Retrograde ascending aortic dissection as an early complication of thoracic endovascular aortic repair.

Retrograde ascending aortic dissection (rAAD) is a potential complication of thoracic endovascular aortic repair (TEVAR), yet little data exist regarding its occurrence. This study examines the incidence, etiology, and outcome of this event. A prospective institutional database was used to identify cases of acute rAAD following TEVAR from a cohort of 309 consecutive procedures from March 2005 (date of initial Food and Drug Administration approval) to September 2010. The database was analyzed for the complication of rAAD as well as relevant patient and operative variables. The incidence of rAAD was 1.9% (6/309); all cases occurred with proximal landing zone in the ascending aorta and/or arch (zones 0-2). All were identified in the perioperative period (range, 0-6 days) with 33% (2/6) 30-day/in-hospital mortality. Eighty-three percent (5/6) underwent emergent repair; one patient died without repair. rAAD patients were similar to the non-rAAD group (n = 303) across pertinent variables, including age, gender, race, and device size (all P > .1). rAAD incidence by aortic pathology was 1.0% (2/200) for aneurysm, 4.4% (4/91) for dissection, and 0% (0/18) for transection; P = .08. rAAD incidence by device was TAG (Gore) 1.0% (2/205), Talent (Medtronic) 4.7% (2/43), and Zenith TX2 (Cook) 3.6% (2/55). rAAD incidence was observed to be higher among patients with an ascending aortic diameter ≥ 4.0 cm (4.8% vs 0.9% for ascending diameter <4.0 cm); P = .047. Incidence was also higher with proximal landing zone in the native ascending aorta (zone 0) 6.9% (2/29) versus 1.4% for all others (4/280); P = .101. For patients with dissection pathology and an ascending aortic diameter ≥ 4.0 cm, 11% (3/28) suffered rAAD; with the combination of native ascending aorta (zone 0) landing zone measuring ≥ 4.0 cm, the incidence was 25% (2/8). Definitive diagnosis was by computed tomography angiography (n = 1), intraoperative transesophageal echocardiography (n = 3), intraoperative arteriography (n = 1), or postmortem autopsy (n = 1). rAAD is a lethal early complication of TEVAR, which may be more common when treating dissection, with devices utilizing proximal bare springs or barbs for fixation, with native zone 0 proximal landing zone and with ascending aortic diameter ≥ 4 cm. Combinations of these risk factors may be particularly high risk. Intraoperative imaging assessment of the ascending aorta should be conducted following TEVAR to avoid under-recognition. National database reporting of this complication is needed to ensure safety and proper application of emerging TEVAR technology.

Williams JB ，Andersen ND ，Bhattacharya SD ，Scheer E ，Piccini JP ，McCann RL ，Hughes GC ... -  《-》

Repair of retrograde ascending dissection after descending stent grafting.

Retrograde dissection is now recognized as an important complication after thoracic endovascular aortic repair (TEVAR), but its treatment is poorly understood. Our objectives were to investigate the risks, describe the repair methods, and assess the outcomes of this complication. From 2000 to 2012, 766 patients underwent TEVAR. Of these patients, 14 (1.8%), plus 1 who had undergone TEVAR elsewhere (n = 15), developed retrograde dissection after stent grafting. They had undergone TEVAR for distal aortic dissection in 7, intramural hematoma in 5, aneurysm in 2, and transection in 1. Their mean age was 65 ± 9 years. At the initial TEVAR, the left subclavian artery was covered in 9, the mean stent graft diameter was 34 ± 2 mm, and >1 device was used in 8 patients. The site of entry tear was at the greater curvature in 11 and lesser curvature in 4. One patient ruptured and died 12 days after TEVAR and never made it to the operating room. The other 14 underwent proximal aortic repair. The median interval between TEVAR and repair of retrograde dissection was 6 months; 3 patients presented within 1 month. The repair techniques included reverse frozen elephant trunk in 5, total arch repair in 4, ascending or hemiarch repair in 4, and ascending TEVAR in 1. Concomitant procedures included aortic valve repair in 4, replacement in 2, root remodeling in 1, and coronary bypass in 1. No operative mortality occurred. One patient underwent reoperation for bleeding. Two required a tracheostomy for respiratory failure. However, no renal failure, stroke, or spinal injury occurred. At a median follow-up of 26 months, 4 aortic reoperations had occurred: 1 distal stent graft extension for type 1b endoleak, 2 hybrid thoracoabdominal completion repairs for growth of residual distal disease, and 1 emergency TEVAR for aortobronchial fistula. The latter patient died of septic complications, and 3 other late noncardiac deaths occurred. Retrograde ascending dissection can present as an early or a late complication after descending stent grafting because of aortic instability or disease progression and has usually been associated with descending dissection or intramural hematoma. It is a life-threatening complication that can be managed safely with early recognition and rapid delivery of open or hybrid repair.

Idrees J ，Arafat A ，Johnston DR ，Svensson LG ，Roselli EE ... -  《-》

Impact of proximal seal zone length and intramural hematoma on clinical outcomes and aortic remodeling after thoracic endovascular aortic repair for aortic dissections.

Thoracic endovascular aortic repair (TEVAR) has become standard treatment of complicated type B aortic dissections (TBADs). Whereas adequate proximal seal is a fundamental requisite for TEVAR, what constitutes "adequate" in dissections and its impact on outcomes remain unclear. The goal of this study was to describe the proximal seal zone achieved with associated clinical outcomes and aortic remodeling. A retrospective review was performed of TEVARs for TBAD at a single institution from 2006 to 2016. Three-dimensional centerline analysis of preoperative computed tomography was used to identify the primary entry tear, dissection extent, distances between arch branches, and intramural hematoma (IMH) involvement of the proximal seal zone. Patients were categorized into group A, those with proximal extent of seal zone in IMH/dissection-free aorta, and group B, those with landing zone entirely within IMH. Clinical outcomes including retrograde type A dissection (RTAD), death, and aortic reinterventions were recorded. Postoperative computed tomography scans were analyzed for remodeling of the true and false lumen volumes of the thoracic aorta. Seventy-one patients who underwent TEVAR for TBAD were reviewed. Indications for TEVAR included malperfusion, aneurysm, persistent pain, rupture, uncontrolled hypertension, and other. Mean follow-up was 14 months. In 26 (37%) patients, the proximal extent of the seal zone was without IMH, whereas 45 (63%) patients had proximal seal zone entirely in IMH. Proximal seal zone of 2-cm IMH-free aorta was achieved in only six (8.5%) patients. Review of arch anatomy revealed that to create a 2-cm landing zone of IMH-free aorta, 31 (43.7%) patients would have required coverage of all three arch branch vessels. Postoperatively, two patients developed image-proven RTADs requiring open repair, and one patient had sudden death. All three of these patients had TEVAR with the proximal seal zone entirely in IMH. No RTADs occurred in patients whose proximal seal zone involved healthy aortic segment. At 24 months, overall survival was 93% and freedom from aorta-related mortality was 97.4%. Complete thoracic false lumen thrombosis was seen in 46% of patients. Aortic remodeling, such as true lumen expansion, false lumen regression, and false lumen thrombosis, was similar in both groups of patients. Whereas achieving 2 cm of IMH-free proximal seal zone during TEVAR for TBAD would often require extensive arch branch coverage, failure to achieve any IMH-free proximal seal zone may be associated with higher incidence of RTAD. The length and quality of the proximal seal zone did not affect the subsequent aortic remodeling after TEVAR.

Kuo EC ，Veranyan N ，Johnson CE ，Weaver FA ，Ham SW ，Rowe VL ，Fleischman F ，Bowdish M ，Han SM ... -  《-》

Zone zero thoracic endovascular aortic repair: A proposed modification to the classification of landing zones.

Endovascular stent-grafting provides an alternative treatment option for high-risk patients with ascending aortic disease. The feasibility of this approach has been demonstrated before. We assess the updated experience with ascending thoracic endovascular aortic repair and propose a modification of the landing zone classification based on the outcomes. From 2006 to 2016, 39 patients deemed very high risk for open replacement underwent endovascular repair of ascending aorta for acute type A dissection (12, 31%), intramural hematoma (2, 5%), pseudoaneurysm (22, 56%), and chronic dissection suture line entry tear (3, 8%). Ascending thoracic endovascular aortic repair was performed in 36 patients. In 3 patients with pseudoaneurysm, occluder devices were used. Computed tomography imaging analysis was performed, and the extent of aortic pathology was designated by segmental proximity to the left ventricle. Segmental anatomy of the proximal aorta was designed as zone 0A from the annulus to the distal margin of highest coronary, 0B extends from above the coronary to the distal margin of right pulmonary artery, and 0C extends from the right pulmonary artery border to the innominate artery. Multivariable time to event Cox regression analysis was performed to predict mortality, and long-term survival was estimated using the Kaplan-Meier method. Operative mortality was 13%; all 5 deaths occurred after emergency ascending thoracic endovascular aortic repair for type A dissection. Other complications included stroke in 4 patients (10%), myocardial infarction in 2 patients (5%), tracheostomy in 2 patients (5%), and dialysis in 2 patients (5%). In patients with acute type A dissection, the ascending pathology extended into zone 0A in 10 (71%) and 0B in 4 (29%). Among those with pseudoaneurysm, the location of the defect was in 0B in 11 (50%), 0C in 10 (45%), and 0A in 1. Among the patients with chronic dissection, the defect was located in 0C in all 3 (100%). After multivariable adjustment, Cox regression predicted significantly higher hazard of mortality with disease involving zone 0A versus 0C (P = .020) and older age (P = .026). Kaplan-Meier estimate of survival was also significantly worse in patients with disease extension into 0A versus 0C (P = .0018). At 30 days, 1 year, and 5 years, the overall survival was 81%, 74%, and 64% and freedom from reintervention was 85%, 77%, and 68%, respectively. The modified zone zero classification is useful for characterizing extent of ascending aortic pathology and assessing prognosis. Location of the defect varies by pathology, and the presence of 0A disease predicts worse outcomes. Design of endovascular devices should be tailored to the aortic pathology and zone characteristics.

Roselli EE ，Idrees JJ ，Johnston DR ，Eagleton MJ ，Desai MY ，Svensson LG ... -  《-》

Determining the Optimal Proximal Landing Zone for TEVAR in the Aortic Arch: Comparing the Occurrence of the Bird-Beak Phenomenon in Zone 0 vs Zones 1 and 2.

Kudo T ，Kuratani T ，Shimamura K ，Sawa Y ... -  《-》