Acute aortic dissections with entry tear in the arch: A report from the International Registry of Acute Aortic Dissection

OBJECTIVE

To analyze presentation, management, and outcomes of acute aortic dissections with proximal entry tear in the arch.

METHODS

Patients enrolled in the International Registry of Acute Aortic Dissection and entry tear in the arch were classified into 2 groups: arch A (retrograde extension into the ascending aorta with or without antegrade extension) and arch B (only antegrade extension into the descending aorta or further distally). Presentation, management, and in-hospital outcomes of the 2 groups were compared.

RESULTS

The arch A (n = 228) and arch B (n = 140) groups were similar concerning the presence of any preoperative complication (68.4% vs 60.0%; P = .115), but the types of complication were different. Arch A presented more commonly with shock, neurologic complications, cardiac tamponade, and grade 3 or 4 aortic valve insufficiency and less frequently with refractory hypertension, visceral ischemia, extension of dissection, and aortic rupture. Management for both groups were open surgery (77.6% vs 18.6%; P < .001), endovascular treatment (3.5% vs 25.0%; P < .001), and medical management (16.2% vs 51.4%; P < .001). Overall in-hospital mortality was similar (16.7% vs 19.3%; P = .574), but mortality tended to be lower in the arch A group after open surgery (15.3% vs 30.8%; P = .090), and higher after endovascular (25.0% vs 14.3%; P = .597) or medical treatment (24.3% vs 13.9%; P = .191), although the differences were not significant.

CONCLUSIONS

Acute aortic dissection patients with primary entry tear in the arch are currently managed by a patient-specific approach. In choosing the management type of these patients, it may be advisable to stratify them based on retrograde or only antegrade extension of the dissection.

Development and Application of a Risk Prediction Model for In-Hospital Stroke After Transcatheter Aortic Valve Replacement: A Report From The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry

BACKGROUND

Stroke is a serious complication after transcatheter aortic valve replacement (TAVR), yet predictive models are not available. A new risk model for in-hospital stroke after TAVR was developed and used to estimate site-specific performance.

METHODS

We included 97,600 TAVR procedures from 521 sites in The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry from July 2014 to June 2017. Association between baseline covariates and in-hospital stroke was estimated by logistic regression. Discrimination was evaluated by C-statistic. Calibration was tested internally via cross-validation. Hierarchical modeling was used to estimate risk-adjusted site-specific performance.

RESULTS

Median age was 82 years, 44,926 (46.0%) were women, and 1,839 (1.9%) had in-hospital stroke. Covariates associated with stroke (odds ratio) included transapical access (1.44), access excluding transapical and transfemoral (1.77), prior stroke (1.57), prior transient ischemic attack (1.50), preprocedural shock, inotropes or mechanical assist device (1.48), smoking (1.28), porcelain aorta (1.23), peripheral arterial disease (1.21), age per 5 years (1.11), glomerular filtration rate per 5 mL/min (0.97), body surface area per m² (0.55 male; 0.43 female), and prior aortic valve (0.78) and nonaortic valvular (0.42) procedures. The C-statistic was 0.622. Calibration curves demonstrated agreement between observed and expected stroke rates. Hierarchical modeling showed 10 (1.9%) centers with significantly higher odds ratios for in-hospital stroke than their peers.

CONCLUSIONS

A risk model for in-hospital stroke after TAVR was developed from The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry and used to estimate site-specific stroke performance. This model can serve as a valuable resource for quality improvement, clinical decision making, and patient counseling.

Association of Renin-Angiotensin Inhibitor Treatment With Mortality and Heart Failure Readmission in Patients With Transcatheter Aortic Valve Replacement

IMPORTANCE

Data are lacking on the effect of a renin-angiotensin system (RAS) inhibitor prescribed after transcatheter aortic valve replacement (TAVR). Treatment with a RAS inhibitor may reverse left ventricular remodeling and improve function.

OBJECTIVE

To investigate the association of prescription of a RAS inhibitor and outcomes after TAVR.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study of TAVR procedures performed in the United States (using the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapies Registry) between July 2014 and January 2016 that were linked to Medicare claims data (final date of follow-up: March 31, 2017). To account for differences in demographics, echocardiographic findings, and in-hospital complications, 1:1 propensity matching was performed.

EXPOSURES

Initial hospital discharge prescription of a RAS inhibitor after TAVR.

MAIN OUTCOMES AND MEASURES

Primary outcomes were all-cause death and readmission due to heart failure at 1 year after discharge, which were considered separately. The secondary outcome was health status assessed by the Kansas City Cardiomyopathy Questionnaire (KCCQ; score range: 0-100, with a higher score indicating less symptom burden and better quality of life; a small effect size was defined as 5 points) at 1 year.

RESULTS

Among 21 312 patients who underwent TAVR at 417 US sites, 8468 patients (39.7%) were prescribed a RAS inhibitor at hospital discharge. After propensity matching, 15 896 patients were included (mean [SD] age, 82.4 [6.8] years; 48.1% were women; mean [SD] left ventricular ejection fraction [LVEF], 51.9% [11.5%]). Patients with a prescription for a RAS inhibitor vs those with no prescription had lower mortality rates at 1 year (12.5% vs 14.9%, respectively; absolute risk difference [ARD], -2.4% [95% CI, -3.5% to -1.4%]; hazard ratio [HR], 0.82 [95% CI, 0.76 to 0.90]) and lower heart failure readmission rates at 1 year (12.0% vs 13.8%; ARD, -1.8% [95% CI, -2.8% to -0.7%]; HR, 0.86 [95% CI, 0.79 to 0.95]). When stratified by LVEF, having a prescription for a RAS inhibitor vs no prescription was associated with lower 1-year mortality among patients with preserved LVEF (11.1% vs 13.9%, respectively; ARD, -2.81% [95% CI, -3.95% to -1.67%]; HR, 0.78 [95% CI, 0.71 to 0.86]), but not among those with reduced LVEF (18.8% vs 19.5%; ARD, -0.68% [95% CI, -3.52% to 2.20%]; HR, 0.95 [95% CI, 0.81 to 1.12]) (P = .04 for interaction). Of 15 896 matched patients, 4837 (30.4%) were included in the KCCQ score analysis and improvements at 1 year were greater in patients with a prescription for a RAS inhibitor vs those with no prescription (median, 33.3 [interquartile range, 14.2 to 51.0] vs 31.3 [interquartile range, 13.5 to 51.1], respectively; difference in improvement, 2.10 [95% CI, 0.10 to 4.06]; P < .001), but the effect size was not clinically meaningful.

CONCLUSIONS AND RELEVANCE

Among patients who underwent TAVR, receiving a prescription for a RAS inhibitor at hospital discharge compared with no prescription was significantly associated with a lower risk of mortality and heart failure readmission. However, due to potential selection bias, this finding requires further investigation in randomized trials.

Does the melatonin receptor 1B gene polymorphism have a role in postoperative delirium?

INTRODUCTION

Patients undergoing cardiac surgery are at high risk for postoperative delirium, which is associated with longer hospital and intensive care lengths of stays, increased morbidity and mortality. Because sleep disturbances are common in delirium, melatonin has been an area of interest in the treatment of delirium. The rs10830963 single nucleotide polymorphism of the melatonin receptor 1B gene can cause pathological dysfunction of this receptor and is associated with delayed morning offset of melatonin. We hypothesized patients undergoing aortic cardiac surgery who have the risk genotype of a melatonin receptor 1B polymorphism would have a higher incidence of postoperative delirium.

METHODS

Ninety-eight patients undergoing aortic root or valve surgery underwent analysis for melatonin receptor 1B single nucleotide polymorphism, rs10830963. Using a validated method, CHART-DEL, all charts were retrospectively reviewed and scored for the presence of delirium while blinded to the results of the melatonin receptor 1B gene polymorphism.

RESULTS

Genotyping for melatonin receptor 1B polymorphism was acceptable in 76 subjects of European descent of which 18 (23.7%) had delirium. Four of seven subjects with the risk genotype had delirium versus only 20.3% of subjects without the risk genotype. This carried an odds ratio of 5.2 (1.0, 26.1), p = 0.050.

CONCLUSION

This observation suggests a role of the risk genotype of a melatonin receptor 1B polymorphism in the development of postoperative delirium. These hypotheses generating results warrant further prospective studies in a larger cohort group with delirium, circadian rhythm and melatonin assessments.

Cognition and Cerebral Infarction in Older Adults After Surgical Aortic Valve Replacement

BACKGROUND

Aortic valve replacement (AVR) for calcific aortic stenosis is associated with high rates of perioperative stroke and silent cerebral infarcts on diffusion-weighted magnetic resonance imaging (MRI), but cognitive outcomes in elderly AVR patients compared with individuals with cardiac disease who do not undergo surgery are uncertain.

METHODS

One hundred ninety AVR patients (mean age 76 ± 6 years) and 198 non-surgical participants with cardiovascular disease (mean age 74 ± 6 years) completed comprehensive cognitive testing at baseline (preoperatively) and 4 to 6 weeks and 1 year postoperatively. Surgical participants also completed perioperative stroke evaluations, including postoperative brain MRI. Mixed model analyses and reliable change scores examined cognitive outcomes. Stroke outcomes were evaluated in participants with and without postoperative cognitive dysfunction.

RESULTS

From reliable change scores, only 12.4% of the surgical group demonstrated postoperative cognitive dysfunction at 4 to 6 weeks and 7.5% at 1 year. Although the surgical group had statistically significantly lower scores in working memory/inhibition 4 to 6 weeks after surgery, the groups did not differ at 1 year. In surgical participants, postoperative cognitive dysfunction was associated with a greater number (p < 0.01) and larger total volume (p < 0.01) of acute cerebral infarcts on MRI.

CONCLUSIONS

In high-risk, aged participants undergoing surgical AVR for aortic stenosis, postoperative cognitive dysfunction was surprisingly limited and was resolved by 1 year in most. Postoperative cognitive dysfunction at 4 to 6 weeks was associated with more and larger acute cerebral infarcts.

Techniques and outcomes of secondary open repair for chronic dissection after acute repair of type A aortic dissection

Despite successful repair of acute type A aortic dissection (TAAD), the distal false lumen may remain patent resulting in progressive degeneration of the remaining distal aorta. This can lead to aneurysmal dilatation and risk of rupture. Open distal reoperation to replace the residually dissected thoraco-abdominal aorta may be accomplished with acceptable morbidity and mortality in experienced hands. This can be facilitated when the index operation for acute TAAD is tailored to exclude all primary tears and set the arch and descending aorta for a subsequent open, endovascular or hybrid procedure.

Reframing the Biological Basis of Neuroprotection Using Functional Genomics: Differentially Weighted, Time-Dependent Multifactor Pathogenesis of Human Ischemic Brain Damage

Background: Neuroprotection studies are generally unable to demonstrate efficacy in humans. Our specific hypothesis is that multiple pathophysiologic pathways, of variable importance, contribute to ischemic brain damage. As a corollary to this, we discuss the broad hypothesis that a multifaceted approach will improve the probability of efficacious neuroprotection. But to properly test this hypothesis the nature and importance of the multiple contributing pathways needs elucidation. Our aim is to demonstrate, using functional genomics, in human cardiac surgery procedures associated with cerebral ischemia, that the pathogenesis of perioperative human ischemic brain damage involves the function of multiple variably weighted proteins involving several pathways. We then use these data and literature to develop a proposal for rational design of human neuroprotection protocols.

Methods: Ninety-four patients undergoing deep hypothermic circulatory arrest (DHCA) and/or aortic valve replacement surgery had brain damage biomarkers, S100β and neurofilament H (NFH), assessed at baseline, 1 and 24 h post-cardiopulmonary bypass (CPB) with analysis for association with 92 single nucleotide polymorphisms (SNPs) (selected by co-author WAK) related to important proteins involved in pathogenesis of cerebral ischemia.

Results: At the nominal significance level of 0.05, changes in S100β and in NFH at 1 and 24 h post-CPB were associated with multiple SNPs involving several prospectively determined pathophysiologic pathways, but were not individually significant after multiple comparison adjustments. Variable weights for the several evaluated SNPs are apparent on regression analysis and, notably, are dissimilar related to the two biomarkers and over time post CPB. Based on our step-wise regression model, at 1 h post-CPB, SOD2, SUMO4, and GP6 are related to relative change of NFH while TNF, CAPN10, NPPB, and SERPINE1 are related to the relative change of S100B. At 24 h post-CPB, ADRA2A, SELE, and BAX are related to the relative change of NFH while SLC4A7, HSPA1B, and FGA are related to S100B.

Conclusions: In support of the proposed hypothesis, association SNP data suggest function of specific disparate proteins, as reflected by genetic variation, may be more important than others with variation at different post-insult times after human brain ischemia. Such information may support rational design of post-insult time-sensitive multifaceted neuroprotective therapies.

Simplifying aortic arch surgery: open zone 2 arch with single branched thoracic endovascular aortic repair completion

Background

Distal aortic complications from acute DeBakey I dissection repair are an important source of late morbidity and mortality. We present an early experience of using a novel single-branched thoracic aortic endograft in conjunction with open techniques to treat acute DeBakey I aortic dissection.

Methods

The patients in this series include five hyperacute dissections managed with a combined zone 2 partial arch replacement and placement of a zone 2 single subclavian branch endograft.

Results

There were no perioperative mortalities, strokes, or spinal cord ischemia in any patients at either stage of the procedure. At follow-up imaging, no patients had anterograde flow into the false lumen. All patients experienced false lumen thrombosis in the stented portion of the aorta.

Conclusions

This combination of open repair techniques and the use of a novel branched endograft resulted in excellent early outcomes in this pioneer series. Further investigation of these techniques in a prospective fashion is warranted.

Abstract 695: Rage-mDia1 Mediates Vascular Remodeling in Angiotensin Ii Induced Thoracic Aortic Aneurysm

Background: The Receptor for Advanced Glycation End Products (RAGE), when activated, induces irreversible vascular tissue injury by promoting pro-oxidative and pro-inflammatory signaling pathways. RAGE signal transduction requires the engagement of RAGE cytoplasmic domain with the formin Diaphanous 1 (mDia1) and results in the release of soluble RAGE in the circulation. We have previously demonstrated that the RAGE/sRAGE axis is involved in the development and progression of thoracic aortic aneurysm (TAA) in humans and mice. Elevated levels of sRAGE are found in aneurysmal patients and in mouse models of TAA. In addition, RAGE inhibition counteracts aortic dilatation and the release of sRAGE in the circulation. We hypothesize that RAGE induced vascular remodeling in TAA is mediated by mDia1.

Methods: AngII infusion (1000 ng/Kg/min) was performed in C57BL6 male mice, fed with hypercolesterolaemic diet. Mice were treated for 4 weeks with losartan or with a RAGE antagonist (RAP). Ascending aortas of treated animals were harvested at day 28 post-infusion. Aortic dilatation and degeneration were assessed by echocardiography and histology. Immunofluorescence and Real Time PCR were performed to evaluate the expression of RAGE, mDia1, extracellular matrix proteins (ECM) and pro-inflammatory genes.

Results: AngII infusion induces ascending aorta dilatation and medial thickening characterized by a substantial ECM deposition. RAGE and mDia1 expression is significantly increased in the aneurysmal aorta of mice chronically infused with AngII together with up-regulation of pro-inflammatory molecules (IL-6, MCP-1, IL1beta, TLR4, CCR2) and markers of extracellular matrix remodeling (Col1, Col3, MMP-2 and MMP12). Inhibition of RAGE dampens mDia1 expression and significantly reduces medial pro-inflammatory and pro-fibrotic signals while counteracting aneurysm formation.

Conclusion: Formin mDia1 is involved in RAGE mediated TAA formation. Strategies that block RAGE-mDia1 interaction may unveil novel therapeutic approaches for the treatment of TAA.

Hybrid arch surgery challenges other forms of arch treatment

INTRODUCTION

The gold standard for aortic arch replacement remains total arch replacement (TAR) procedure. Hybrid techniques, utilizing a combination of open and endovascular approaches, have been developed with goal of lowering postoperative mortality and morbidity, as well as providing an alternative therapy for patients who are elderly, have significant comorbid burden, or patients in whom circulatory arrest may pose significant risk.

EVIDENCE ACQUISITION

To date, there are no prospective randomized trials comparing hybrid aortic ach procedures to TAR. Further, many case series describing the outcomes of hybrid procedures involve cohorts with significant comorbidities and, thus, comparison with historical, total arch replacement controls is difficult. However, retrospective studies comparing hybrid arch procedures to TAR are accruing including a Society of Thoracic Surgery Database review conducted by our institution.

EVIDENCE SYNTHESIS

Review of the literature demonstrates that the optimal surgical management of aortic arch pathology remains a clinical challenge. Several institutions, including our own, have demonstrated that hybrid arch procedures can be safely performed with acceptable postoperative outcomes and improvements in aortic remodeling. However, many other groups have advocated for the use of hybrid procedures only in the setting of high risk patients due to concerns for increased risk as compared to total arch replacement. At present, the majority of the available data suggests that hybrid arch procedures are most frequently reserved for patients who are of significant operative risk.

CONCLUSIONS

Hybrid arch procedures are frequently employed for high risk patients. The available data demonstrates that in this population these procedures produce satisfactory outcomes.

The role of extracorporeal membrane oxygenator therapy in the setting of Type A aortic dissection

BACKGROUND AND AIM

Patients presenting with type A aortic dissection (TAAD) present with a wide clinical spectrum ranging from hemodynamic stability to multiorgan malperfusion with cardiovascular collapse. Extracorporeal membrane oxygenator (ECMO) therapy is increasingly being utilized as salvage therapy in patients with acute cardiopulmonary failure and for post-cardiotomy shock. We sought to determine the utility of ECMO implementation post-TAAD repair.

METHODS

The Pennsylvania Health Care Cost Containment Council (PHC4) database, maintained by an independently functioning state agency, was retrospectively reviewed from 2004 to 2014. Patients with a primary diagnosis of aortic dissection requiring ECMO support during the same hospital visit were included in the analysis.

RESULTS

Thirty-nine patients were identified with diagnosis/procedure codes for TAAD repair and ECMO, of which four patients did not undergo TAAD repair. Of the remaining 35, 31 patients underwent open repair, and four patients underwent TEVAR. ECMO was instituted on the same day of TAAD surgery in 27 (69.2%) patients, and on post-operative day >1 in eight (20.5%) patients. Overall mortality in patients who were on ECMO the same day was 88.9% and 87.5% when it was done after the first post-operative day. All four patients with TAAD who underwent ECMO only died. Median time from ECMO implantation to death was 1.0 day.

CONCLUSIONS

Requirement for ECMO support in acute aortic dissection is associated with extremely high mortality irrespective of when the intervention is performed.