The Year in Aortic Surgery: Selected Highlights From 2023.

This article reviews the recent and relevant literature to the field of aortic surgery. Specific areas highlighted include outcomes of Stanford type A dissection, management of acute aortic syndromes, management of aortic aneurysms, and traumatic aortic injury. Although the focus was on articles from 2023, literature from prior years also was included, given that this article is the first of a series. Notably, the pertinent sections from the 2022 American College of Cardiology/American Heart Association Guidelines for the Diagnosis and Management Aortic Disease are discussed.

Effectiveness of Proximal Landing Zone 1 and 2 Thoracic Endovascular Aortic Repair for Type B Aortic Dissection by Comparing Outcomes With Thoracic Arch Aneurysm.

PURPOSE: Hybrid thoracic endovascular aortic repair (TEVAR) for aortic arch aneurysms is a minimally invasive procedure with improved results. This study aimed to clarify the effectiveness and expand the possibilities of zone 1 and 2 landing TEVAR for type B aortic dissection (TBAD) using our treatment strategy. METHODS: This retrospective, single-center, observational cohort study included 213 patients (TBAD, n=69; thoracic arch aneurysm [TAA], n=144; median age, 72 years; median follow-up period, 6 years) from May 2008 to February 2020. The following conditions were satisfied before performing zone 1 and 2 landing TEVAR: TBAD; proximal landing zone (LZ): diameter <37 mm, length >15 mm, and nondissection area, proximal stent-graft: size ≤40 mm and oversizing rate: 10% to 20%, and TAA; proximal LZ: diameter ≤42 mm and length >15 mm, proximal stent-graft: size ≤46 mm and oversizing rate: 10% to 20%. Of the 69 patients in the TBAD group, 34 (49.3%) had patent false lumen (PFL), and 35 (50.7%) had false lumen partial thrombosis (FLPT), including ulcer-like projections. Emergency procedures were performed in 33 (15.5%) patients. RESULTS: There were no significant differences in the in-hospital mortality (TBAD: 1.5% vs TAA: 0.7%, p=0.544) or the in-hospital aortic complications (TBAD: n=1 vs TAA: n=5, p=0.666). Retrograde type A dissection was not observed in the TBAD group. The aortic event-free rates at 10 years were 89.7% (95% confidence interval [CI]: 78.7%-95.3%) and 87.9% (95% CI: 80.3%-92.8%) in the TBAD and TAA groups, respectively (log-rank p=0.636). In the TBAD group, the early and late outcomes were not significantly different between the PFL and FLPT groups. CONCLUSION: Satisfactory early and long-term results were obtained with zone 1 and 2 landing TEVAR. The TBAD cases had the same good results as the TAA cases. Using our strategy, we especially might reduce complications and be an effective treatment for acute complicated TBAD. CLINICAL IMPACT: This study aimed to clarify the effectiveness and expand the possibilities of zones 1 and 2 landing TEVAR for type B aortic dissection (TBAD) using our treatment strategy. Satisfactory early and long-term results in the TBAD and thoracic arch aneurysm (TAA) groups were obtained with zones 1 and 2 landing TEVAR. The TBAD cases had the same good results as the TAA cases. Using our strategy, we especially might reduce complications and be an effective treatment for acute complicated TBAD.

Implementation of a direct-to-operating room aortic emergency transfer program: Expedited management of type A aortic dissection.

INTRODUCTION: Type A Aortic Dissection (TAAD) is a surgical emergency with a time-dependent rate of mortality. We hypothesized that a direct-to-operating room (DOR) transfer program for patients with TAAD would reduce time to intervention. METHODS: A DOR program was started at an urban tertiary care hospital in February 2020. We performed a retrospective study of adult patients undergoing treatment for TAAD before (n = 42) and after (n = 84) implementation of DOR. Expected mortality was calculated using the International Registry of Acute Aortic Dissection risk prediction model. RESULTS: Median time from acceptance of transfer from emergency physician to operating room arrival was 1.37 h (82 min) faster in DOR compared to pre-DOR (1.93 h vs 3.30 h, p < 0.001). Median time from arrival to operating room was 1.14 h (72 min) faster after DOR compared to pre-DOR (0.17 h vs 1.31 h, p < 0.001). In-hospital mortality was 16.2% in pre-DOR, with an observed-to-expected (O/E) ratio of 1.03 (p = 0.24) and 12.0% in the DOR group, with an O/E ratio of 0.59 (p < 0.001). CONCLUSION: Creation of a DOR program resulted in decreased time to intervention. This was associated with a decrease in observed-to-expected operative mortality. The transfer of patients with acute type A aortic dissection to centers with direct-to-OR programs may result in decreased time from diagnosis to surgery.

"Big Data" Analyses Underlie Clinical Discoveries at the Aortic Institute.

This issue of the Yale Journal of Biology and Medicine (YJBM) focuses on Big Data and precision analytics in medical research. At the Aortic Institute at Yale New Haven Hospital, the vast majority of our investigations have emanated from our large, prospective clinical database of patients with thoracic aortic aneurysm (TAA), supplemented by ultra-large genetic sequencing files. Among the fundamental clinical and scientific discoveries enabled by application of advanced statistical and artificial intelligence techniques on these clinical and genetic databases are the following: From analysis of Traditional "Big Data" (Large data sets). 1. Ascending aortic aneurysms should be resected at 5 cm to prevent dissection and rupture. 2. Indexing aortic size to height improves aortic risk prognostication. 3. Aortic root dilatation is more malignant than mid-ascending aortic dilatation. 4. Ascending aortic aneurysm patients with bicuspid aortic valves do not carry the poorer prognosis previously postulated. 5. The descending and thoracoabdominal aorta are capable of rupture without dissection. 6. Female patients with TAA do more poorly than male patients. 7. Ascending aortic length is even better than aortic diameter at predicting dissection. 8. A "silver lining" of TAA disease is the profound, lifelong protection from atherosclerosis. From Modern "Big Data" Machine Learning/Artificial Intelligence analysis: 1. Machine learning models for TAA: outperforming traditional anatomic criteria. 2. Genetic testing for TAA and dissection and discovery of novel causative genes. 3. Phenotypic genetic characterization by Artificial Intelligence. 4. Panel of RNAs "detects" TAA. Such findings, based on (a) long-standing application of advanced conventional statistical analysis to large clinical data sets, and (b) recent application of advanced machine learning/artificial intelligence to large genetic data sets at the Yale Aortic Institute have advanced the diagnosis and medical and surgical treatment of TAA.

Toward endovascular treatment of type A aortic dissection with smaller landing zones and more patient eligibility.

OBJECTIVE: Type A or ascending aortic dissection is an acute life-threatening condition with high morbidity and mortality. Open surgery remains the standard of care. The development of minimally invasive endografts for type A aortic dissection (TAAD) will require a detailed understanding of the dissection and aortic root anatomy to determine patient eligibility and optimal device specifications. METHODS: Computed tomography images of TAAD cases at our institution from 2012 to 2019 were identified, and three-dimensional reconstructions were performed using OsiriX, version 10.0 (Pixmeo SARL, Bernex, Switzerland). We analyzed key anatomic structures, including centerline length measurements, ascending aorta and aortic root dimensions, and the location and extent of dissection in relationship to the coronary ostia. RESULTS: A total of 53 patients were identified (mean ± standard deviation age, 60.4 ± 17.1 years; 36 men and 17 women), 46 of whom had undergone surgery for TAAD. Four patients had died within 30 days of surgery. In 47 patients (88.7%), the entry tear was distal to the highest coronary ostium. These cases were retrospectively considered for endovascular intervention using a nonbranched, single endograft stent. The proximal landing zone (LZ) was defined as the distance from the highest coronary ostium to the entry tear. Of the 53 patients, 35 (66.0%) had a proximal LZ length of ≥2.0 cm, 38 (71.7%) had a proximal LZ length of ≥1.5 cm, and 42 (79.2%) had a proximal LZ length of ≥1.0 cm. The median proximal and distal LZ diameters of the sinotubular junction (STJ) and distal ascending aorta regions were 3.29 cm (interquartile range [IQR], 2.73-4.10 cm) and 3.49 cm (IQR, 3.09-3.87 cm, respectively), with a median length from the STJ to the innominate takeoff of 8.08 cm (IQR, 6.96-9.40 cm). The median ascending aorta radius of curvature was 6.48 cm (IQR, 5.27-8.00 cm). Of the 53 patients, 25 (47.2%) could be treated with a straight tube graft with a ≤20% diameter mismatch between the proximal and distal LZs. CONCLUSIONS: Almost 80% of the patients with TAAD had had a proximal LZ of ≥1.0 cm. Of these patients, 47.2% had anatomy amenable for endovascular therapy with a nontapered straight tube graft using commercially available devices. To increase patient eligibility for TAAD endovascular intervention, enhanced precision deployment with an adequate seal in shorter LZs will be required. Our results can serve as a guide for endovascular device specifications designed to treat this devastating condition.

Computational Investigation and Histopathological Validation of Interaction Between Stent Graft and Aorta in Retrograde Type A Dissection After TEVAR in Canine Models.

PURPOSE: Retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) has been a major drawback of endovascular treatment. To our knowledge, no studies have simulated and validated aortic injuries caused by stent grafts (SGs) in animal models. Therefore, the aim of this study was to evaluate and quantify the SG-aorta interaction through computational simulations and to investigate the underlying mechanism through histopathological examinations. METHODS: Two custom-made Fabulous® (DiNovA Meditech, Hang Zhou, China) SGs were implanted in 2 canine aortas with a 5-mm difference in the distance in landing locations. The aortic geometries were extracted from RTAD and non-RTAD cases. A computational SG model was assembled based on the implanted SG using the software Pro-ENGINEER Wildfire 5.0 (PTC Corporation, Needham, Mass). TEVAR simulations were performed 7 times for each canine model using Abaqus software (Providence, RI, USA), and the maximum aortic stress (MAS) was calculated and compared among the groups. Three months after SG implantation, the canine aortas were harvested, and were examined using hematoxylin and eosin staining and Elastica Van Gieson (EVG) staining to evaluate histopathological changes. RESULTS: In the computational models for both canines, MAS was observed at the proximal bare stent (PBS) at aortic greater curve. The PBS generated higher stress toward the aortic wall than other SG parts did. Moreover, the MAS was significantly higher in canine No.1 than in canine No.2 (0.415±0.210 versus 0.200±0.160 MPa) (p<0.01). Notably, in canine No.1, an RTAD developed at the MAS segment, and histopathological examinations of the segment showed an intimal flap, a false lumen, elastin changes, and medial necrosis. RTAD was not observed in canine No.2. In both SG-covered aortas, medial necrosis, elastic fiber stretching, and inflammatory infiltration were seen. CONCLUSION: The characteristic MAS distribution remained at the location where the apex of the PBS interacted with the aortic wall at greater curve. RTAD histopathological examinations showed intimal damage and medial necrosis at the proximal landing zone, at the same MAS location in computational simulations. The in vivo results were consistent with the computational simulations, suggesting the MAS at greater curve may cause RTAD, and the potential application of computational simulation in the mechanism study of RTAD.

Editor's Choice - Extending Aortic Replacement Beyond the Proximal Arch in Acute Type A Aortic Dissection: A Meta-Analysis of Short Term Outcomes and Long Term Actuarial Survival.

OBJECTIVE: The extent of aortic replacement during surgery for acute type A aortic dissection (ATAAD) is an important matter of debate. This meta-analysis aimed to evaluate the short and long term outcomes of a proximal aortic repair (PAR) vs. total arch replacement (TAR) in the treatment of ATAAD. DATA SOURCES: A systematic search of PubMed and Embase was performed. Studies comparing PAR to TAR for ATAAD were included. REVIEW METHODS: The primary outcomes were early death and long term actuarial survival at one, five, and 10 years. Random effects models in conjunction with relative risks (RRs) were used for meta-analyses. RESULTS: Nineteen studies were included, comprising 5 744 patients (proximal: n = 4 208; total arch: n = 1 536). PAR was associated with reduced early mortality (10.8% [95% confidence interval (CI) 8.4 - 13.7] vs. 14.0% [95% CI 10.4 - 18.7]; RR 0.73 [95% CI 0.63 - 0.85]) and reduced post-operative renal failure (10.4% [95% CI 7.2 - 14.8] vs. 11.1% [95% CI 6.7 - 17.5]; RR 0.77 [95% CI 0.66 - 0.90]), but there was no difference in stroke (8.0% [95% CI 5.9 - 10.7] vs. 7.3% [95% CI 4.6 - 11.3]; RR 0.87 [95% CI 0.69 - 1.10]). No statistically significant difference was found for survival after one year (83.2% [95% CI 77.5 - 87.7] vs. 78.6% [95% CI 69.7 - 85.5]; RR 1.05 [95% CI 0.99 - 1.11]), which persisted after five years (75.4% [95% CI 71.2 - 79.2] vs. 74.5% [95% CI 64.7 - 82.3]; RR 1.02 [95% CI 0.91 - 1.14]). After 10 years, there was a significant survival benefit for patients who underwent TAR (64.7% [95% CI 61.1 - 68.1] vs. 72.4% [95% CI 67.5 - 76.7]; RR 0.91 [95% CI 0.84 - 0.99]). CONCLUSION: PAR appears to lead to an improved early mortality rate and a reduced complication rate. In the current meta-analysis, the suggestion of an improved 10 year survival benefit of TAR was found, which should be interpreted in the context of potential confounders such as age at presentation, comorbidities, and haemodynamic stability. In any case, PAR seems to be intuitive in older patients with limited dissections, and in those presenting in less stable conditions.

Effectiveness of Proximal Landing Zones 0, 1, and 2 Hybrid Thoracic Endovascular Aortic Repair: A Single Centre 12 Year Experience.

OBJECTIVE: Hybrid thoracic endovascular aortic repair (TEVAR) is being accepted increasingly as a first line treatment for arch repair at the present authors' institution. This study aimed to clarify the effectiveness of zones 0, 1, and 2 landing hybrid TEVAR. METHODS: This was a retrospective single centre case series. From April 2008 to March 2020, 348 patients (median age 72 years; interquartile range [IQR] 65, 77 years) were enrolled, with a median follow up period of 5.6 years (IQR 2.6, 8.7 years). The procedures included zone 0 in 135 patients (38.8%), zone 1 in 82 patients (23.6%), and zone 2 proximal landing zone (LZ) hybrid TEVAR in 131 patients (37.6%). The pathologies consisted of dissecting aortic aneurysms in 123 (35.3%) patients. Emergency procedures were performed in 39 (11.2%) patients. RESULTS: The 30 day mortality (n = 2, 0.6%) and hospital deaths (n = 6, 1.7%) were registered. The stroke rate was 1.1% (n = 4), while early and late endoleak rates were 4.8% (n = 17) and 1.7% (n = 6), respectively. Type 1a endoleak and retrograde type A dissection occurred in seven (2.0%) and three (0.9%) patients, respectively. The cumulative survival, freedom from aorta related deaths, and freedom from aortic events in 10 years were 75.0%, 97.2%, and 84.1%, respectively. The freedom from aortic events in each landing zone in 10 years was 82.3%, 81.4%, and 87.9% for zones 0, 1, and 2, respectively. The 10 year survival rates were 82.5% and 73.6%; the 10 year aorta related death free rates were 94.9% and 98.6%, and the 10 year aortic event free rates were 82.3% and 85.5% in the zone 0 and zone 1 and 2 TEVAR, respectively. CONCLUSION: Satisfactory early and long term results of hybrid arch repair at zones 0, 1, and 2 were achieved. To avoid complications and aortic events, the treatment strategy of hybrid arch repair for aortic arch pathologies should be tailored using accurate pre-operative assessment of the ascending aorta and the aortic arch.

Hybrid type II and frozen elephant trunk in acute Stanford type A aortic dissections.

Objectives. Composite frozen elephant trunk is an increasingly popular solution for complex aortic pathologies. This review aims to compare outcomes of zone 0 type II hybrid (hybrid II) with the composite frozen elephant trunk (FET) technique in managing acute Stanford type A aortic dissections. Methods. PubMed and Embase were systematically searched using PRISMA protocol. 11 relevant studies describing the outcomes of hybrid II arch repair and FET techniques in patients with type A aortic dissection were included in the meta-analysis. The study focused on early post-operative 30-day outcomes analysing mortality, stroke, spinal cord injury, renal impairment requiring dialysis, bleeding and lung infection. Results. 1305 patients were included in the analysis - 343 receiving hybrid II repair and 962 treated with the FET. Meta-analysis of proportions showed Hybrid II was associated with less early mortality [5.0 (CI 3.1-7.8) vs 8.1 (CI 6.5-10.0) %], stroke [2.3 (CI 1.1-4.6) vs 7.0 (CI 5.5-8.8) %], spinal cord injury [2.0 (CI 0.9-4.3) vs 3.8 (CI 2.8-5.3) %], renal impairment requiring dialysis [7.9 (CI 5.5-11.2) vs 11.8 (CI 9.8-14.0) %], reoperation for bleeding [3.9 (CI 1.8-8.4) vs 10.6 (CI 8.1-13.8) %] and lung infection [14.8 (CI 10.8-20.0) vs 20.7 (CI 16.9-25.1) %]. Conclusion. Hybrid II should be considered in favour of FET technique in acute Stanford type A dissection patients who are at higher risk due to age and comorbidities.

Managing iatrogenic aortic dissection during primary percutaneous coronary intervention of the left main stem.

Iatrogenic aortic dissection post primary percutaneous coronary intervention (PCI) is rare but yet a serious complication. In this report, we present a case of a 40-year-old lady who had an aortic dissection post PCI which was initially missed by the conventional contrast images and required a gated computerized tomography aortogram to confirm the diagnosis. The patient was managed with strict blood pressure control resulting in complete healing of the dissection after 72 hours of the management. The case illustrates the importance of selecting the correct imaging to make an accurate diagnosis when aortic dissection is suspected and outlines the importance of blood pressure control in treating iatrogenic aortic dissections.

Emergent Triple-Branched TEVAR and Redistribution of the Branches to the Supra-Aortic Target Vessels for Treatment of a Contained Ruptured Descending Aortic Aneurysm Associated With a Chronic Type A Aortic Dissection.

PURPOSE: To demonstrate the feasibility of urgent endovascular treatment of a chronic type A dissection and contained rupture of the false lumen using a noncustomized triple-branched arch endograft, which necessitated reassignment of the branches to the supra-aortic vessels. CASE REPORT:: A 57-year-old patient with a contained rupture of the descending thoracic aorta, in the setting of a chronic type A dissection and a maximum aortic diameter of 85 mm, was converted to endovascular repair after failure of an open surgical approach. A custom-made triple-branched arch endograft designed for another patient was employed, with concomitant occlusion of the false lumen using a Candy Plug occluder. To adjust the graft's configuration to the patient's anatomy, the supra-aortic vessels were not assigned to the originally planned branches. The 12-month follow-up angiography demonstrated a satisfactory result. CONCLUSION: A noncustomized triple-branched arch endograft can be used in an emergency setting to treat chronic type A dissection, reassigning the branches to the supra-aortic vessels as needed.

Mesenteric Malperfusion Syndromes in Type A Aortic Dissection: Current Management Strategies.

Acute type A aortic dissection is a surgical emergency associated with high mortality and morbidity. When complicated with mesenteric malperfusion, its management carries a very high mortality. Many innovations in the field of vascular and cardiothoracic surgery in the last two decades have been tried in the continuous efforts to improve on the surgical outcomes. Although some reports have documented better mortality rates with reperfusion-first strategies, there is still room for improvement in the absence of a general consensus on its management.

Treatment of type A dissection: Searching for the Holy Grail.

Current principles of surgical treatment of type A dissections are for the most part based on best evidence practice for the lack of controlled randomized studies providing definitive scientific evidence. Despite its widespread use, axillary cannulation still remains a debated topic as the preferred method of cannulation and perfusion strategy in the treatment of this complex condition.

Acute type A dissection, coarctation of aorta, and levoatriocardinal vein-A rare combination.

Concomitant presence of acute type A dissection, coarctation of aorta and levoatriocardinal vein has not been described. We here present a case of aortic anuerysm complicated by type A dissection with coarctation of aorta and levoatriocardinal vein.

Management of malperfusion: New York approach and outcomes.

BACKGROUND AND AIM: Aortic branch malperfusion complicates up to one-third of acute type A aortic dissection (ATAAD), and it is a strong predictor of poor outcomes. We analyzed our results for the surgical management of this high-risk cohort. METHODS: We queried our aortic database for consecutive patients undergoing ATAAD repair. Those presenting with malperfusion were compared with those without. Outcomes were compared using univariate and multivariate analysis. RESULTS: From 1997 to 2019, a total of 336 patients underwent ATAAD repair. A total of 97 ATAAD patients presented with malperfusion. Malperfusion patients were more likely to be male (54.8% vs. 75.3%; p = .001), have had a prior myocardial infarction (11.9% vs. 26.8%; p = .001), to present with preoperative renal dysfunction (22.2% vs. 54.6%; p < .001), and to present with shock (12.6% vs. 28.9%; p = .001). The malperfusion group more often underwent coronary artery bypass grafting (5.4% vs. 24.7%; p < .001), and required additional noncardiac procedures 10.3% of the time. Operative mortality (0.8% vs. 15.5%; p < .001) and major adverse events (MAEs) (7.6% vs. 20.6%; p = .001) were both greater for the malperfusion patients. Ejection fraction, diabetes, and malperfusion were predictors of MAEs. Cerebral, coronary, mesenteric, and multiple vascular bed malperfusion were predictors of MAEs, while extremity, renal, and spinal were not. CONCLUSION: Improving outcomes for this high-risk cohort requires rapid diagnosis and reversal of ischemia while minimizing the risk of aortic rupture, irrespective of the strategic approach.

Endovascular ascending aortic repair in type A dissection: A systematic review.

PURPOSE: Up to 10% of acute type A aortic dissection (TAAD) patients are deemed unfit for open surgical repair, exposing these patients to high mortality rates. In recent years, thoracic endovascular aortic repair has proven to be a promising alternative treatment modality in specific cases. This study presents a comprehensive overview of the current state of catheter-based interventions in the setting of primary TAAD. METHODS: A literature search was conducted, using MEDLINE and PubMed databases according to PRISMA guidelines, updated until January 2020. Articles were selected if they reported on the endovascular repair of DeBakey Type I and II aortic dissections. The exclusion criteria were retrograde type A dissection, hybrid procedures, and combined outcome reporting of mixed aortic pathologies (e.g., pseudoaneurysm and intramural hematoma). RESULTS: A total of 31 articles, out of which 19 were case reports and 12 case series, describing a total of 92 patients, were included. The median follow-up was 6 months for case reports and the average follow-up was 14 months for case series. Overall technical success was 95.6% and 30-day mortality of 9%. Stroke and early endoleak rates were 6% and 18%, respectively. Reintervention was required in 14 patients (15%). CONCLUSION: This review not only demonstrates that endovascular repair in the setting of isolated TAAD is feasible with acceptable outcomes at short-term follow-up, but also underlines a lack of mid-late outcomes and reporting consistency. Studies with longer follow-up and careful consideration of patient selection are required before endovascular interventions can be widely introduced.

Deep Hypothermic Circulatory Arrest for Emergency Repair of Type A Aortic Dissection in a Patient with Cold Agglutinins.

Cold agglutinins (CA) are auto-antibodies that adhere to erythrocytes in cold temperatures, and can result in agglutination of red blood cells. This process can cause complement-mediated intravascular hemolysis, which can be catastrophic. We describe a patient who developed CA during initiation of deep hypothermic circulatory arrest for emergent repair of Type A aortic dissection. The patient was found to have anti-I and anti-C antibodies and a positive direct Coombs test. CA resolved with re-warming, and resulted in no adverse events.

Pre-emptive thoracic endovascular aortic repair is unnecessary in extended type A (DeBakey type I) aortic dissections.

OBJECTIVE: Pre-emptive thoracic endovascular aortic repair (TEVAR) improves late survival and limits progression of disease after type B aortic dissection, but the potential value of pre-emptive TEVAR has not been evaluated after type A dissection extending beyond the aortic arch (DeBakey type I). The purpose of this study was to compare disease progression and need for aortic intervention in survivors of acute, extended type A (ExTA) dissections after initial repair of the ascending aorta versus acute type B aortic dissections. METHODS: Consecutive patients presenting with ExTA or type B dissections between 2011 and 2018 were studied. Forty-three patients with ExTA and 44 with type B dissections who survived to discharge and had follow-up imaging studies were included in the analysis. Study end points included progression of aortic disease (>5 mm growth or extension), need for intervention, and death. RESULTS: The groups were not different for age, sex, atherosclerotic risk factors, or extent of dissection distal to the left subclavian artery. Following emergent ascending aortic repair, five ExTA patients (12%) underwent TEVAR within 4 months after discharge. Despite optimal medical treatment, 29 type B patients (66%) underwent early or late TEVAR (P < .001). During a mean follow-up of 38 ± 30 months, 38 ExTA patients (88%) did not require intervention-23 (53%) of whom showed no disease progression. In comparison, during a mean follow-up of 18 ± 6 months, 14 type B patients (32%) did not require intervention-nine (20%) of whom showed no disease progression (P = .003). There was one aortic-related late death in the ExTA group and two in the type B group. Compared with ExTA patients, type B patients had significantly worse intervention-free survival and intervention/growth-free survival (log rank, P < .001). CONCLUSIONS: In contrast with type B dissections, these midterm results demonstrate that one-half of ExTA aortic dissections show no disease progression in the thoracic or abdominal aorta, and few require additional interventions. After initial repair of the ascending aorta, pre-emptive TEVAR does not seem to be justified in patients with acute, ExTA dissections.

Long-term Results of Thoracic Endovascular Aortic Repair for Type B Aortic Dissection and Risk Factors for Survival.

Purpose: To compare characteristics of acute, subacute, and chronic type B aortic dissection and their influence on long-term results of thoracic endovascular aortic repair (TEVAR). Materials and Methods: In a single-center, retrospective cohort study, 314 patients (median age 52 years; 244 men) with acute (n=165), subacute (n=115), or chronic (n=34) type B aortic dissection underwent TEVAR between January 2009 and December 2013. Patient demographics, risk factors, and imaging characteristics were compared among the groups. Univariable and multivariable Cox regression analyses were performed to identify any factors influencing survival. Results: The acute and subacute patients exhibited more complications at presentation than chronic patients. However, the chronic patients exhibited more aneurysmal dilatation (p<0.001) and true lumen collapse (p<0.001). Over a mean follow-up of 68.1±22.9 months (range 2-108), subacute patients showed a lower reintervention rate (3.6% vs 12.1% vs 12.1%, p=0.045), a lower major complication rate (14.4% vs 33.1% vs 27.3%, p=0.002), and better cumulative overall survival (p=0.03) than the acute and chronic groups, respectively. Furthermore, acute patients developed more stent-graft-induced distal erosion (p=0.017) and retrograde type A dissection (RTAD) (p=0.036), whereas chronic patients had less aortic remodeling in the stented segment (p<0.001), distal thoracic aorta (p<0.001), and abdominal aorta (p=0.047). Finally, multivariable analysis demonstrated age >52 years, visceral malperfusion, and RTAD as independent factors influencing overall survival; aneurysmal dilatation, rupture/impending rupture, and RTAD were independent factors influencing aorta-specific survival. Conclusion: Acute and subacute patients had increased risks of rupture and complications at presentation, whereas chronic patients had increased risks for aneurysmal dilatation. From a long-term perspective, the subacute phase might be an optimal time for TEVAR in cases of type B aortic dissection that do not need emergent interventions. The risk factors influencing survival should be identified, carefully managed, and possibly prevented.

Salvage extracorporeal membrane oxygenation for acute type A aortic dissection with coronary malperfusion.

Perioperative use of extracorporeal membrane oxygenation (ECMO) in type A aortic dissection is a topic of contention with limited available data. We report the case of a patient presenting in severe cardiogenic shock due to coronary malperfusion and severe aortic insufficiency who was resucitated with ECMO as a bridge to recovery.