. Aortic enlargement and late reoperation after repair of acute type A aortic dissection. Ann Thorac Surg . 2007;84:479-86; discussion 486-477 . 6. Lee CC, Lee MG, Hsieh R, Porta L, Lee WC, Lee SH, et al. Oral Fluoroquinolone and the Risk of Aortic Dissection. J Am Coll Cardiol . 2018;72:1369-78 . 7. Lee CC, Lee MT, Chen YS, Lee SH, Chen YS, Chen SC, et al. Risk of Aortic Dissection and Aortic Aneurysm in Patients Taking Oral Fluoroquinolone. JAMA Intern Med . 2015;175:1839-47 . 8. Vouga Ribeiro N, Gouveia Melo R, Guerra NC, Nobre A, Fernandes RM, Pedro LM, et al. Fluoroquinolones Are Associated With Increased Risk of Aortic Aneurysm or Dissection: Systematic Review and Meta-analysis. Semin Thorac Cardiovasc Surg . 2020 . 9. LeMaire SA, Zhang L, Luo W, Ren P, Azares AR, Wang Y, et al. Effect of Ciprofloxacin on Susceptibility to Aortic Dissection and Rupture in Mice. JAMA Surg . 2018;153:e181804 . 10. LeMaire SA, Zhang L, Zhang NS, Luo W, Barrish JP, Zhang Q, et al. Ciprofloxacin accelerates aortic enlargement and promotes dissection and rupture in Marfan mice. The Journal of Thoracic and Cardiovascular Surgery . 2020 . 11. Fann JI, Smith JA, Miller DC, Mitchell RS, Moore KA, Grunkemeier G, et al. Surgical management of aortic dissection during a 30-year period. Circulation . 1995;92:II113-21 . 12. Evangelista A, Flachskampf FA, Erbel R, Antonini-Canterin F, Vlachopoulos C, Rocchi G, et al. Echocardiography in aortic diseases: EAE recommendations for clinical practice. Eur J Echocardiogr . 2010;11:645-58 . 13. Iliceto S, Ettorre G, Francioso G, Antonelli G, Biasco G, Rizzon P. Diagnosis of aneurysm of the thoracic aorta. Comparison between two non invasive techniques: two-dimensional echocardiography and computed tomography. Eur Heart J . 1984;5:545-55 . 14. Khandheria BK, Tajik AJ, Taylor CL, Safford RE, Miller FA Jr, Stanson AW, et al. Aortic dissection: review of value and limitations of two-dimensional echocardiography in a six-year experience. J Am Soc Echocardiogr . 1989;2: 17-24 . 15. Mintz GS, Kotler MN, Segal BL, Parry WR. Two dimensional echocardiographic recognition of the descending thoracic aorta. Am J Cardiol . 1979; 44:232-8 . 16. Albornoz G, Coady MA, Roberts M, Davies RR, Tranquilli M, Rizzo JA, et al. Familial thoracic aortic aneurysms and dissections–incidence, modes of inheritance, and phenotypic patterns. Ann Thorac Surg . 2006;82:1400-5 . 17. Roshanali F, Mandegar MH, Yousefnia MA, Mohammadi A, Baharvand B. Abdominal aorta screening during transthoracic echocardiography. Echocardiography . 2007;24:685-8 . 18. Verhagen JMA, Kempers M, Cozijnsen L, Bouma BJ, Duijnhouwer AL, Post JG, et al. Expert consensus recommendations on the cardiogenetic care for patients with thoracic aortic disease and their first-degree relatives. Int J Cardiol . 2018; 258:243-8 . 19. Bekkers SC, Habets JH, Cheriex EC, Palmans A, Pinto Y, Hofstra L, et al. Abdominal aortic aneurysm screening during transthoracic echocardiography in an unselected population. J Am Soc Echocardiogr . 2005;18: 389-93 . 20. Loeys B, Nuytinck L, Delvaux I, De Bie S, De Paepe A. Genotype and phenotype analysis of 171 patients referred for molecular study of the fibrillin-1 gene FBN1 because of suspected Marfan syndrome. Arch Intern Med . 2001;161:2447-54 . 21. Ma WG, Chou AS, Mok SCM, Ziganshin BA, Charilaou P, Zafar MA, et al. Positive family history of aortic dissection dramatically increases dissection risk in family members. Int J Cardiol . 2017;240:132-7 .

Key Words: acute type A aortic dissection, ATAAD, expert consensus document, ECD

APPENDIX E1: LITERATURE REVIEW METHODOLOGY

a. Detailed results of literature search

|Literature search author||| |---|---|---| |Michelle R. Demetres, MLIS||| | Scholarly Communications Librarian||| |Weill Cornell Medicine||| |Samuel J. Wood Library and C.V. Starr Biomedical Information Center,||| |New York, New York||| |Total Ovid MEDLINE|Total Ovid MEDLINE|Total Ovid MEDLINE| || searches | publications reviewed| |Section 1||347| | Section 2||126| |Section 3||1356| | Section 4||2418| |Section 5| ¥10 |3962| | Section 6||1006| |Section 7||1656| | Section 8||SS| |Total|35|11,428|

b. MEDLINE search – exemplary details

Transfer to Aortic Center Ovid MEDLINE (ALL – 1946 – October 1, 2020) Searched on October 5, 2020 No language, publication date, or article type restriction

|||Number| |---|---|---| |Iine||Search of results| ||Aneurysm, Dissecting/|17,888| ||Aortic Aneurysm/|21,503| ||Aortic Aneurysm, Thoracic/|12,521| || (acute type A adj2 (aortic or aorta or dissecti*)).tw. |1834| ||acute Stanford type A aortic dissection*.tw.|110| ||(ATAD or ATAAD or TAAD).tw.|476| ||acute aortic syndrome.tw.|373| ||thoracic aortic dissecti*.tw.|639| ||0r/1-8|40,298| |¥1O|Hospitals, High-Volume/|1605| || (high* volume adj3 (surgeon* or hospital* or center*)).tw. |6144| || (aortic center* or aortic treatment center*).tw. |8T| |¥13|aortic dissection team*.tw.|| |14|or/10-13|6985| ||9 and 14|1２Ｓ|

Surgical Repair of the Distal Anastomosis of the Aorta

Ovid MEDLINE (ALL – 1946-December 8, 2020) Searched on December 8, 2020 No language, publication date or article type restrictions

|Iine Search| |---| | (distal anastomosis or (distal aorta or distal aortic) adj3 anastomosis)).tw. | | (surgery or surgeries or surgical or operation or operate or operations).ti. 1and 2 |

TOTAL: 307

Initial Step for Visceral Malperfusion Occurring After Initial ATAAD Surgery?

Ovid MEDLINE (ALL – 1946-present) Searched on January 29, 2021 No language, publication date or article type restrictions

|Line Search|| |---|---| ||Aneurysm, Dissecting/| ||Aortic Aneurysm/| ||Aortic Aneurysm, Thoracic/| ||(acute type A adj2 (aortic or aorta or dissecti*)).tw.| ||acute Stanford type A aortic dissection*.tw.| ||(ATAD or ATAAD or TAAD).tw.| ||acute aortic syndrome.tw.| ||thoracic aortic dissecti*.tw.| |9|0r/1-8| |¥10| (visceral malperfusion* or visceral ischaemia* or end organ maleperfusion*).tw. | |11 9 and 10|11 9 and 10|

TOTAL: 78

Aortic Root Management in Patients With ATAAD and Marfan Syndrome

Ovid MEDLINE (ALL – 1946 – November 30, 2020) Searched on December 1, 2020 Nolanguage, publication date or article type restrictions

|Line Search| |---| |Aneurysm, Dissecting/| |Aortic Aneurysm/| |Aortic Aneurysm, Thoracic/| |(acute type A adj2 (aortic or aorta or dissecti*)).tw.| |acute Stanford type A aortic dissection*.tw.| |(ATAD or ATAAD or TAAD).tw.|

Continued

|Line Search| |---| |acute aortic syndrome.tw.| |thoracic aortic dissecti*.tw.| |0r/1-8| |10 Marfan Syndrome/| |(marfan or marfans or *Marfan's").tw.| |10 or 11| |13 9and12| |(aortic or aorta) adj3 root).tw.| |13and14|

TOTAL: 563