Open repair of chronic thoracic and thoracoabdominal aortic dissection using deep hypothermia and circulatory arrest

Deep Circulatory Arrest and Left Thoracotomy Approach Allow Open Repair of Chronic IIIb Dissection Associated to a Large Aortic Arch: A Case Series

Thoracic aortic aneurysms evolving within a type IIIb chronic aortic dissection are mostly treated with the deployment of an endograft. However, several cases of dissecting aneurysms are associated with a significant dilatation of the aortic arch. These cases are usually managed in 2 steps: arch reconstruction or supra-aortic trunk debranching at first and a secondary graft deployment for the descending thoracic aorta. We present through this case series an alternative approach for this severe condition which consists in the replacement of the thoracic aorta from its hemi-arch to the distal thoracic or visceral aorta using a left thoracotomy. We deliberately neglected the remaining dissecting aorta if its diameter was below 45 mm, hypothesizing its nonevolution after repair. From 2012 to 2021, 9 patients have been treated for a thoracic aneurysm evolving after a IIIb chronic aortic dissection using a left thoracotomy and a 19°C circulatory arrest. Immediate postoperative results show no mortality or neurological disorders, and the 7 years follow-up for all of these 9 cases enlightened the absence of aneurysmal evolution especially for the distal anastomosis and the remaining dissected aorta. This work suggests that this direct approach strategy can definitively treat a thoracic dissecting aneurysm unsuitable for a simple endovascular treatment.

Antegrade cerebral perfusion via the right subclavian artery during open distal arch or proximal descending aortic repair from left thoracotomy

In the current endovascular era, open surgery through left posterolateral thoracotomy with moderate to deep hypothermic circulatory arrest remains an alternative for treating chronic distal arch or proximal descending aortic diseases, allowing cardiovascular surgeons to definitively repair the aorta in a single stage. When utilizing this approach, this report illustrates an alternative surgical technique for antegrade body perfusion during cooling, antegrade selective cerebral perfusion and rewarming, through a prosthetic graft on the right subclavian artery. This report shows the safety and feasibility of this technique during open distal arch and/or proximal descending aortic surgery through left posterolateral thoracotomy, after shifting the patient from a supine to the right lateral decubitus position.

Comparison of open thoracoabdominal repair for chronic aortic dissections and aneurysms

OBJECTIVE

Aortic dissection is common in patients undergoing open surgical repair of thoracoabdominal aortic aneurysms (TAAAs). Most often, dissection is chronic and is associated with progressive aortic dilatation. Because contemporary outcomes in chronic dissection are not clearly understood, we compared patient characteristics and outcomes after open TAAA repair between patients with chronic dissection and those with non-dissection aneurysm.

METHODS

We retrospectively analyzed data from 3470 open TAAA repairs performed in a single practice. Operations were for non-dissection aneurysm in 2351 (67.8%) and chronic dissection in 1119 (32.2%). Outcomes included operative mortality and adverse events, a composite variable comprising operative death and persistent (present at discharge) stroke, paraplegia, paraparesis, and renal failure necessitating dialysis. Logistic regression identified predictors of operative mortality and adverse events. Time-to-event analyses examined survival, death, repair failure, subsequent progressive repair, and survival free of failure or subsequent repair.

RESULTS

Compared with patients with non-dissection aneurysm, those with chronic dissection were younger, had fewer atherosclerotic risk factors, and were more likely to have heritable thoracic aortic disease and undergo extent II repair. The operative mortality rate was 8.5% (n = 296) overall and was higher in non-dissection aneurysm patients (n = 217; 9.2%) than in chronic dissection patients (n = 79; 7.1%; P = .03). Adverse events were less frequent (P = .01) in patients with chronic dissection (n = 145; 13.0%), 22 (2.0%) of whom had persistent paraplegia. Chronic dissection was not predictive of operative mortality (P = .5) or adverse events (P = .6). Operative mortality and adverse events, respectively, were independently predicted by emergency repair (odds ratio [OR], 3.46 and 2.87), chronic kidney disease (OR, 1.74 and 1.81), extent II TAAA repair (OR, 1.44 and 1.73), increasing age (OR, 1.04/year and 1.04/year), and increasing aortic cross-clamp time (OR, 1.02/minutes and 1.02/minutes). Patients with chronic dissection had lower 10-year unadjusted mortality (42% vs 69%) but more frequent repair failure (5% vs 3%) and subsequent repair for progressive aortic disease (11% vs 5%) than patients with non-dissection aneurysm (P < .001); these differences were no longer statistically significant after adjustment.

CONCLUSIONS

Outcomes of open TAAA repair vary by aortic disease type. Emergency repairs and atherosclerotic diseases most commonly occur in patients with non-dissection aneurysm and independently predict operative mortality. Repair of chronic dissection is associated with low rates of adverse events, including operative mortality and persistent paraplegia, along with reasonable late survival and good durability. However, patients with chronic dissection tend to more commonly undergo subsequent repair to treat progressive aortic disease, which emphasizes the need for robust long-term imaging surveillance protocols.

Comparative Analysis of Endovascular Repair of Single-Branched Stent-Graft and Hybrid Procedure for Patients With Type B Acute Aortic Dissection Involving the Left Subclavian Artery

PURPOSE

Thoracic endovascular aortic repair (TEVAR) with left subclavian artery (LSA) revascularization has been used in patients with type B aortic dissection (TBAD), with inadequate proximal landing zone (PLZ). The outcomes of comparisons between TEVAR and hybrid procedure on patients with TBAD, with inadequate PLZ, are rarely reported. This study sought to compare and clarify the early and midterm outcomes between TEVAR and hybrid procedure in patients with TBAD, with inadequate PLZ.

MATERIALS AND METHODS

Between January 2019 and December 2021, 93 patients with TBAD, with inadequate PLZ, who underwent TEVAR or hybrid procedure, were retrospectively evaluated in Beijing Anzhen hospital. Demographics, comorbidities, preoperative imaging features, periprocedural details, and follow-up outcomes were analyzed. Survival was analyzed according to Kaplan-Meier method.

RESULTS

TEVAR procedures were performed on 41 patients (TEVAR group) and hybrid procedures on 52 patients (hybrid group). Early events, 30 day mortality, and all-cause mortality, were not significantly different between the 2 groups. However, patients receiving TEVAR had significantly shorter procedure time (p<0.001), hospital stay (p<0.001), and intensive care unit (ICU) stay (p=0.001) compared with those in the hybrid group. Patients receiving TEVAR had significantly lower midterm events (p=0.014) and re-intervention (p=0.015) compared with those in the hybrid group.

CONCLUSION

The study indicated that TEVAR with LSA revascularization for TBAD with inadequate PLZ is associated with a trend toward lower rates of midterm events, while the early and midterm mortalities were comparable with those in hybrid procedure.

CLINICAL IMPACT

This study is novel as it compared the outcomes between thoracic endovascular aortic repair (TEVAR) and hybrid procedure in patients with type B aortic dissection (TBAD), with inadequate proximal landing zone, which has been rarely reported previously. We believe that our study makes a significant contribution to the literature because it is clinically relevant as it demonstrated that TEVAR with left subclavian artery (LSA) revascularization for TBAD with inadequate proximal landing zone is associated with a trend toward lower rates of mid-term events, while the early and mid-term mortalities were comparable with those in the hybrid procedure.

Whole Body Retrograde Perfusion Combined With Central Aortic Perfusion Strategy in the Repair of Distal Arch Pathology Through a Lateral Thoracotomy

OBJECTIVE

To compare the results of the hypothermic circulatory arrest (HCA) + retrograde whole-body perfusion (RBP) technique with those of deep hypothermic circulatory arrest (DHCA-only) approach.

METHODS

Limited data are available on cerebral protection techniques when distal arch repairs are performed through a lateral thoracotomy. In 2012, the RBP technique was introduced as adjunct to HCA during open distal arch repair via thoracotomy. We reviewed the results of the HCA + RBP technique compared with those of the DHCA-only approach. From February 2000 to November 2019, 189 patients (median age, 59 [IQR, 46 to 71] years; 30.7% female) underwent open distal arch repair via lateral thoracotomy to treat aortic aneurysms. The DHCA technique was used in 117 patients (62%, median age 53 [IQR, 41 to 60] years), whereas HCA + RBP was used in 72 patients (38%, median age 65 [IQR, 51 to 74] years). In HCA + RBP patients, cardiopulmonary bypass was interrupted when systemic cooling achieved isoelectric electroencephalogram; once the distal arch had been opened, RBP was then initiated via the venous cannula (flow of 700 to 1000 mL/min, central venous pressure <15 to 20 mm Hg).

RESULTS

The stroke rate was significantly lower in the HCA + RBP group (3%, n=2) compared with the DHCA-only (12%, n=14) (P=.031), despite longer circulatory arrest times in HCA + RBP compared with the DHCA-only (31 [IQR, 25 to 40] minutes vs 22 [IQR, 17 to 30] minutes, respectively; P<.001). Operative mortality for patients undergoing HCA + RBP was 6.7% (n=4), whereas for those undergoing DHCA-only it was 10.4% (n=12) (P=.410). The 1-, 3-, and 5-year age-adjusted survival rates for the DHCA group are 86%, 81%, and 75%, respectively. The 1-, 3-, and 5-year age-adjusted survival rates for the HCA + RBP group are 88%, 88%, and 76%, respectively.

CONCLUSION

The addition of RBP to HCA in the treatment of distal open arch repair via a lateral thoracotomy is safe and provides excellent neurological protection.

Imaging and Surveillance of Chronic Aortic Dissection: A Scientific Statement From the American Heart Association

All patients surviving an acute aortic dissection require continued lifelong surveillance of their diseased aorta. Late complications, driven predominantly by chronic false lumen degeneration and aneurysm formation, often require surgical, endovascular, or hybrid interventions to treat or prevent aortic rupture. Imaging plays a central role in the medical decision-making of patients with chronic aortic dissection. Accurate aortic diameter measurements and rigorous, systematic documentation of diameter changes over time with different imaging equipment and modalities pose a range of practical challenges in these complex patients. Currently, no guidelines or recommendations for imaging surveillance in patients with chronic aortic dissection exist. In this document, we present state-of-the-art imaging and measurement techniques for patients with chronic aortic dissection and clarify the need for standardized measurements and reporting for lifelong surveillance. We also examine the emerging role of imaging and computer simulations to predict aortic false lumen degeneration, remodeling, and biomechanical failure from morphological and hemodynamic features. These insights may improve risk stratification, individualize contemporary treatment options, and potentially aid in the conception of novel treatment strategies in the future.

Transapical cannulation for surgical repair of chronic type B aortic dissection

Open surgery for chronic type B aortic dissection has been shown to have considerable risks of cerebrovascular complications. Because retrograde perfusion is a potential cause of intraoperative cerebrovascular events, we report our transapical cannulation strategy for descending aorta replacement in chronic type B aortic dissection repair with circulatory arrest. This technique provides an easy and quick establishment of cardiopulmonary bypass by way of a left thoracotomy, and prevention of cerebrovascular event. Transapical cannula can be also used as a vent to ensure a bloodless field during proximal anastomosis and to prevent extension of left ventricle during rewarming. Transapical cannulation is a useful option in open repair of the descending aorta for chronic type B aortic dissection by way of left thoracotomy.

Surgical Strategy for Chronic Type B Dissecting Aortic Aneurysm to Prevent Aorta-Related Events

BACKGROUND

This study was aimed to evaluate the outcomes of performing open repair or thoracic endovascular aortic repair for chronic type B dissecting aortic aneurysm.

METHODS

From July 2004 to February 2019, 52 patients underwent surgery as open repair (n = 32) or endovascular repair (n = 20) for chronic type B dissecting aortic aneurysm. Replacement of the aorta was limited to the aneurysmal portion with or without reconstructing the visceral arteries or the segmental arteries. Stent grafts were deployed in the true lumen above the celiac artery to cover the primary entry for even DeBakey IIIb dissection.

RESULTS

Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. Operative mortality and morbidity rates, including spinal cord ischemia incidence, did not differ between the groups. In the endovascular repair group, 3 patients died due to rupture of residual false lumen in the early, and late postoperative follow-up. The 5-year rate of freedom from all-cause death, aorta-related death, and aorta-related event were 84% ± 6%, 94% ± 3% and 84% ± 6%. The endovascular repair was independently associated with all-cause death (hazard ratio [HR], 5.7; confidence interval [CI], 1.02-31.6; P = 0.04) and aorta-related event (HR, 30.9; CI 4.9-195.0; P < 0.001). In the open group, postoperative residual aortic diameter was an independent predictor of aorta-related events, and the threshold was 41 mm.

CONCLUSIONS

Open repair remains a better option than simple endovascular repair alone in DeBakey IIIb dissection, but the distal un-resected aortic portion over 41 mm was associated with late aortic events.

Perioperative and long-term outcome after ascending aortic and arch repair with elephant trunk and open thoracoabdominal aortic aneurysm repair

OBJECTIVE

To describe the outcome of open thoracoabdominal aortic aneurysm (TAAA) repair following previous aortic arch repair including elephant trunk (ET) or frozen elephant trunk (FET) for acute and chronic pathologies.

METHODS

This was a retrospective, observational, multicenter study including 32 patients treated between 2006 and 2019 in two aortic centers using identical surgical protocols. Assessment focused on perioperative and long-term outcome, namely in-hospital morbidity and mortality, as well as procedure-related reintervention rate and aortic-related mortality rate. Kaplan-Meier curves with 95% confidence intervals were used to analyze the overall survival after surgery within the cohort.

RESULTS

Thirty-two patients (mean age, 45.0 ± 13.6 years; 20 males [62.5%]) were treated because of acute (34.38% [n = 11]) or chronic (65.62% [n = 21]) aortic pathologies, including residual dissection following acute, symptomatic type A dissection (n = 7) and symptomatic mega aortic syndrome (n = 4), as well as post-dissection TAAA (n = 18) and asymptomatic mega aortic syndrome (n = 3). Twenty-eight patients (87.5%) received type II repair, and 4 patients (12.5%) received type III repair after previous ascending aorta and arch repair including ET/FET. Concomitant infrarenal and iliac vessel repair was performed in 38.7% (n = 12) and 29.4% (n = 10), respectively. The in-hospital mortality rate was 18.75% (n = 6). Spinal cord ischemia occurred in two cases, both after one-stage emergency procedure with one case of permanent paraplegia. Temporary acute kidney injury occurred in 41.94% (n = 13). The estimated 1-year survival rate was 78.1% (95% confidence interval, 63.9%-95.6%), with a median follow-up time of 1.29 years (interquartile range, 0.26-3.88 years). No procedure-related reinterventions and one case of aortic-related mortality, namely sepsis because of graft infection, was observed.

CONCLUSIONS

Open TAAA repair following aortic arch repair including ET or FET because of acute or chronic aortic pathologies is associated with a relevant perioperative morbidity and mortality rate. During follow-up, a low aortic-related mortality rate and procedure-related reintervention rate were observed.

Chronic type B aortic dissection complicated by repetitive spinal cord ischaemia

Chronic type B aortic dissection complicated by repetitive transient spinal cord ischaemia is rare. Reduced blood flow in the segmental arteries supplying the radicular arteries in the false lumen is the main cause of this pathology. Individual variations in spinal cord circulation are difficult to identify; therefore, the mechanisms of spinal cord ischaemia are poorly understood. We encountered a patient with chronic type B aortic dissection experiencing repetitive spinal cord ischaemia that finally led to spinal cord infarction. The patient recovered, except for mild monoparesis of the right leg. With the growth of the dissected aorta, we planned for surgical treatment to restore the blood supply in the spinal cord. The patient underwent thoraco-abdominal aortic repair using deep hypothermia, and favourable neurological results were achieved.

Incidence of spinal cord ischemia according to the patency of reimplanted segmental arteries during thoracoabdominal aortic replacement

BACKGROUND

This study aimed to investigate the impact of segmental artery reimplantation and its patency on spinal cord ischemia (SCI) in thoracoabdominal aorta replacement.

METHODS

For 193 patients who underwent early postoperative computed tomographic (CT) angiography after thoracoabdominal aorta replacement, the technique of segmental artery reimplantation, their patency, and postoperative SCI were retrospectively investigated.

RESULTS

The early patency rate of reimplanted segmental artery was 83.3% (210 of 252), as 13 were taken down intraoperatively and 42 were not visualized in the postoperative CT angiography. The patency rate differed according to the reimplantation technique: 93.6% (131/140) for en bloc patch, 95.6% (43/45) for small individual patch, and 53.7% (36/67) for graft interposition. SCI occurred in 13 (6.3%) patients, 4 of whom (2.0%) remained paraplegic permanently. SCI was significantly more frequent (P=0.044) in the patients in whom segmental artery reimplantation was not successful (take-down or occlusion, 6/37=16.2%) than in those who had all segmental arteries sacrificed intentionally (2/64=3.1%) and those who showed patency of all reimplanted segmental arteries (5/92=5.4%). Especially, there was no permanent paraplegia in the last group. Failure of intended segmental artery reimplantation was a significant risk factor of postoperative SCI in logistic regression analysis (P=0.012; odds ratio 4.65, 95% confidence interval 1.41-15.36).

CONCLUSIONS

During thoracoabdominal aorta replacement, attention should be paid to the segmental artery reimplantation technique, which affects the risk of occlusion or intraoperative takedown and thereby may have impact on postoperative SCI.

A 23-year experience with the reversed elephant trunk technique for staged repair of extensive thoracic aortic aneurysm

OBJECTIVE

The reversed elephant trunk technique permits staged repair of extensive thoracic aortic aneurysm in patients whose distal (ie, descending thoracic and thoracoabdominal) aorta is symptomatic or disproportionately large compared with their proximal aorta (ie, ascending aorta and transverse aortic arch). We present our 23-year experience with the reversed elephant trunk approach.

METHODS

Between 1994 and 2017, 94 patients (median age 62 [46-69] years) underwent stage 1 reversed elephant trunk repair of the distal aorta. Fifty-three patients (56%) had aortic dissection, and 31 patients (33%) had heritable thoracic aortic disease. Eighty-eight operations (94%) were Crawford extent I or II thoracoabdominal aortic repairs. Twenty-seven patients (29%) underwent subsequent stage 2 repair of the proximal aorta; 14 patients (52%) required redo median sternotomy. The median time between the stage 1 and 2 operations was 18.8 (4.8-69.3) months.

RESULTS

The operative mortality was 10% (9/94) for stage 1 repairs and 4% (1/27) for stage 2 repairs; 1 patient with heritable thoracic aortic disease died after stage 1 repair (1/31, 3%), and 1 patient died after stage 2 repair (1/13, 8%). Two patients (2%) had ruptures after stage 1 repair; 1 resulted in death, and 1 precipitated emergency stage 2 repair. In total, 36 patients (38%) who survived stage 1 repair died before stage 2 reversed elephant trunk completion repair could be performed.

CONCLUSIONS

Managing extensive aortic aneurysm with the 2-stage reversed elephant trunk technique yields acceptable short-term outcomes. This technique is useful for the reversed elephant trunk in patients who require distal aortic repair before proximal repair and is particularly effective in patients with heritable thoracic aortic disease. The low number of patients returning for completion repair is concerning. Rigorous surveillance is needed.

Staged total arch replacement, followed by fenestrated-branched endovascular aortic repair, for patients with mega aortic syndrome

OBJECTIVE

The aim of the present study was to review the clinical outcomes of a staged approach using total arch replacement (TAR) with an elephant trunk or a frozen elephant trunk, followed by fenestrated-branched endovascular aortic repair (F-BEVAR) for patients with mega aortic syndrome.

METHODS

We reviewed the clinical data and outcomes of 11 consecutive patients (8 men; mean age, 71 ± 7 years) treated by staged TAR and F-BEVAR from January 2014 to December 2018. The F-BEVAR procedures were performed under a prospective, nonrandomized, physician-sponsored investigational device exemption protocol. All patients had had mega aortic syndrome, defined by an ascending aorta, arch, and extent I-II thoracoabdominal aortic aneurysm. The endpoints were 30-day mortality, major adverse events (MAE), patient survival, freedom from reintervention, and freedom from target vessel instability.

RESULTS

Of the 11 patients, 6 had developed chronic postdissection aneurysms after previous Stanford A (three A₁₁, two A₁₀, one A₉) dissection repair and 5 had had degenerative aneurysms with no suitable landing zone in the aortic arch. The thoracoabdominal aortic aneurysms were classified as extent I in four patients and extent II in seven. One patient had died within 30 days after TAR (9.0%). However, none of the remaining 10 patients who had undergone F-BEVAR had died. First-stage TAR resulted in MAE in three patients (27%), including one spinal cord injury. The mean length of stay was 12 ± 6 days. The mean interval between TAR and F-BEVAR was 245 ± 138 days with no aneurysm rupture during the interval. Second-stage F-BEVAR was associated with MAE in two patients (20%), including spinal cord injury in one patient from spinal hematoma due to placement of a cerebrospinal fluid drain. The mean follow-up period was 14 ± 10 months. At 2 years postoperatively, patient survival, primary patency, secondary patency, and freedom from renal-mesenteric target vessel instability was 80% ± 9%, 94% ± 6%, 100%, and 86% ± 8%, respectively. No aortic-related deaths occurred during the follow-up period. Four patients had required reintervention, all performed using an endovascular approach.

CONCLUSIONS

A staged approach to treatment of mega aortic syndrome using TAR and F-BEVAR is a feasible alternative for selected high-risk patients. Larger clinical experience and longer follow-up are needed.

Clinical and Morphologic Outcomes of Endovascular Repair for Subacute and Chronic Type B Aortic Dissection

BACKGROUND

The objective of the study was to assess long-term remodeling, survival, and reintervention outcomes after thoracic endovascular aortic repair (TEVAR) for subacute and chronic type B aortic dissection (TBAD).

METHODS

All patients who underwent TEVAR for subacute or chronic TBAD at a tertiary referral center between 1999 and 2015 were included in this cohort study. The primary outcome was aortic remodeling, and secondary outcomes included survival, rate of major complications, and reinterventions.

RESULTS

Fifty patients were included, with mean age of 62.4 years, 10 (20%) DeBakey type IIIA and 40 (80%) DeBakey type IIIB dissection; 45 standard TEVAR, 2 branched TEVAR, 3 TEVAR combined with fenestrated or branched EVAR. Indication for TEVAR was intact (n = 40) or ruptured (n = 1) postdissection aneurysm, hypoperfusion (n = 4), treatment-refractory pain (n = 2), or a combination (n = 3). Mean clinical follow-up was 76 months, and median radiological follow-up was 46 months. Thirty-day survival was 96%, stroke 4%, renal failure 0%, paraplegia 0%. Three- and five-year survival was 92% (95% confidence interval (CI) [79; 97]) and 77% (95% CI [61; 87]), respectively. Of 19 late deaths, 6 were confirmed aorta related. Five-year freedom from reintervention was 69% (95% CI [53-80]). Distal stent graft extension due to aortic dilatation composed most reinterventions. Mean maximal aortic diameter was 58.7 mm preoperatively and 51.9 mm on last follow-up (P = 0.003). On thoracic level, true lumen expanded (+10.0 mm, 95% CI [6.4; 13.6]) (P < 0.001) and false lumen decreased (-11.9 mm, 95% CI [-15.2; -8.5]) (P < 0.001) from baseline to the last computed tomography. In the abdominal aorta, true lumen diameter change was +3.1 mm (95% CI [1.4; 4.8]) (P = 0.001); false lumen diameter change was +1.0 mm (95% CI [-1.8; 3.8]) (P = 0.464).

CONCLUSIONS

TEVAR for subacute and chronic TBAD results in favorable remodeling of the thoracic but not the abdominal aorta. Five-year survival is almost 80%, but late aortic deaths still occur. Aortic dilatation distal to the treated segment requiring reintervention is common, emphasizing the importance of follow-up.

Perioperative and long-term outcomes after thoracoabdominal aortic aneurysm repair of chronic dissection etiology

OBJECTIVE

Open repair of thoracoabdominal aortic aneurysms (TAAAs) that have developed secondary to chronic dissection (CD) is often more complex than repair of degenerative aneurysms (DAs). However, the literature is conflicted regarding the effect of CD on perioperative and long-term outcomes after open TAAA repair. The goal of this study was to determine whether CD predicts negative outcomes after TAAA repair.

METHODS

All open type I to type III TAAA repairs performed from 1987 to 2015 were evaluated using a single institutional database. End points included in-hospital death, spinal cord ischemia (SCI), major adverse events (MAEs), and long-term survival. Repairs performed for rupture or acute dissection were excluded. Univariate analysis was conducted using the Fisher's exact test for categorical variables and the Wilcoxon rank sum test for continuous variables. Logistic multivariable regression was used for the in-hospital end points, and survival analyses were performed with Cox proportional hazards modeling and Kaplan-Meier techniques.

RESULTS

During the study period, 453 patients underwent an intact open type I to type III TAAA repair. Ninety (20%) were performed for patients with CD. Those with CD were more likely to be younger (59 years vs 72 years; P < .001), to have an extent II lesion (30% vs 16%; P < .001), and to have Marfan syndrome (18% vs 0.6%; P < .001) and less likely to have coronary artery disease (28% vs 25%; P = .01) or chronic obstructive pulmonary disease (12% vs 27%; P = .004) compared with patients with DA. Twelve percent of patients with CD died perioperatively compared with 6% of those with DA (P = .03). Eighteen percent of CD patients suffered from SCI compared with 12% of DA patients (P = .2). Fifty-nine CD patients suffered a MAE compared with 42% of those with DA (P = .006). Multivariable analysis revealed CD to be an independent predictor of perioperative death (adjusted odds ratio [AOR], 3.1; 95% confidence interval [CI], 1.2-8.0; P = .02) with adjustment for age and Crawford extent. CD was also found to be independently predictive of any MAE (AOR, 2.5; 95% CI, 1.4-4.6; P = .002). CD was not associated with increased risk of SCI (AOR, 1.4; 95% CI, 0.6-3.2; P = .4). There was a long-term survival advantage in the CD cohort in the unadjusted analysis (log-rank, P = .009) but not in the adjusted analysis (CD adjusted hazard ratio, 0.9; 95% CI, 0.6-1.4; P = .7).

CONCLUSIONS

When analysis is limited to type I to type III TAAAs, open repair of patients with CD leads to increased perioperative mortality and morbidity compared with patients with DA. However, age-adjusted long-term survival is no different between the two cohorts.

Loeys-Dietz syndrome pathology and aspects of cardiovascular management: A systematic review

Loeys-Dietz syndrome is an autosomal dominant genetic disorder which is associated with significant and often crucial vascular manifestations. This review is aimed to examine current evidence on pathophysiology and management of Loeys-Dietz syndrome in current era. A comprehensive electronic search was done to identify the articles that discussed all the aspects of Loeys-Dietz syndrome, combined key words and Medical Subject Headings (MeSH) terms were used. Relevant articles have been summarized in each relevant section. Loeys-Dietz syndrome is an autosomal dominant genetic disorder which has combined and multi-systemic manifestations. The increased breakdown of extracellular matrix predisposes an individual to developing aneurysms in the aortic tree which is undoubtedly the most significant complication of this disorder. Understanding the pathophysiology and natural history of Loeys-Dietz syndrome and regular surveillance is important to plan prophylactic interventions to prevent life-threatening aortic emergencies which can be fatal. Loeys-Dietz syndrome is an aggressive genetic condition that predisposes an individual to the development of life-threatening aortic aneurysms. Our understanding of Loeys-Dietz syndrome remains ever-changing and it is likely that the knowledge regarding its diagnosis and treatment will become more clearly defined in the coming years with deeper genetic studies.

Fenestrated/Branched Endovascular Repair for Postdissection Thoracoabdominal Aneurysms: A Systematic Review with Pooled Data Analysis

PURPOSE

Patients who have survived an acute aortic dissection remain at risk for postdissection thoracoabdominal aortic aneurysms (PD-TAAAs). Fenestrated/branched endovascular repair for PD-TAAA is increasingly used in some high-volume centers, but outcomes are still limited because of the additional challenges compared to atherosclerotic thoracoabdominal aneurysms. This study was performed to evaluate the literature on fenestrated/branched endovascular repair for PD-TAAAs.

METHODS

PubMed, Embase, and the Cochrane Database were searched for relevant studies published until September 2019. Outcome data were extracted to evaluate the technical success, 30-day mortality, later survival, major complications, endoleaks, target vessel patency, and reintervention. Studies were analyzed in a pooled proportion meta-analysis.

RESULTS

In total, 143 patients from 4 studies were identified for the pooled data analysis. The pooled technical success rate was 98% (95% CI: 86%-100%). After the treatment, the overall estimated 30-day mortality rate was 3% (95% CI: 1%-8%), early spinal cord ischemia rate was 10% (95% CI: 4%-21%), early renal injury rate was 5% (95% CI: 1%-19%), endoleak rate was 33% (95% CI: 22%-47%), reintervention rate at a median follow-up of 22.5 months was 34% (95% CI: 27%-42%), and all-cause mortality rate was 12% (95% CI: 6%-24%).

CONCLUSIONS

The use of fenestrated/branched stent grafts for the treatment of PD-TAAA appears generally feasible based on the limited literature, but endoleaks and reinterventions are frequent.

Transplantation of viable mitochondria attenuates neurologic injury after spinal cord ischemia

OBJECTIVES

Spinal cord ischemia (SCI) is one of the major concerns of postoperative paraplegia during major vascular or aortic surgery. Since mitochondrial dysfunction develops at the early stage of SCI, this study tested the neuronal protective effect of transplantation of viable mitochondria to the ischemic cord in rats.

METHODS

SCI was induced by crossclamping of thoracic aorta at T6 level for 25 minutes, followed by release of vascular clip to restore aortic blood flow in the anesthetized rats. Mitochondria (100 μg) were isolated from freshly harvested soleus muscle and delivered via the internal jugular vein before releasing of vascular clip. The motor function was assessed independently up to 7 days after reperfusion. Spinal cords were harvested and analyzed for molecular and histological changes.

RESULTS

Whole-body in vivo images acquired by an in vivo imaging system confirmed the enhancement of MitoTracker fluorescence at the regions below crossclamping and in the ischemic cord. Compared with control vehicles, transplantation of mitochondria significantly improved the lower-limb locomotor function of rats subjected to cord ischemia up to 7 days after surgery. Mitochondrial transplantation suppressed the regional endoplasmic reticulum stress in the ischemic cord by attenuating CCAAT-enhancer-binding protein homologous protein expression and restoring binding immunoglobulin protein levels. In accordance, tissue levels of interleukin-6, tumor necrosis factor-α, and caspase-3 were attenuated in the mitochondrial transplanted group. Histologic examination also showed significant increase in numbers of Nissls bodies in the neurons at the ventral horn of ischemic cord following mitochondrial transplantation.

CONCLUSIONS

Our study showed that transplantation of freshly isolated mitochondria during the early stage of spinal cord ischemia-reperfusion injury suppressed the oxidative stress in endoplasmic reticulum of the injured cord, thereby reducing neuroapoptosis and improving locomotor function of rats with SCI.

Review: perspectives on renal and visceral protection during thoracoabdominal aortic aneurysm repair

Open repair of a thoracoabdominal aortic aneurysm (TAAA) is an extensive operation and associated with significant perioperative morbidities and mortality, in large part due to distal aortic ischemia secondary to aortic cross-clamping that is necessitated during repair. Distal aortic ischemia may manifest as complications of the kidneys and viscera. Postoperative renal complications range from temporarily elevated levels of creatinine resulting from impaired kidney function to acute renal failure necessitating dialysis that may persist after hospital discharge. Continued advances in the management and adjuncts associated with TAAA repair since the groundbreaking era of E.S. Crawford have led to improved postoperative outcomes following surgery, but the dramatic improvements seen in reducing rates of spinal cord deficits, mesenteric ischemia and other serious postoperative complications have not been seen in contemporary rates of postoperative renal failure. We provide an overview of the various surgical techniques and adjuncts as they relate to the management of visceral and renal ischemia.

Comparison of early patency rate and long-term outcomes of various techniques for reconstruction of segmental arteries during thoracoabdominal aortic aneurysm repair

OBJECTIVES

This study aimed to analyse the early patency rate and long-term outcomes of reattached segmental intercostal arteries using graft interposition, single-cuff anastomosis or island reconstruction.

METHODS

We selected 172 consecutive patients who underwent open surgery for the thoracoabdominal aorta with reattachment of segmental arteries between October 1999 and March 2018. The early patency of segmental arteries was analysed using enhanced computed tomography. Segmental arteries were reconstructed using graft interposition (n = 111), single-cuff anastomosis (n = 38) or island reconstruction (n = 23).

RESULTS

The hospital mortality was 6.4%. Twenty patients developed spinal cord ischaemic injury (permanent, n = 12 or transient, n = 8). Spinal cord injury was found in 16, 3 and 1 patients in the graft interposition, single-cuff anastomosis and island reconstruction groups, respectively. Overall, 475 segmental arteries were reattached (mean number per patient 2.8 ± 1.3). The overall early patency rate was 63.4%. The patency rates in island reconstruction (91.2%) and single-cuff anastomosis (77.1%) were significantly better than that in graft interposition (54.0%; P < 0.01). However, 6 patients with island reconstruction of segmental arteries had an aneurysm formation at the intercostal artery reconstruction site, of whom 4 patients underwent reoperation during follow-up. None of the patients with graft interposition or single-cuff reattachment had a patch aneurysm in segmental arteries.

CONCLUSIONS

Island reconstruction and single-cuff anastomosis might offer better patency rates and prevent spinal cord ischaemic injury than graft interposition. Because some patients with island reconstruction required reoperation for patch aneurysms in segmental arteries, single-cuff anastomosis is preferable in terms of early- and long-term outcomes.

Open surgery for descending thoracic aorta in an endovascular era

BACKGROUND

Thoracic endovascular aortic repair has become the preferred treatment for a variety of descending thoracic aortic pathologies. However, there are unresolved issues such as morphologic appearance of chronic dissection, persistent false lumen perfusion, and adequacy of landing zone. Enthusiasm for improving the technique of open aortic repair and perioperative management is fading. In this study, we would like to demonstrate how we improve our surgical outcomes by establishing a dedicated aortic multidisciplinary team at the Kawasaki Aortic Center.

METHOD

We performed a single-center retrospective study from January 2015 to December 2016. All patients with open descending thoracic aortic replacement were recruited. Preoperative patient demographic data, bypass strategies, operative details, and postoperative outcomes were reviewed.

RESULT

From January 2015 to December 2016, we treated 168 cases of descending thoracic aortic repair using a left thoracotomy. Median age was 69.0 ± 21.8 years old, and 63.1% were aortic dissection (acute, 4.8%; chronic, 58.3%); 81.3% patients underwent elective operations. Left heart bypass, deep hypothermic circulatory arrest, and partial cardiopulmonary bypass were performed in 88.6%, 9.0%, and 2.4% of patients, respectively. Mean operative time was 312 ± 94 minutes. In-hospital mortality in total was 0.6%. The rate of transient spinal cord injury was 4.7%.

CONCLUSIONS

Under a dedicated aortic multidisciplinary team, we demonstrated that open descending thoracic aorta replacement can be performed with excellent early outcomes with low reintervention rates, regardless of the nature of the aortic pathologies.