key: cord-1021940-5ykvs73x
authors: Sabe, Ashraf A.; Percy, Edward; Kaneko, Tsuyoshi; Plichta, Ryan P.; Hughes, G. Chad
title: When to Consider Deferral of Surgery in Acute Type A Aortic Dissection: A Review
date: 2020-08-31
journal: Ann Thorac Surg
DOI: 10.1016/j.athoracsur.2020.08.002
sha: d1d7f0a58ff53fe20d6a65e3ab1d74f52189ba5f
doc_id: 1021940
cord_uid: 5ykvs73x

Background Acute type A aortic dissection (ATAAD) is a surgical emergency with an operative mortality of up to 30%, a rate which has not changed meaningfully in over two decades. A growing body of research has highlighted several comorbidities and presenting factors in which delay or permanent deferral of surgery may be considered; however, modern comprehensive summative reviews are lacking. The urgency and timing of this review are underscored by significant challenges in resource utilization posed by the COVID-19 pandemic. This review provides an update on the current understanding of risk assessment, surgical candidacy, and operative timing in patients with ATAAD. Methods A literature search was conducted through PubMed and Embase databases to identify relevant studies relating to risk assessment in ATAAD. Articles were selected via group consensus based on quality and relevance. Results Several patient factors have been identified which increase risk in ATAAD repair. In particular, frailty, advanced age, prior cardiac surgery, and use of novel anticoagulant medications have been studied. The understanding of malperfusion syndromes has also expanded significantly, including recommendations for surgical delay. Finally, approaches to triage have been significantly influenced by resource limitations related to the ongoing COVID-19 pandemic. While medical management remains a reasonable option in carefully selected patients at prohibitive risk for open surgery, endovascular therapies for treatment of ATAAD are rapidly evolving. Conclusions Early surgical repair remains the preferred treatment for most patients with ATAAD, however, improvements in risk stratification should guide appropriate delay or permanent deferral of surgery in select individuals.

Acute type A aortic dissection (ATAAD) is a surgical emergency, with a mortality rate of up to 90% in patients who do not receive timely operative intervention. [1] [2] [3] Despite significant advances in imaging, perioperative care, and surgical technique, operative mortality rates have remained relatively unchanged between 10% and 30% over the past 2 decades (Figure 1 ). [4] [5] [6] Given this relative stagnation in rates of morbidity and mortality associated with ATAAD repair, recent studies have focused on the identification of factors important for risk stratification in this population. Furthermore, new options for endovascular management have emerged and are evolving to become efficacious treatment options for carefully selected individuals with ATAAD. 7 Finally, in the era of the COVID-19 pandemic, traditional algorithms for the treatment of surgical emergencies must be carefully challenged and re-examined with a focus on minimizing infectious spread, and timely and appropriate resource allocation. 8 The aim of this review is to provide a commentary on contemporary approaches to the identification of high-risk features in ATAAD, and when delay, permanent deferral of surgical treatment, or transfer to a specialized center may be considered ( Table 1) .

Articles discussed in this narrative review were identified through a literature search of English language articles in PubMed (1946-present) and Embase (1974-present) , last updated April 25, 2020 . The search strategy focused on the identification of articles studying contemporary factors influencing outcomes of ATAAD repair: frailty, age, malperfusion, malperfusion syndrome, prior cardiac surgery, anticoagulant medications, and risk stratification tools. Additionally, current articles regarding the ongoing COVID-19 pandemic were identified through additional search of in-press articles in relevant surgical and cardiothoracic surgical journals. Articles were selected by the authors based on quality and relevance.

J o u r n a l P r e -p r o o f Frailty is a multidimensional syndrome involving loss of reserve across multiple systems, leading to increased vulnerability. 9 Although several scoring systems and measurement tools have been developed, assessing frailty in the setting of ATAAD remains a significant challenge given the typically emergent presentation. Consequently, research on the effects of frailty in ATAAD is limited. Nonetheless, frailty assessment in elective proximal aortic surgery has proven useful in the prediction of mortality and discharge disposition. 10, 11 In patients presenting with ATAAD who are at risk for frailty, it remains important to evaluate global functional status, activities of daily living, and comorbid conditions. Several comorbidities, including cerebrovascular disease and severe chronic lung disease, have been shown to be independent predictors for 30-day mortality after ATAAD repair and these risks are likely exacerbated in the presence of frailty. 12, 13 In the absence of validated frailty tools in this patient group, advanced age is often considered as a surrogate. Importantly, there is likely to be a significant increase in the number of elderly patients presenting with acute aortic syndromes, in light of the aging population. 14 While many elderly patients do have significant functional limitations, there is not convincing evidence for a "hard" age cut-off with respect to surgery for ATAAD. In fact, several groups have found good short-term outcomes in healthy octogenarians. 15, 16 It is important to note, however, that prior work has suggested that long-term survival in elderly patients may not be improved compared to those managed medically (Figure 2 ). 17 In elderly individuals with comorbidities or decreased functional status, medical management is a very reasonable course of action. Open and honest communication of both short-and long-term outcomes, along with discussions of goals of care, are very important in this patient group.

J o u r n a l P r e -p r o o f Malperfusion occurs in 16% to 33% of patients presenting with ATAAD. 1 The presence of clinically apparent malperfusion in any organ system at presentation is an ominous sign, which is associated with increased mortality. 18 For example, Lawton et al. demonstrated that patients with malperfusion and severe acidosis had an operative mortality of 92%. 19 The distinction between malperfusion and malperfusion syndrome (MPS) is critically important in the optimization of treatment and operative planning. Malperfusion alone has been defined as "inadequate blood flow to the end organs because of dissection related obstruction of the aorta and its branches", whereas MPS is defined as "tissue necrosis and failure of vital organs (such as viscera or lower extremity) secondary to late-stage malperfusion". 20, 21 As such, the diagnosis of MPS requires the presence of both clinical features (e.g.: abdominal pain, tenderness, oliguria or anuria, motor or sensory neurovascular deficits) and laboratory features (e.g.: elevated lactate, serum creatinine, liver or pancreatic enzymes, creatinine kinase) indicative of end-organ ischemia.

The presence of MPS indicates active end-organ ischemia and can itself lead to significant exacerbation of the inflammatory cascade, further complicating management in these individuals. Mesenteric MPS is of particular concern, with a reported mortality rate of 60% or higher in multiple series. Even with early intervention, the mortality rate in these patients is still up to 42%. 22 In light of this, many groups have adopted treatment algorithms which delay operative repair of the proximal aorta in the setting of MPS.

The University of Michigan group was first to describe a novel strategy of operative delay for the treatment of MPS in ATAAD. Their initial landmark study compared the traditional standard of care approach of immediate proximal aortic repair with a cohort managed with initial percutaneous intervention restoring true lumen flow, followed by delayed operative ATAAD repair after resolution of malperfusion injury. 20 The mortality rate in the historic cohort treated with immediate aortic repair was 89% compared to only 25% in the group managed with delayed repair after restoring end-organ perfusion (P=0.003). In the years since this initial J o u r n a l P r e -p r o o f series, their group has consistently shown the benefits of this strategy and have demonstrated a 95% success rate in treating malperfused vascular beds percutaneously. 23 More current techniques, involving the use of thoracic endovascular aortic repair (TEVAR) as the initial step for restoration of flow in MPS, have been successful in comparison to prior fenestration-based strategies. 24, 25 Additionally, the PETTICOAT (Provisional Extension To Induce Complete Attachment) technique has also been considered in ATAAD as a means of correcting malperfusion, although this technique requires further study. 26, 27 A standardized algorithm has been developed to summarize the approach in those without aortic rupture or tamponade ( Figure 3 ). 28 Importantly, the safety of various time periods for surgical delay in these patients has not been definitely shown. However, important patterns can be inferred from previous research on the timing of surgical repair. In 2013, Booher et al. used the International Registry of Acute Aortic Dissection (IRAD) database to examine a novel classification system for dissection timing. 29 After controlling for delays to initial presentation, they found that longer delays to operative repair were associated with lower follow-up mortality. In this context, their data suggests that patients with MPS who may not initially be surgical candidates but do survive initial MPS management may have favorable surgical outcomes if repair is undertaken in a delayed fashion. In some patients, this may even include delaying repair to the chronic setting in the event that their recovery from MPS is prolonged.

In summary, MPS carries a high risk of morbidity and mortality. Careful workup and patient selection are important in determining optimal procedural approaches to ATAAD repair in these individuals. Operative patients presenting with ATAAD and radiographic concern for malperfusion, but without clear evidence of resultant end-organ dysfunction, are still best treated with the immediate ATAAD repair. In patients with MPS who are otherwise operative candidates, delayed repair of the ATAAD is recommended after reversing clinically apparent mesenteric or limb MPS in centers with adequate and timely access to these techniques.

Otherwise, in patients with MPS and no evidence of tamponade, transfer to an institution with these capabilities may be the best approach. 30

Patients with cerebral malperfusion (CM) represent a unique subset in which treatment decisions are particularly challenging. CM occurs in 7% to 15% of ATAAD and is associated with short term mortality as high as 50% as well as poor long-term survival. [31] [32] [33] A study from the IRAD database found that patients with CM who underwent surgery for ATAAD had a higher incidence of postoperative cerebrovascular accident (17.5% vs. 7.2%, p < 0.001) and in-hospital mortality (25.7% vs. 12%, p < 0.001) than those without CM undergoing surgery. 34 Hemorrhagic conversion of an ischemic insult during systemic anticoagulation for cardiopulmonary bypass is a significant concern, which complicates decisions regarding immediate or delayed operative management. 35, 36 Despite the morbidity of CM in the setting of ATAAD, several studies have demonstrated that early intervention in these individuals can result in improved mortality and significant neurologic recovery. [37] [38] [39] In one study by Di Eusanio et al. utilizing data from IRAD, 84% of patients with stroke and 79% of patients presenting with coma had reversal of brain injury after surgery. 31 Additionally, a recent multicenter study found that 62% of patients with preoperative neurologic deficit had no to moderate postoperative deficits. Notably, patient age (odds ratio 1.041; P = 0.02) and history of prior stroke (odds ratio 2.651; P = 0.03) were predictive of poor clinical outcome; however, presenting with coma was not. Hemorrhagic conversion occurred in only 7 (5%) patients and no independent predictors of this complication were identified. 40 Patients with ATAAD and CM who undergo surgery should be carefully selected by an experienced multidisciplinary team based on age, frailty, comorbidities, hemodynamic stability, and extent of other malperfusion syndromes. Preoperative cerebral imaging can aid prognostication, as demonstration of a large infarct or occluded internal carotid artery may J o u r n a l P r e -p r o o f predict a worse neurologic outcome. 40 When experienced clinical evaluation otherwise portends a favorable prognosis, early surgery may be performed with reasonable rates of survival and reversal of cerebral ischemia, including patients presenting with coma. Ultimately, this is an evolving realm and given recent data, including case reports describing advances in percutaneous intervention prior to surgery, decisions should be considered on a case-by-case basis. 40, 41 Prior Cardiac Surgery Sternal re-entry in patients with prior cardiac surgery poses technical challenges associated with mediastinal adhesions, increased bleeding, as well as the risk of injury to existing bypass grafts if the prior operation included coronary bypass grafting. 42 While there were previous thoughts that fibrotic scarring from prior surgery would provide some protection from tamponade and rupture in ATAAD, this has not consistently proven to be the case in larger database studies. 43 Several studies have examined the outcomes of patients with prior cardiac surgery undergoing repair of ATAAD. One such study found no significant difference in 30-day morbidity or mortality in 50 patients who had previous cardiac surgery as compared to those from the same era without prior surgery. 44 In contrast, in a recent much larger study utilizing the repair in patients with prior cardiac surgery was associated with a greater than 2-fold higher risk of mortality compared to those without prior cardiac surgery (odds ratio 2.1; p< 0.01). 45 There was a trend towards decreased operative mortality for patients with prior cardiac surgery undergoing ATAAD repair at high-volume centers (25.7% vs. 37.9%, p = 0.19). In summary, the currently available evidence suggests that patients with ATAAD and prior cardiac surgery J o u r n a l P r e -p r o o f require careful deliberation, adequate pre-operative planning and potential consideration for transfer to high-volume centers.

The use of novel/non-vitamin K oral anticoagulants (NOACs), also termed direct oral anticoagulants (DOACs), has increased dramatically over the past decade. 46 Given the absence of reliable reversal agents for several of these medications, they can present significant risks to patients requiring emergent cardiovascular surgery. Studies of their use related to ATAAD are limited to small single center experiences or case reports. While adequate reversal of anticoagulation has been achieved in several cases, outcomes in general remain variable and high-quality data is lacking. 47 In 2018, Hamad et al. did report two successful cases of urgent reversal confirmed by thromboelastometry monitoring in patients on rivaroxaban and dabigatran, whose procedures were delayed by 60 hours and 40 hours, respectively. 48 Antidotes for specific NOACs have been approved in recent years. Specifically, idarucizumab has been approved as a reversal agent for dabigatran, and andexenat alfa is approved as a reversal agent for rivaroxaban and apixaban. 49 Idarucizumab, a monoclonal antibody fragment, has been given prior to heart transplant with useful effect in a small case series. 50 Andexanet alfa acts as a factor Xa decoy, thus significantly reducing (but not eliminating) anticoagulant activity by binding and sequestering apixaban and rivaroxaban. Its use in the setting of emergent cardiac surgery, particularly with cardiopulmonary bypass, has been described in case reports but requires further investigation. 51 It is important to note that andexanet alfa reverses factor Xa inhibitor levels for ~2-3 hours, after which levels return to baseline. 52 We recommend a multimodal approach in select patients requiring emergent surgery for ATAAD on NOACs. Patient comorbidities and planned extent of operation should be carefully considered, as should other known risk factors for bleeding in proximal aortic repair. 53 

Depending on institutional capability, initial options include delayed surgical repair until half-life clearance of the agent, global coagulation assay, thromboelastometry assays, or preferably direct measurements of anti-factor Xa levels. Post cardiopulmonary bypass options to treat coagulopathy include use of antifibrinolytics, standard blood products such as platelets, fresh frozen plasma, and cryoprecipitate, as well as recombinant factors such as prothrombin complex concentrate, activated factor VIIa, human fibrinogen concentrate, and thoughtful administration of anti-Xa antidotes. 54, 55 

Patient-centered decision making is of utmost importance in ATAAD, given the high-risk nature of this condition. Providers must have open and thoughtful discussion of risks and benefits of all available options, including medical management. Discussions around the use of blood products and overall goals of care are paramount in a patient-centered decision-making process.

In rare cases, patients may wish to avoid transfusion of blood products for personal or religious reasons. Favorable outcomes have been demonstrated in studies of Jehovah's Witness patients undergoing elective cardiac surgery with appropriate preoperative planning. 56, 57 However, in the setting of ATAAD, which is associated with a high rate of transfusion, the reluctance to receive blood products poses potentially lethal challenges in perioperative management. 33 In select patients, delaying surgery to allow clear counseling on the risks of refusing transfusion may be necessary to obtain informed consent and optimize patient outcomes. Importantly, one must not assume that any individual will uniformly refuse transfusion of any products until properly counseled on the available choices. Furthermore, treatment with J o u r n a l P r e -p r o o f purified proteins derived from plasma is acceptable to many patients. 58 Options which may be acceptable to patients include treatment with albumin, activated factor VIIa, factor eight inhibitor bypass activity (FEIBA), prothrombin complex concentrate, and human fibrinogen concentrate. 59 Consideration should be given to limiting the scope of the operation with avoidance of prolonged cardiopulmonary bypass times and deep cooling, strict attention to surgical hemostasis, liberal use of recombinant hemostatic factors to facilitate clotting, and vigilant postoperative blood pressure control with early return to the operating room for surgical control of bleeding. 60 Finally, initial medical management for stabilization and correction of the acute inflammatory cascade, followed by delayed surgical repair may be appropriate in some individuals. 61 

Whether operative or non-operative management is planned in patients with ATAAD, the patient and their family should be clearly counseled on "best-case/worst-case" scenarios and clear goals-of-care discussions should be undertaken. In a recent Veteran's Administration study evaluating 95,204 patients who underwent high-risk surgery, only 770 (0.8%) received a palliative care consultation before surgery. 62 Of all the patients who died within 90 days, 29.9% had received a palliative care consultation, with 5.6% having received consultation before surgery. Families of these patients reported an overall significant increase in satisfaction with end-of-life care, communication and support. While challenging in the acute care setting, goals of care should always be carefully considered for those presenting with ATAAD.

In addition to patient-level factors, the ongoing COVID-19 pandemic has highlighted how external forces and hospital resources can influence treatment decisions in patients undergoing complex procedures. As of July 11th, 2020 there were over 12.6 million confirmed cases worldwide, placing an immense strain on healthcare systems around the globe. 63 Additionally, J o u r n a l P r e -p r o o f there has been evidence of significant decreases in the volume of patients presenting with acute dissection. In New York, El-Hamamsy et al. reported a 76.5% decrease in expected volume, raising concerns that patients may not be seeking timely care and the potential for increases in complex delayed presentations. 64 In the setting of acute pathology such as ATAAD, this pandemic has introduced an additional layer of complexity with regard to operative decision making. In particular, increasingly limited intensive care resources, redeployment of cardiovascular team members, and limitations on inpatient space have reduced the availability of several key elements required to perform resource intensive ATAAD repair. Formal triage committees are being established in some jurisdictions to aid with challenging decisions regarding scarce resource distribution. 65 Recently, the STS COVID-19 Taskforce released a guidance statement which considers four levels of tiered case triage based on the impact of COVID-19 on hospital-wide resources. 66 In the most extreme fourth tier, emergent conditions such as ATAAD are still performed according to resource availability; however, those patients who are considered stable and capable of waiting are deferred until adequate resources can be ensured. In cases of ATAAD in a resource limited setting, transfer of hemodynamically stable individuals to hospitals with greater immediate capacity may be necessary. In an effort to help surgeons estimate and plan for resource allocation, the STS has also launched a "Resource Utilization Tool" (https://www.sts.org/resources/resource-utilization-tool). This application allows surgeons to estimate operative time, ventilator time, length of stay and other factors. These systems will be critically important for decisions regarding allocation of limited hospital resources.

Each health system and hospital will face varying pressures throughout this pandemic and will need to make difficult decisions regarding their ability to allocate resources and perform complex procedures. 67 Currently, at both Brigham and Women's Hospital and Duke University Medical Center, patients needing urgent surgery, including ATAAD, are screened for symptoms J o u r n a l P r e -p r o o f or exposure to COVID-19, and a rapid (15-45 minute) COVID-19 test is sent upon admission to the hospital. Barring any systemic resource availability concerns, the patient is taken without delay to the operating room and the entire perioperative staff provided with protective personal equipment including N-95 masks and face shields until the test results are available, which typically will result before a skin incision is made. Importantly, there should be no COVID-related delay of transport to the operating room for otherwise operable ATAAD patients.

Operative decision making must remain fluid in response to the constant changes induced by the current pandemic. In patients with ATAAD and complications such as tamponade or coronary ischemia, emergency repair remains the best available option. In patients with more stable presentations, as outlined above, surgeons may consider permanent deferral of surgery or temporary delay until adequate resource planning can be managed. 

While aortic valve re-suspension with supracoronary ascending aorta and hemiarch replacement with circulatory arrest remains the gold standard approach in the majority of patients with ATAAD, other surgical options exist and may be of use in patients who cannot tolerate lengthy complex procedures. Replacement of the ascending aorta alone, without extension to hemiarch or total arch, has been studied previously. While this procedure is associated with higher 30-day mortality 13 , it has been employed in select individuals in whom there may be advantages to avoiding an open distal repair with circulatory arrest. Furthermore, while total arch replacement has been preferred in some high-volume centers for patients with arch vessel involvement, a more conservative approach may suffice in many scenarios. 71 In patients who are not surgical candidates, medical management has traditionally been the only alternate strategy available; however, interventional catheter-based options have emerged over the past decade and may be of use in select individuals. Off-label and investigational applications of TEVAR in the ascending aorta have been applied to treat ATAAD.

Despite being a higher risk patient population, small studies have demonstrated technical success, early mortality rates below 15%, and relatively low aorta-related mortality rates in the long-term. [72] [73] [74] Much more research and technological innovation is required before endovascular repair can be considered for widespread use. However, there is promise for these techniques in patients at prohibitive risk for traditional ATAAD repair.

Finally, medical management remains an option for a significant proportion of patients with ATAAD who are not surgical candidates. Recent data from the IRAD database demonstrates that definitive medical management may be a reasonable option in certain highrisk patients, with 30-day survival rates of nearly 40% with medical management alone. 75 Predictors of success with medical management in ATAAD included prior cardiac surgery, normal admission chest x-ray, presenting hypertension, non-white race and most proximal dissection extent limited to the ascending aorta without root involvement (Figure 4) . 75 

Considering the complex and high-risk presentations associated with ATAAD, riskstratification tools have been developed. The most well validated of these tools is the "Penn Classification", which stratifies patients according to ischemic malperfusion pattern. 76 Specifically, this system stratifies risk according to the presence or absence of branch-vessel malperfusion, circulatory collapse, or both. While the Penn Classification has performed well in J o u r n a l P r e -p r o o f validation studies, its clinical application remains challenging due to the broad range of presentations in patients with ATAAD. Another clinically-based tool, developed from the IRAD database, incorporates pre-and intra-operative variables to yield a simple risk model with very good utility in predicting death in ATAAD. 77 These scoring systems have utility in their ability to offer rapid estimates of operative mortality, however, they should be used with caution and careful clinical correlation. One important component which is recognized by both scoring systems is the concept of hemodynamic instability or circulatory collapse in the pre-operative period. Several studies have found pre-operative shock or hemodynamic instability to be associated with significantly higher operative mortality. [78] [79] In the IRAD tool, the presence of hypotension (systolic pressure <100 mm Hg) or shock with or without tamponade (systolic pressure <80 mmHg) was independently predictive of operative mortality (odds ratio 3.23). 77 Furthermore, those with cardiac arrest prior to surgery are at particularly high risk. In a recent study of patients with ATAAD undergoing cardiopulmonary resuscitation, Uehara et al. showed that duration of resuscitation greater than 15 minutes was an extremely strong independent predictor for operative mortality following surgical repair (hazard ratio 8.27). 80 In the context of these scoring systems, the presence of hemodynamic instability or collapse should be viewed as an ominous sign, with longer durations potentially serving as a relative contraindication to operative repair.

ATAAD remains a life-threatening condition, with or without surgery. Though our understanding of risk assessment has improved in recent years, clinical decisions remain J o u r n a l P r e -p r o o f 

Evidence, lack of evidence, controversy, and debate in the provision and performance of the surgery of acute type A aortic dissection

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Modifiable Risk Factors for Early Mortality in Low-Risk Penn Class Aa Acute Type A Aortic Dissection Patients --A Descriptive Study

Contemporary Results of Surgery in Acute Type A Aortic Dissection: The International Registry of Acute Aortic Dissection Experience

Thoracic endovascular aortic repair (TEVAR) in proximal (type A) aortic dissection: Ready for a broader application

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A global clinical measure of fitness and frailty in elderly people

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Contemporary Results for Proximal Aortic Replacement in North America

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Faculty of 1000 evaluation for Early and late surgical outcomes of acute type A aortic dissection in octogenarians. F1000 -Post-publication peer Rev Biomed Lit

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Acute type A dissection in octogenarians: does emergency surgery impact in-hospital outcome or long-term survival?

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Surgical Delay for Acute Type A Dissection With Malperfusion

Managing patients with acute type A aortic dissection and mesenteric malperfusion syndrome: A 20-year experience

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

Treatment for malperfusion syndrome in acute type A and B aortic dissection: A long-term analysis

The TEVAR-First Approach to DeBakey I Aortic Dissection With Mesenteric Malperfusion

STABLE II clinical trial on endovascular treatment of acute, complicated type B aortic dissection with a composite device design

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The IRAD classification system for characterizing survival after aortic dissection

Interfacility Transfer of Medicare Beneficiaries With Acute Type A Aortic Dissection and Regionalization of Care in the United States

Patients with type A acute aortic dissection presenting with major brain injury: Should we operate on them?

Significance of malperfusion syndromes prior to contemporary surgical repair for acute type A dissection: outcomes and need for additional revascularizations

Malperfusion in acute type A aortic dissection: An update from the Nordic Consortium for Acute Type A Aortic Dissection

Surgery for type A aortic dissection in patients with cerebral malperfusion: Results from the International Registry of Acute Aortic Dissection

Neurological outcomes after immediate aortic repair for acute type A aortic dissection complicated by coma

Acute type A aortic dissection complicated by stroke: can immediate repair be performed safely?

Analysis of risk factors for neurological dysfunction in patients with acute aortic dissection type A: data from the German Registry for Acute Aortic Dissection type A (GERAADA)

Is acute type A aortic dissection a true surgical emergency?

Creation of a Scorecard to Predict In-Hospital Death in Patients Undergoing Operations for Acute Type A Aortic Dissection

Preoperative neurological deficit in acute type A aortic dissection

Novel Percutaneous Treatment of Cerebral Malperfusion Before Surgery for Acute Type A Dissection

Incidence and outcome of reentry injury in redo cardiac surgery: Benefits of preoperative planning

Outcomes of Patients Presenting With Acute Type A Aortic Dissection in the Setting of Prior Cardiac Surgery: An Analysis From the International Registry of Acute Aortic Dissection

Is previous cardiac surgery a risk factor for open repair of acute type A aortic dissection?

Outcomes After Acute Type A Aortic Dissection in Patients With Prior Cardiac Surgery

Variation in the Use of Warfarin and Direct Oral Anticoagulants in Atrial Fibrillation and Associated Cost Implications

Reversal of DIRECT-ACTING Oral Anticoagulants in Urgent Surgery of the Proximal Aorta: Case Series and Review of the Literature

Delayed surgery in patients with acute type A aortic dissection who are receiving novel oral anticoagulants

Reversal agents for direct oral anticoagulants: considerations for hospital physicians and intensivists

Dabigatran reversal with idarucizumab in a patient undergoing heart transplantation: first European report

Andexanet Alfa for Urgent Reversal of Apixaban Before Aortic Surgery Requiring Cardiopulmonary Bypass. A A Pract

Reversal agents for non-vitamin K antagonist oral anticoagulants

Predictors of massive transfusion with thoracic aortic procedures involving deep hypothermic circulatory arrest

Protocolized hemostatic factor use in major thoracic aortic surgery

Activated prothrombin complex concentrate to reverse the factor Xa inhibitor (apixaban) effect before emergency surgery: a case series

Cardiac surgery in Jehovah's Witness patients: tenyear experience

Results of open heart surgery in Jehovah's Witness patients. Single centre experience

The contemporary approach to the care of Jehovah's witnesses

Evaluation of postoperative clinical outcomes in Jehovah's Witness patients who receive prothrombin complex concentrate during cardiac surgery

Bloodless surgery of acute type A aortic dissection in a Jehovah's Witness patient

Repair of Type A Dissection in a Jehovah's Witness With Prior Cardiac Operation

Palliative Care and End-of-Life Outcomes Following High-Risk Surgery

An interactive web-based dashboard to track COVID-19 in real time

The COVID-19 Pandemic and Acute Aortic Dissections in New York: A Matter of Public Health

The Toughest Triage -Allocating Ventilators in a Pandemic

Adult cardiac surgery during the COVID-19 Pandemic: A Tiered Patient Triage Guidance Statement

Fair Allocation of Scarce Medical Resources in the Time of Covid-19

Acute Type A Aortic Dissection Complicated by COVID-19 Infection

Clinical course of patients infected with SARS-CoV-2 soon after thoracoscopic lung surgery

Dissection of Arch Branches Alone: An Indication for Aggressive Arch Management in Type A Dissection?

A systematic review of primary endovascular repair of the ascending aorta

Thoracic endovascular aortic repair for the ascending aorta: experience and pitfalls

Outcomes of Endovascular Repair of Ascending Aortic Dissection in Patients Unsuitable for Direct Surgical Repair

Predicting In-Hospital Survival in Acute Type A Aortic Dissection Medically Treated

Mortality in acute type A aortic dissection: Validation of the Penn classification

Simple Risk Models to Predict Surgical Mortality in Acute Type A Aortic Dissection: The International Registry of Acute Aortic Dissection Score

Preoperative Shock Determines Outcome for Acute Type A Aortic Dissection

Impact of Hemodynamic Instability and Organ Malperfusion in Elderly Surgical Patients Treated for Acute Type A Aortic Dissection

Surgical Outcomes of Acute Type A Aortic Dissection in Patients Undergoing Cardiopulmonary Resuscitation