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Objective: To demonstrate the role of perioperative stroke as an independent risk factor for in-hospital morbidity and mortality after mitral valve surgery and review the trends in the early outcomes of mitral valve surgery over the past decade., Design: Using data from the National Inpatient Sample database for analysis, all patients who underwent isolated mitral valve procedures were identified using International Classification of Diseases-Ninth Revision codes. Univariate and multivariate analyses of risk factors of in-hospital mortality and morbidity were performed., Setting: Multi-institutional., Participants: The study comprised patients who underwent mitral valve procedures from 1999 to 2011., Interventions: Mitral valve repair or replacement., Measurements and Main Results: Data on 21,821 patients showed an in-hospital mortality of 5.5% and morbidity of 63.30% (p<0.05). Perioperative strokes were experienced by 3.89% of the cohort after isolated mitral valve surgery (p<0.05). Independent predictors of adverse outcomes were age, female sex, emergency surgery, arrhythmias, hypertension, renal failure, coagulopathy, neurologic disorders, weight loss, anemia, postoperative cardiac arrest, and myocardial infarction. Perioperative strokes were found to be the strongest risk factor for postoperative mortality (odds ratio 2.34, 95% confidence interval 1.83-2.98) and morbidity (odds ratio 4.53, 95% confidence interval 3.34-6.15)., Conclusion: Age, female sex, emergency surgery, arrhythmias, hypertension, renal failure, coagulopathy, neurologic disorders, weight loss, fluid and electrolyte imbalance, anemia, postoperative cardiac arrest, and myocardial infarction were found to be significant predictors of morbidity and mortality after mitral valve surgery, with perioperative strokes posing the strongest risk. The trends in the last 10 years indicated a decrease in mortality and an increase in morbidity. Preoperative risk stratification and intraoperative identification for impending strokes appear warranted., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: Postoperative myocardial infarction remains a serious complication in cardiac surgery. The incidence and impact of this condition in acute type A aortic dissection are poorly understood., Methods: A total of 1445 patients with acute type A aortic dissection who underwent surgery were enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2013. Individuals with preoperative myocardial infarction at hospital presentation and a history of myocardial infarction were excluded. Patients with postoperative myocardial infarction (n = 38, 2.6%) were compared with those without postoperative myocardial infarction (n = 1407, 97.4%)., Results: The postoperative myocardial infarction group was more often of white race (100% vs 90%, P = .043) with bicuspid aortic valve (15.6% vs 4.5%, P = .015). Imaging demonstrated more aortic root involvement (75.8% vs 49.5%, P = .003), pericardial effusion (65.5% vs 44.1%, P = .022), and coronary artery compromise (27.3% vs 10.2%, P = .022). Patients with postoperative myocardial infarction were more frequently hypotensive or in shock during surgery (42.9% vs 25.5%, P = .021). Patients with postoperative myocardial infarction were more likely to have undergone root replacement (54.5% vs 33.3%, P = .011), coronary artery bypass grafting (28.6% vs 7.4%, P < .001), or aortic valve replacement (40.0% vs 23.8%, P = .027), and less likely to have had complete arch replacement (2.8% vs 14.0%, P = .050). Median circulatory arrest time was higher in postoperative myocardial infarction (60 vs 38 minutes, P = .024). In-hospital mortality (57.9% vs 16.3%, P < .001) and Kaplan-Meier estimates of 5-year mortality (P = .007) were distinctly higher in postoperative myocardial infarction., Conclusions: Postoperative myocardial infarction is a devastating complication of type A aortic dissection repair. It is associated with bicuspid aortic valve, root involvement, pericardial effusion, and extent of surgical repair. Patients with postoperative myocardial infarction have higher serious postoperative complications, in-hospital mortality, and 5-year mortality rates than those without postoperative myocardial infarction., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: The primary aim of this meta-analysis was to quantify the impact of perioperative strokes on stroke-related mortality after open mitral valve (MV) procedures were performed., Methods: An electronic search of the PubMed, Embase, and the Web of Science databases was performed to retrieve articles published up to December 2015, relevant to patients undergoing MV procedures. Data were extracted from the final list of 25 studies to calculate a summary OR for 30-day stroke-related mortality., Results: The stroke rate in the total sample population was 1.62% (73/4,498). The 30-day all-cause mortality rate was 3.51% (158/4,498). The percentage of total deaths caused by stroke was 6.87%. The summary OR of stroke-related mortality following MV procedures was estimated to be 7.22 (95% CI 4.13-12.63, p < 0.0001). A subgroup analysis was done for studies involving concomitant MV surgery and coronary artery bypass grafting. The summary estimate of the subgroup showed an OR of 8.508 (95% CI 1.552-46.622, p = 0.0136)., Conclusion: Perioperative strokes following open MV procedures may be associated with more than 7 times greater odds of 30-day stroke-related mortality. They appear to be more commonly occurring than what is reported by current literature, making further studies investigating possible mechanisms and preventive measures a priority., (© 2017 S. Karger AG, Basel.)

Importance: Transcatheter aortic valve replacement (TAVR) is now a well-accepted alternative to surgical AVR (SAVR) for patients with symptomatic aortic stenosis at increased operative risk. There is interest in whether TAVR would benefit patients at lower risk., Objective: The Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) has trended downward in US TAVR trials and the STS/American College of Cardiology Transcatheter Valve Therapy Registry. We hypothesized that if the Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM) alone is sufficient to define decreased risk, the contribution to survival based on the degree of invasiveness of the TAVR procedure will decrease, making it more difficult to show improved survival and benefit over SAVR., Design, Setting, and Participants: The CoreValve US Pivotal High Risk Trial was a multicenter, randomized, noninferiority trial. This retrospective analysis evaluated patients who underwent an attempted implant and had an STS PROM of 7% or less. The trial was performed at 45 US sites. Patients had severe aortic stenosis and were at increased surgical risk based on their STS PROM score and other risk factors., Interventions: Eligible patients were randomly assigned (1:1) to self-expanding TAVR or to SAVR., Main Outcomes and Measures: We retrospectively stratified patients by the overall median STS PROM score (7%) and analyzed clinical outcomes and quality of life using the Kansas City Cardiomyopathy Questionnaire in patients with an STS PROM score of 7% or less., Results: The mean (SD) ages were 81.5 (7.6) years for the TAVR group and 81.2 years (6.6) for the SAVR group. A little more than half were men (57.9% in the TAVR group and 55.8% in the SAVR group). Of 750 patients who underwent attempted implantation, 383 (202 TAVR and 181 SAVR) had an STS PROM of 7% or less (median [interquartile range]: TAVR, 5.3% [4.3%-6.1%]; SAVR, 5.3% [4.1%-5.9%]). Two-year all-cause mortality for TAVR vs SAVR was 15.0% (95% CI, 8.9-10.0) vs 26.3% (95% CI, 19.7-33.0) (log rank P = .01). The 2-year rate of stroke for TAVR vs SAVR was 11.3% vs 15.1% (log rank P = .50). Quality of life by the Kansas City Cardiomyopathy Questionnaire summary score showed significant and equivalent increases in both groups at 2 years (mean [SD] TAVR, 20.0 [25.0]; SAVR, 18.6 [23.6]; P = .71; both P < .001 compared with baseline). Medical benefit, defined as alive with a Kansas City Cardiomyopathy Questionnaire summary score of at least 60 and a less than 10-point decrease from baseline, was similar between groups at 2 years (TAVR, 51.0%; SAVR, 44.4%; P = .28)., Conclusions and Relevance: Self-expanding TAVR compares favorably with SAVR in high-risk patients with STS PROM scores traditionally considered intermediate risk., Trial Registration: Clinicaltrials.gov Identifier: NCT01240902.

Transcatheter aortic valve implantation (TAVI) is a rapidly evolving safe method with decreasing incidence of perioperative stroke. There is a void in literature concerning the impact of stroke after TAVI in predicting 30-day stroke-related mortality. The primary aim of this meta-analysis was to determine whether perioperative stroke increases risk of stroke-related mortality after TAVI. Online databases, using relevant keywords, and additional related records were searched to retrieve articles involving TAVI and stroke after TAVI. Data were extracted from the finalized studies and analyzed to generate a summary odds ratio (OR) of stroke-related mortality after TAVI. The stroke rate and stroke-related mortality rate in the total patient population were 3.07% (893 of 29,043) and 12.27% (252 of 2,053), respectively. The all-cause mortality rate was 7.07% (2,053 of 29,043). Summary OR of stroke-related mortality after TAVI was estimated to be 6.45 (95% confidence interval 3.90 to 10.66, p <0.0001). Subgroup analyses were performed among age, approach, and valve type. Only 1 subgroup, transapical TAVI, was not significantly associated with stroke-related mortality (OR 1.97, 95% confidence interval, 0.43 to 7.43, p = 0.42). A metaregression was conducted among females, New York Heart Association class III/IV status, previous stroke, valve type, and implantation route. All failed to exhibit any significant associations with the OR. In conclusion, perioperative strokes after TAVI are associated with >6 times greater risk of 30-day stroke-related mortality. Transapical TAVI is not associated with increased stroke-related mortality in patients who suffer from perioperative stroke. Preventative measures need to be taken to alleviate the elevated rates of stroke after TAVI and subsequent direct mortality., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Endothelial nitric oxide (NO) synthase (eNOS) has been implicated in the development of bicuspid aortic valve (BAV) and with differential expression in the ascending aorta of BAV patients. However, little is known about functional disruptions in the eNOS pathway and the effect on BAV-associated aortic dilatation. We tested the hypothesis that eNOS function is regionally diminished in ascending thoracic aortic aneurysms associated with BAV., Methods: Thoracic aortic aneurysms specimens were collected from patients with BAV (n = 21) or tricuspid aortic valve (n = 12). Tissue samples were harvested from three circumferential regions corresponding to locations above the right, left, and noncoronary sinuses. Adventitial-stripped specimens containing media and intima only were analyzed for NO synthase 3 gene expression and total eNOS protein. Indicators of eNOS activity (pSer1177-eNOS) and NO bioavailability (phosphorylation of vasodilator-stimulated phosphoprotein at Ser239) were also measured., Results: NO synthase 3 and eNOS protein were elevated in the right aortic region of BAV specimens compared with tricuspid aortic valve specimens. Activation of eNOS, as indicated by pSer1177-eNOS, was higher in BAV specimens across all regions. Despite increases in eNOS and pSer1177-eNOS, BAV specimens displayed no change in pSer239-vasodilator-stimulated phosphoprotein compared with tricuspid aortic valve specimens., Conclusions: BAV is associated with regional disruptions in the eNOS pathway, most markedly in the right aortic region. The discrepancy between increased eNOS activity and the absence of increased NO bioavailability in this region provides insight into physiologic mechanisms potentially underlying the asymmetric dilatation pattern observed in BAV., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: Repair for ischemic mitral regurgitation with undersized annuloplasty is characterized by high recurrence rates. We sought to determine the value of pre-repair 3-dimensional echocardiography over 2-dimensional echocardiography in predicting recurrence at 6 months., Methods: Intraoperative transesophageal 2-dimensional echocardiography and 3-dimensional echocardiography were performed in 50 patients undergoing undersized annuloplasty for ischemic mitral regurgitation. Two-dimensional echocardiography annular diameter and tethering parameters were measured in the apical 2- and 4-chamber views. A customized protocol was used to assess 3-dimensional annular geometry and regional leaflet tethering. Recurrence (grade ≥2) was assessed with 2-dimensional transthoracic echocardiography at 6 months., Results: Preoperative 2- and 3-dimensional annular geometry were similar in all patients with ischemic mitral regurgitation. Preoperative 2- and 3-dimensional leaflet tethering were significantly higher in patients with recurrence (n = 13) when compared with patients without recurrence (n = 37). Multivariate logistic regression revealed preoperative 2-dimensional echocardiography posterior tethering angle as an independent predictor of recurrence with an optimal cutoff value of 32.0° (area under the curve, 0.81; 95% confidence interval, 0.68-0.95; P = .002) and preoperative 3-dimensional echocardiography P3 tethering angle as an independent predictor of recurrence with an optimal cutoff value of 29.9° (area under the curve, 0.92; 95% confidence interval, 0.84-1.00; P < .001). The predictive value of the 3-dimensional geometric multivariate model can be augmented by adding basal aneurysm/dyskinesis (area under the curve, 0.94; 95% confidence interval, 0.87-1.00; P < .001)., Conclusions: Preoperative 3-dimensional echocardiography P3 tethering angle is a stronger predictor of ischemic mitral regurgitation recurrence after annuloplasty than preoperative 2-dimensional echocardiography posterior tethering angle, which is highly influenced by viewing plane. In patients with a preoperative P3 tethering angle of 29.9° or larger (especially when combined with basal aneurysm/dyskinesis), chordal-sparing valve replacement should be strongly considered., Competing Interests: Statement Authors have nothing to disclose with regard to commercial support., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to determine the relationship between aortoventricular (AoV) angulation on clinical outcomes after self-expanding transcatheter aortic valve replacement (TAVR) in patients with severe aortic stenosis who were deemed suboptimal for surgery., Background: Multidetector computed tomographic (MDCT) imaging of the aortovalvular complex has become a prerequisite for case planning with self-expanding TAVR. The effect of aortic angulation, an index of an unfolded or "horizontal" aorta, on procedural outcome after self-expanding TAVR is not known., Methods: The clinical course of 3,578 patients who received implants in the CoreValve US Clinical Trials and who had prospective MDCT estimation of the AoV angle before the procedure was reviewed. Clinical site echocardiogram assessments were used to determine the degree of residual aortic regurgitation 24 to 48 h after the procedure and at 30 days. On the basis of the measurement of the AoV angle on MDCT, patients were categorized into septiles, ranging from the lowest septile of an AoV angle <37.0° to the highest AoV angle septile of >55.0°., Results: Patients were elderly (age 83.3 ± 7.8 years) and were at high risk for surgical valve replacement (Society of Thoracic Surgeons Predicted Risk of Mortality 8.8 ± 4.7). Greater degrees of AoV angulation were correlated with older age (p < 0.0001). Although procedure time was 6.9 min longer in the highest septile (59.4 ± 35.9 min vs. 52.5 ± 35.3 min in the lowest septile; p = 0.004), there were no linear trends (p > 0.05) in the frequencies of device success, procedural success, frequencies of moderate or greater aortic regurgitation at 30 days, number of valves implanted, or need for balloon post-dilation or new pacemakers among the AoV angle septiles., Conclusions: The degree of AoV angulation does not affect early clinical outcomes self-expanding transcatheter aortic valve replacement. (Safety and Efficacy Study of the Medtronic CoreValve® System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement [Medtronic CoreValve® U.S. Pivotal Trial]; NCT01240902)., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Multidetector computed tomography is useful for determining the appropriate transcatheter heart valve (THV) size in patients with severe aortic stenosis who are suboptimal surgical candidates. The relationship between adherence to the recommended CoreValve sizing algorithm and clinical outcomes is not known., Methods and Results: We evaluated 1023 patients with severe aortic stenosis deemed high or extreme risk for surgery treated with the CoreValve THV. All patients underwent preprocedural multidetector computed tomography, and the scans were reviewed at a central analysis center using standardized software. Compliance to a recommended sizing algorithm was used to identify patients with below-range, in-range, and above-range THV sizing. A device annular sizing ratio (DAR) was also calculated based on the native annulus perimeter and perimeter of the selected THV. Clinical end points included the presence of paravalvular aortic regurgitation evaluated by an independent echocardiographic laboratory. Adherence to the sizing algorithm was highest with a 31-mm THV (92.6%) and lowest with the 23-mm THV (38.5%). Below-range sizing was associated with a higher rate of moderate or severe paravalvular aortic regurgitation (15.3%) than in-range (6.5%) or above-range (10.0%; P<0.001) sizing. Higher DARs were associated with lower rates of moderate or severe paravalvular aortic regurgitation: DAR ≤10%, 17.6%; DAR 10% to 15%, 9.9%; DAR 15% to 20%, 6.3%; and DAR >20%, 4.9%; P<0.001. There was no increase in clinical events associated with higher DARs., Conclusions: Adherence to a sizing algorithm guided by multidetector computed tomography resulted in lower rates of paravalvular aortic regurgitation after self-expanding transcatheter valve replacement without an increase in complications., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01240902., (© 2016 American Heart Association, Inc.)

Objectives: This study was designed to characterize the incidence of new clinically detectable neurologic events, or any comparative change in indices of higher cognitive function following transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) within the framework of a prospective, randomized clinical trial for high-risk patients., Methods: High-risk patients (predicted SAVR mortality 15%) with severe aortic stenosis (n = 750) were randomized 1:1 to TAVR or SAVR and underwent evaluation using the National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale assessment at each follow-up and any suspected event. Neurologic outcomes were ascertained by a neurologist and further evaluated by Mini-Mental State Examination (MMSE), visual fields testing, gait assessment, hand function, writing evaluation, and drawing assessment., Results: The 30-day, 1-year, and 2-year stroke rates were 4.9%, 8.7%, and 10.9%, respectively, for TAVR and 6.2%, 12.5%, and 16.6%, respectively, for SAVR (P = .46, .11, and .05, respectively). All-cause mortality in patients with a major stroke was 83.3% for TAVR and 54.5% for SAVR at 2 years (P = .29). Late major stroke was disproportionately higher (23.8% at 2 years) among patients with poor iliofemoral access randomized to SAVR. Peripheral vascular disease and falls within 6 months predicted early stroke, and severe aortic calcification and high Charlson score (≥5) predicted 1-year stroke post-TAVR. NIHSS and MMSE scores trended higher after SAVR than after TAVR. Lack of dual antiplatelet therapy use during and after TAVR was associated with early stroke., Conclusions: This study defines an equivalent postprocedural stroke risk, stroke extent, and degree of cognitive change after TAVR or SAVR in a high-risk population, and also defines several predictors of stroke after TAVR., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Type A acute aortic dissection (TAAD) is a disease that has a catastrophic impact on a patient's life and emergent surgery represents a key goal of early treatment. Despite continuous improvements in imaging techniques, medical therapy and surgical management, early mortality in patients undergoing TAAD repair still remains high, ranging from 17% to 26%. In this setting, the International Registry of Acute Aortic Dissection (IRAD), the largest worldwide registry for acute aortic dissection, was established to assess clinical characteristics, management and outcomes of TAAD patients. The present review aimed to evaluate and comment on outcomes of TAAD surgery as reported from IRAD series.

Incorporation of collagen structural information into the study of biomechanical behavior of ascending thoracic aortic (ATA) wall tissue should provide better insight into the pathophysiology of ATA. Structurally motivated constitutive models that include fiber dispersion and recruitment can successfully capture overall mechanical response of the arterial wall tissue. However, these models cannot examine local microarchitectural features of the collagen network, such as the effect of fiber disruptions and interaction between fibrous and non-fibrous components, which may influence emergent biomechanical properties of the tissue. Motivated by this need, we developed a finite element based three-dimensional structural model of the lamellar units of the ATA media that directly incorporates the collagen fiber microarchitecture. The fiber architecture was computer generated utilizing network features, namely fiber orientation distribution, intersection density and areal concentration, obtained from image analysis of multiphoton microscopy images taken from human aneurysmal ascending thoracic aortic media specimens with bicuspid aortic valve (BAV) phenotype. Our model reproduces the typical J-shaped constitutive response of the aortic wall tissue. We found that the stress state in the non-fibrous matrix was homogeneous until the collagen fibers were recruited, but became highly heterogeneous after that event. The degree of heterogeneity was dependent upon local network architecture with high stresses observed near disrupted fibers. The magnitude of non-fibrous matrix stress at higher stretch levels was negatively correlated with local fiber density. The localized stress concentrations, elucidated by this model, may be a factor in the degenerative changes in aneurysmal ATA tissue., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: In patients with severe aortic stenosis at increased risk for surgery, self-expanding transcatheter aortic valve replacement (TAVR) is associated with improved 2-year survival compared with surgery., Objectives: This study sought to determine whether this clinical benefit was sustained over time., Methods: Patients with severe aortic stenosis deemed at increased risk for surgery by a multidisciplinary heart team were randomized 1:1 to TAVR or open surgical valve replacement (SAVR). Three-year clinical and echocardiographic outcomes were obtained in those patients with an attempted procedure., Results: A total of 797 patients underwent randomization at 45 U.S. centers; 750 patients underwent an attempted procedure. Three-year all-cause mortality or stroke was significantly lower in TAVR patients (37.3% vs. 46.7% in SAVR; p = 0.006). Adverse clinical outcome components were also reduced in TAVR patients compared with SAVR patients, including all-cause mortality (32.9% vs. 39.1%, respectively; p = 0.068), all stroke (12.6% vs. 19.0%, respectively; p = 0.034), and major adverse cardiovascular or cerebrovascular events (40.2% vs. 47.9%, respectively; p = 0.025). At 3 years aortic valve hemodynamics were better with TAVR patients (mean aortic valve gradient 7.62 ± 3.57 mm Hg vs. 11.40 ± 6.81 mm Hg in SAVR; p < 0.001), although moderate or severe residual aortic regurgitation was higher in TAVR patients (6.8% vs. 0.0% in SAVR; p < 0.001). There was no clinical evidence of valve thrombosis in either group., Conclusions: Patients with severe aortic stenosis at increased risk for surgery had improved 3-year clinical outcomes after TAVR compared with surgery. Aortic valve hemodynamics were more favorable in TAVR patients without differences in structural valve deterioration. (Safety and Efficacy Study of the Medtronic CoreValve(®) System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902)., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: Ascending thoracic aortic aneurysm (ATAA) in patients with bicuspid aortic valve (BAV) commonly dilate asymmetrically compared with patients with tricuspid aortic valve (TAV). This discrepancy in aneurysm geometry led us to hypothesize that microarchitectural differences underlie the observed asymmetric dilatation pattern. The purpose of this study was to characterize the microarchitectural distinctions of the extracellular matrix of the 2 phenotypes with a focus on the proportion of radially oriented elastin and collagen fibers in different circumferential aortic regions., Methods: Aortic tissue rings were obtained just distal to the sinotubular junction from patients with BAV or TAV undergoing elective aneurysm repair. They were sectioned into three circumferentially based regions according to adjacent aortic sinus segment (left coronary sinus [L], right coronary sinus [R], or noncoronary sinus [N]). Multiphoton microscopy was used to quantify and characterize the number of radially oriented elastin and collagen fibers., Results: There were fewer radially oriented fibers in medial region N and medial-intimal region R of BAV-ATAAs when compared with TAV-ATAAs (medial region N, amplitude of angular undulation of elastin = 10.67° ± 1.35° vs 15.58° ± 1.91°; P = .041; medial-intimal region R, amplitude of angular undulation of elastin = 9.83° ± 0.83° vs 14.72° ± 1.64°; P = .015). Conversely, fibers became more radially oriented in the medial-intimal region L of BAV-ATAA when compared with TAV-ATAA (amplitude of angular undulation of collagen = 18.67° ± 0.95° vs 14.56° ± 1.37°; P = .041)., Conclusions: The differential pattern of fiber orientation noted between L and N-R regions help explain the unique pattern of greater curvature dilatation of BAV-ATAA. The distinctions noted in matrix microarchitecture may form the basis of differing aneurysm geometries and aortic wall integrities in ATAAs arising in these different valve morphologies., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Patients with low left ventricular ejection fractions and low-flow, low-gradient aortic stenosis (AS) represent a challenging cohort with high morbidity and mortality. The prevalence and clinical impact of right ventricular dysfunction (RVD) on risk stratification and prognosis in these patients is unknown., Methods: A retrospective analysis was performed of 65 patients with low-flow, low-gradient AS who underwent low-dose dobutamine stress echocardiography to determine AS severity and to ascertain flow reserve status (≥20% stroke volume increase). Clinical, demographic, and imaging data were prospectively collected. Per guidelines, RVD was defined as tricuspid annular plane systolic excursion < 16 mm in the apical four-chamber view and measured at baseline. Cox proportional hazards modeling was used to risk-adjust comparisons for the end point of all-cause mortality., Results: The mean age was 74 ± 9 years, the mean left ventricular ejection fraction was 29 ± 10%, the mean indexed aortic valve (AV) area was 0.49 ± 0.1 cm(2)/m(2), and the mean AV gradient 22 ± 7 mm Hg. RVD was present in 37 patients (57% of the study cohort). After a median follow-up period of 13 months (interquartile range, 5-30 months), there were 29 AV replacements and 30 deaths. The presence of RVD (hazard ratio, 2.86; 95% CI, 1.21-6.75; P = .02) was an independent risk factor associated with all-cause mortality despite many adjustments for potential clinical and echocardiographic confounders such as AV replacement, Society of Thoracic Surgeons Predicted Risk of Mortality score, severity of tricuspid regurgitation, and left ventricular global longitudinal strain., Conclusions: Baseline RVD is prevalent in patients with low-flow, low-gradient AS undergoing dobutamine stress echocardiography. Quantification of right ventricular systolic function in these complex patients provides important prognostic value and risk stratification adjunctive to Society of Thoracic Surgeons Predicted Risk of Mortality score and should be incorporated into the decision-making process., (Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.)

Objectives: We compared the incidence of prosthesis-patient mismatch (PPM) between transcatheter aortic valve replacement (TAVR) using a self-expanding bioprosthesis and surgical aortic valve replacement (SAVR) in the CoreValve US High Risk Pivotal Trial. We sought to determine the influence of PPM on clinical outcomes., Methods: Patients with severe aortic stenosis and at increased risk for surgery were randomized 1:1 to TAVR or SAVR. Postoperative PPM was defined by the effective orifice area index (EOAi) as severe PPM (EOAi ≤ 0.65 cm(2)/m(2)) and no severe PPM (EOAi > 0.65 cm(2)/m(2)); clinical outcomes were analyzed in the TAVR arm (n = 389) and SAVR arm (n = 353). Left ventricular mass index and regression were analyzed at baseline and 1 year., Results: The incidence of severe PPM in the SAVR group at 1 year was 25.7% versus 6.2% in the TAVR group (P < .0001). Left ventricular mass index regression at 1 year was 6.8% for TAVR and 15.1% for SAVR in patients with severe PPM. At 1 year the rate of all-cause mortality and acute kidney injury were significantly greater in all patients (TAVR + SAVR) with severe PPM compared with no severe PPM (20.6% vs 12.0% [P = .0145] for death and 19.2% vs 8.5% [P = .0008] for acute kidney injury)., Conclusions: In patients with high surgical risk and severe aortic stenosis, severe PPM is more common in patients treated with SAVR than those treated with TAVR. Patients with severe PPM are a greater risk for death and acute kidney injury than patients without severe PPM., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Background: International registries for acute type A aortic dissection (TAAD) demonstrate stagnant operative mortality rates in excess of 20% and stroke rates of 9% to 25%, with little global emphasis on stroke reduction or carotid involvement. Cerebral malperfusion with TAAD has been linked to poorer outcome. We hypothesize that concomitant carotid dissection or complex dissection flaps in the arch play a major role in stroke development and that aggressive reconstruction of the arch and carotid arteries can improve neurologic outcomes in TAAD., Methods: A standardized protocol focused on expedient care, neurocerebral protection, and common carotid and total arch reconstruction was developed for 264 consecutive TAADs. Arch and complete carotid replacement was based on arch dissection anatomy, carotid involvement, or an intraarch tear. Neurocerebral monitoring with continuous electroencephalogram/somatosensory evoked potentials was used in all cases., Results: The postoperative stroke and hospital mortality rates were 3.4% and 9.1%, and stroke rates by extent of arch replacement were 4%, 3%, and 0% for hemiarch, total arch, and total arch with complete carotid replacement, respectively. An intraoperative change in the electroencephalogram/somatosensory evoked potentials was strongly predictive of stroke and had a negative predictive value of 98.2%., Conclusions: An algorithmic approach to TAAD including (1) rapid transport-to-incision-to-cardiopulmonary bypass established centrally, (2) neurocerebral monitoring, (3) liberal use of total arch replacement for clearly defined indications (and hemiarch for all others), and (4) common carotid arterial replacement for concomitant carotid dissections significantly improves outcomes., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Ascending thoracic aortic aneurysm (ATAA) has been associated with diminished biomechanical strength and disruption in the collagen fiber microarchitecture. Additionally, the congenital bicuspid aortic valve (BAV) leads to a distinct extracellular matrix structure that may be related to ATAA development at an earlier age than degenerative aneurysms arising in patients with the morphological normal tricuspid aortic valve (TAV). The purpose of this study was to model the fiber-reinforced mechanical response of ATAA specimens from patients with either BAV or TAV. This was achieved by combining image-analysis derived parameters of collagen fiber dispersion and alignment with tensile testing data. Then, numerical simulations were performed to assess the role of anisotropic constitutive formulation on the wall stress distribution of aneurysmal aorta. Results indicate that both BAV ATAA and TAV ATAA have altered collagen fiber architecture in the medial plane of experimentally-dissected aortic tissues when compared to normal ascending aortic specimens. The study findings highlight that differences in the collagen fiber distribution mostly influences the resulting wall stress distribution rather than the peak stress. We conclude that fiber-reinforced constitutive modeling that takes into account the collagen fiber defect inherent to the aneurysmal ascending aorta is paramount for accurate finite element predictions and ultimately for biomechanical-based indicators to reliably distinguish the more from the less 'malignant' ATAAs., (Copyright © 2015 IPEM. All rights reserved.)

Background: Valve repair for ischemic mitral regurgitation (IMR) with undersized annuloplasty rings is characterized by high IMR recurrence rates. Patient-specific preoperative imaging-based risk stratification for recurrent IMR would optimize results. We sought to determine if prerepair three-dimensional (3D) echocardiography combined with a novel valve-modeling algorithm would be predictive of IMR recurrence 6 months after repair., Methods: Intraoperative transesophageal real-time 3D echocardiography was performed in 50 patients undergoing undersized ring annuloplasty for IMR and in 21 patients with normal mitral valves. A customized image analysis protocol was used to assess 3D annular geometry and regional leaflet tethering. IMR recurrence (≥ grade 2) was assessed with two-dimensional transthoracic echocardiography 6 months after repair., Results: Preoperative annular geometry was similar in all IMR patients, and preoperative leaflet tethering was significantly higher in patients with recurrent IMR (n=13) than in patients in whom IMR did not recur (n=37) (tethering index: 3.91 ± 1.01 vs 2.90 ± 1.17, p = 0.008; tethering angles of A3: 23.5° ± 8.9° vs 14.4° ± 11.4°, p = 0.012; P2: 44.4° ± 8.8° vs 28.2° ± 17.0°, p = 0.002; and P3: 35.2° ± 6.0° vs. 18.6° ± 12.7°, p < 0.001). Multivariate logistic regression analysis revealed the preoperative P3 tethering angle as an independent predictor of IMR recurrence with an optimal cutoff value of 29.9° (area under the curve, 0.92; 95% confidence interval, 0.84 to 1.00; p < 0.001)., Conclusions: 3D echocardiography combined with valve modeling is predictive of recurrent IMR. Preoperative regional leaflet tethering of segment P3 is a strong independent predictor of IMR recurrence after undersized ring annuloplasty. In patients with a preoperative P3 tethering angle of 29.9° or larger, chordal-sparing valve replacement rather than valve repair should be strongly considered., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Importance: Aortic clamping technique has been implicated in stroke risk at the time of on-pump coronary artery bypass grafting (CABG) procedures. We hypothesized that partial aortic clamping (PAC) use in performing proximal coronary anastomosis does not increase risk of stroke., Objective: To determine whether postoperative stroke incidence is influenced by single aortic clamping (SAC) or side-biting PAC use in performing proximal anastomosis during CABG procedures., Design, Setting, and Participants: In a retrospective cohort study, we analyzed data from 1819 patients who underwent conventional, isolated, nonemergent, first-time, arrested-heart, on-pump CABG at a single US major academic, tertiary/quaternary medical center from January 1, 2005, to December 31, 2013. Postoperative stroke was defined according to Society of Thoracic Surgeons (STS) criteria as any confirmed neurological deficit of abrupt onset that did not resolve within 24 hours. Institutional STS data including STS predicted risk of postoperative stroke score were used to compare patients receiving proximal aortic anastomoses performed with either SAC (n = 1107) or combined PAC (n = 712) techniques., Exposures: Use of SAC or PAC in performing proximal coronary anastomosis., Main Outcomes and Measures: Thirty-day periprocedural postoperative stroke rates., Results: There were no significant differences in preoperative risk or STS predicted risk of mortality between groups. Patients in the SAC group had longer myocardial ischemic time compared with those in the PAC group (mean [SD], 73.2 [22.8] vs 66.5 [22.8] minutes, respectively; P < .001) but shorter overall perfusion time (mean [SD], 96.6 [30.1] vs 102.2 [30.1] minutes, respectively; P < .001). The 30-day observed mortality rates between the SAC and PAC groups were equally low (21 of 1107 patients [1.9%] vs 13 of 712 patients [1.8%], respectively; P > .99) and congruent with STS predicted risk of mortality. Preoperative STS predicted risk of postoperative stroke scores were nearly identical between the SAC and PAC groups (mean [SD], 1.5% [1.4%] vs 1.6% [1.4%]; P = .95), and the 30-day actual observed postoperative stroke rates between the SAC and PAC groups were similar (17 of 1107 patients [1.5%] vs 10 of 712 patients [1.4%], respectively; P > .99)., Conclusions and Relevance: In this contemporary study of on-pump CABG, we did not identify any significant differences in the incidence of postoperative stroke regardless of the clamping method used to perform proximal anastomosis.

Background: Transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) are treatment options for aortic stenosis in patients with prior coronary artery bypass graft surgery. We assessed the major clinical outcomes of such patients enrolled in the CoreValve High Risk (CHR) study., Methods: Of the 795 CHR study patients, 226 had prior coronary artery bypass graft surgery; 115 underwent TAVR and 111 underwent SAVR. The primary endpoint was a comparison of all-cause mortality at 1 year. Important secondary clinical endpoints were assessed., Results: At 1 year, all-cause mortality was 9.6% for TAVR versus 18.1% for SAVR (p = 0.06); cardiovascular mortality was 7.0% for TAVR versus 13.8% for SAVR (p = 0.09). A combination of The Society of Thoracic Surgeons risk score greater than 7 and age greater than 80 years was a significant predictor of mortality, with TAVR demonstrating a survival advantage (p = 0.03). No differences were seen for stroke. The SAVR group had longer intensive care unit and hospital stays, increased incidence of acute kidney injury, life-threatening or disabling bleeding, and major adverse cardiac and cerebrovascular events (p < 0.05). Pacemaker implantation and paravalvular regurgitation were greater with TAVR at all timepoints., Conclusions: For patients with prior coronary artery bypass graft surgery and aortic stenosis, TAVR offers a significant morbidity advantage and a strong trend toward improved survival over SAVR at 1 year., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The Society of Thoracic Surgeons (STS) quality benchmarks guide clinical outcome improvement in cardiac surgery. Failure to rescue (FTR) from postoperative morbidity is a proposed metric of program quality. We examined the effect of a quality improvement initiative guided by STS quality measures on outcomes and FTR., Methods: Prospectively collected STS data on 3,065 consecutive patients who underwent nonemergency cardiac operations at a single institution from January 1, 2010, to January 31, 2014, were retrospectively analyzed. On January 1, 2012, the quality improvement initiative was implemented. Clinical outcomes and FTR rates were compared between operations performed before (group A) and after (group B) implementation., Results: STS predicted preoperative mortality and composite of mortality plus morbidity were similar in group A and group B (2.9% ± 3.7% vs 3.1% ± 4.0%, p = 0.21; 17.8% ± 12.1% vs 18.3% ± 12.4%, p = 0.24, respectively). However, the observed mortality and composite mortality plus morbidity were lower in group B vs group A (31 of 1,576 [2.0%] vs 46 of 1,489 [3.1%], p = 0.05; 168 of 1,576 [10.7%] vs 301 of 1,489 [20.2%], p = 0.0001, respectively). Despite clinical outcome improvement, no differences in FTR rates were observed across all seven major morbidity indicators in group A vs B (35 of 290 [12.1%] vs 19 of 156 [12.1%], p = 1.00, respectively). The finding of similarity in the FTR rate remained consistent during procedural subgroup analysis for isolated coronary artery bypass grafting in group A vs B (22 of 174 [12.6%] vs 9 of 77 [11.7%], p = 1.00, respectively)., Conclusions: Implementation of quality improvement initiatives significantly improves outcomes without affecting FTR rates. Further study is needed to determine if FTR provides additive value to quality assessment over existing STS metrics., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: We reported favorable 1-year outcomes in patients unsuitable for surgery who underwent self-expanding transcatheter aortic valve replacement (TAVR) compared with an objective performance goal. Longer-term outcomes in these patients are not known., Objectives: This study sought to evaluate the 2-year safety and efficacy in patients with severe aortic stenosis (AS) at extreme risk of surgery treated with self-expanding TAVR., Methods: We performed a prospective, multicenter, controlled, nonrandomized investigation of self-expanding TAVR in patients with severe AS and prohibitive surgical risk. We report the 2-year clinical outcomes in these patients., Results: A total of 489 extreme-risk patients were treated transfemorally with a self-expanding aortic bioprosthesis at 41 centers. The rate of all-cause mortality or major stroke was 38.0% at 2 years (all-cause mortality, 36.5%; major stroke, 5.1%). The rates of all-cause mortality, cardiovascular mortality, and major stroke were 36.6%, 26.2%, and 5.1%, respectively, at 2 years. Between 1 and 2 years, the incremental all-cause mortality, cardiovascular mortality, and major stroke rates were 12.3%, 7.9%, and 0.8%, respectively. Multivariable predictors of all-cause mortality at 2 years included the presence of coronary artery disease and admission from an assisted living center. A Society of Thoracic Surgeons score >15% was also predictive of 2-year all-cause mortality. At 2 years, 94% of patients had New York Heart Association functional class I or II symptoms. The frequency of moderate or severe paravalvular regurgitation (4.3% at 1 year; 4.4% at 2 years) was unchanged between the first and second year., Conclusions: Patients with severe AS at extreme surgical risk treated with self-expanding TAVR continued to show good clinical outcomes and hemodynamic valve performance at 2 years. The presence of comorbid conditions rather than valve performance affected 2-year outcomes in these patients. (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902)., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: The U.S. pivotal trial for the self-expanding valve found that among patients with severe aortic stenosis at increased risk for surgery, the 1-year survival rate was 4.9 percentage points higher in patients treated with a self-expanding transcatheter aortic valve bioprosthesis than in those treated with a surgical bioprosthesis., Objectives: Longer-term clinical outcomes were examined to confirm if this mortality benefit is sustained., Methods: Patients with severe aortic stenosis who were at increased surgical risk were recruited. Eligible patients were randomly assigned in a 1:1 ratio to transcatheter aortic valve replacement with the self-expanding transcatheter valve (transcatheter aortic valve replacement [TAVR] group) or to aortic valve replacement with a surgical bioprosthesis (surgical group). The 2-year clinical and echocardiographic outcomes were evaluated in these patients., Results: A total of 797 patients underwent randomization at 45 centers in the United States. The rate of 2-year all-cause mortality was significantly lower in the TAVR group (22.2%) than in the surgical group (28.6%; log-rank test p < 0.05) in the as-treated cohort, with an absolute reduction in risk of 6.5 percentage points. Similar results were found in the intention-to-treat cohort (log-rank test p < 0.05). The rate of 2-year death or major stroke was significantly lower in the TAVR group (24.2%) than in the surgical group (32.5%; log-rank test p = 0.01)., Conclusions: In patients with severe aortic stenosis who are at increased surgical risk, the higher rate of survival with a self-expanding TAVR compared with surgery was sustained at 2 years. (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902)., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: Acute type B aortic dissection (ABAD) can lead to visceral malperfusion, a potentially life-threatening complication. The purpose of this study was to investigate the presentation, management, and outcomes of ABAD patients with visceral ischemia who are enrolled in the International Registry of Acute Aortic Dissection., Methods: Patients with ABAD enrolled in the registry between 1996 and 2013 were identified and stratified based on presence of visceral ischemia at admission. Demographics, medical history, imaging results, management, and outcomes were compared for patients with versus without visceral ischemia., Results: A total of 1456 ABAD patients were identified, of which 104 (7.1%) presented with visceral ischemia. Preoperative limb ischemia (28% vs 7%, P < .001) and acute renal failure (41% vs 14%, P < .001) were more common among patients with visceral ischemia. Endovascular treatment and surgery were offered to 49% and 30% of the visceral ischemia cohort, respectively; remaining patients were managed conservatively. The in-hospital mortality was 30.8% for patients with visceral ischemia and 9.1% for those without visceral ischemia (odds ratio [OR] 4.44; 95% confidence interval [CI], 2.8-7.0, P < .0001). Mortality rates were similar after surgical and endovascular management of visceral ischemia (25.8% and 25.5%, respectively, P = not significant). Among the visceral ischemia group, medical management was a predictor of mortality in multivariate analysis (OR, 5.91; 95% CI, 1.2-31.0; P = .036)., Conclusions: Patients with ABAD complicated by visceral ischemia have a high risk of mortality. We observed similar outcomes for patients treated by endovascular management versus surgery, whereas medical management was an independent predictor of mortality. Early diagnosis and intervention for visceral ischemia seems to be crucial., (Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

We recently reported a mechanistic model to link micro-architectural information to the delamination strength (Sd) of human ascending thoracic aorta (ATA). That analysis demonstrated that the number density (N) and failure energy (Uf) of the radially-oriented collagen fibers contribute to the Sd of both aneurysmal (ATAA) and non-aneurysmal (CTRL-ATA) aortic tissue. Among the set of ATAA samples, we studied specimens from patients displaying bicuspid (BAV) and tricuspid aortic valve (TAV) morphologic phenotypes. Results from our prior work were based on the assumption that the Uf was independent of dissection direction. In the current study, we excluded that assumption and hypothesized that Uf correlates with the Sd of ATAA. To test the hypothesis, we used previously-reported experimentally-determined Sd measurements and N of radially-oriented collagen fibers as input in our validated mechanistic model to calculate Uf for BAV-ATAA, TAV-ATAA and CTRL-ATA tissue specimens. The results of our analysis revealed that Uf is significantly lower for both BAV-ATAA and TAV-ATAA compared to CTRL-ATA cases, and does not differ between BAV-ATAA and TAV-ATAA. Furthermore, we found that Uf is consistent between circumferential-radial and longitudinal-radial planes in either of BAV-ATAA, TAV-ATAA or CTRL-ATA specimens. These findings employ a novel mechanistic model to increase our understanding of the putative interrelationship between biomechanical properties, extracellular matrix biology, and failure energy of aortic dissection., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objectives: The CoreValve Extreme Risk US Pivotal Trial enrolled patients with symptomatic severe aortic stenosis deemed unsuitable for surgical aortic valve replacement. Implants were attempted using transfemoral access (n = 489) or an alternative access (n = 150). In present analysis, we sought to examine the safety and efficacy of CoreValve transcatheter aortic valve replacement using alternative access., Methods: The present study included 150 patients with prohibitive iliofemoral anatomy who were treated with the CoreValve transcatheter heart valve delivered by way of the subclavian artery (n = 70) or a direct aortic approach (n = 80). The echocardiograms were read by an independent core laboratory. The primary endpoint was all-cause mortality or major stroke at 12 months., Results: The preoperative aortic valve area was 0.72 ± 0.27 cm(2) and mean aortic valve gradient was 49.5 ± 17.0 mm Hg. After the transcatheter aortic valve replacement, the effective aortic valve area was 1.82 ± 0.64 cm(2) at 1 month and 1.85 ± 0.51 cm(2) at 12 months. The mean aortic valve gradient was 9.7 ± 5.8 mm Hg at 30 days and 9.5 ± 5.7 mm Hg at 12 months. The death or major stroke rate was 15.3% at 30 days and 39.4% at 12 months. The individual rate of all-cause mortality and major stroke was 11.3% and 7.5% at 30 days and 36.0% and 9.1% at 12 months., Conclusions: These data demonstrate that the CoreValve transcatheter heart valve delivered by an alternative access provides a suitable alternative for treatment of extreme risk patients with symptomatic severe aortic stenosis, who have prohibitive iliofemoral anatomy and no surgical options., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objective: An anterior cusp with a median raphe and false commissure is the most common bicuspid aortic valve phenotype. The cusp is typically restricted and its annular attachment malpositioned, often resulting in significant aortic regurgitation. A novel valve repair strategy was designed to create a symmetric valve to improve both function and durability., Methods: The technique involves converting the valve into a "symmetric" bicuspid valve by resection of the median raphe, with shortening of the anterior cusp's leading edge; resection of the false commissure with complete anterior annular detachment; enlargement, reinforcement, and translocation of the anterior cusp deeper into the left ventricular outflow tract; and valve-sparing aortic root replacement with concomitant annuloplasty., Results: A total of 32 patients with a bicuspid valve, aortic insufficiency, and aortic dilatation have undergone valve repair with root replacement. No operative deaths or strokes occurred, and no permanent pacemakers were required. Thirteen patients underwent complete conversion from "raphe'd" to "symmetric" morphology; the others underwent less complex repairs without translocation. The postoperative transvalvular gradients remained normal. Freedom from grade >1+ aortic regurgitation and valve-related reoperation was 100%. All 13 symmetric conversion patients have continued to have no or trace aortic regurgitation (grade < 1+) at a mean follow-up of 2.9 years (range, 0.4-7)., Conclusions: Repair of the common, "raphe'd" bicuspid phenotype by reconfiguration into "symmetric" morphology is both feasible and desirable, regardless of the degree of preoperative aortic regurgitation. This repair strategy appears durable at the mid-term without evolving signs of deterioration or stenosis, offering a potentially superior option over prosthetic root replacement for younger patients., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to evaluate the safety and efficacy of the CoreValve transcatheter heart valve (THV) for the treatment of severe aortic stenosis in patients at extreme risk for surgery., Background: Untreated severe aortic stenosis is a progressive disease with a poor prognosis. Transcatheter aortic valve replacement (TAVR) with a self-expanding bioprosthesis is a potentially effective therapy., Methods: We performed a prospective, multicenter, nonrandomized investigation evaluating the safety and efficacy of self-expanding TAVR in patients with symptomatic severe aortic stenosis with prohibitive risks for surgery. The primary endpoint was a composite of all-cause mortality or major stroke at 12 months, which was compared with a pre-specified objective performance goal (OPG)., Results: A total of 41 sites in the United States recruited 506 patients, of whom 489 underwent attempted treatment with the CoreValve THV. The rate of all-cause mortality or major stroke at 12 months was 26.0% (upper 2-sided 95% confidence bound: 29.9%) versus 43.0% with the OPG (p < 0.0001). Individual 30-day and 12-month events included all-cause mortality (8.4% and 24.3%, respectively) and major stroke (2.3% and 4.3%, respectively). Procedural events at 30 days included life-threatening/disabling bleeding (12.7%), major vascular complications (8.2%), and need for permanent pacemaker placement (21.6%). The frequency of moderate or severe paravalvular aortic regurgitation was lower 12 months after self-expanding TAVR (4.2%) than at discharge (10.7%; p = 0.004 for paired analysis)., Conclusions: TAVR with a self-expanding bioprosthesis was safe and effective in patients with symptomatic severe aortic stenosis at prohibitive risk for surgical valve replacement. (Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement; NCT01240902)., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: We compared transcatheter aortic-valve replacement (TAVR), using a self-expanding transcatheter aortic-valve bioprosthesis, with surgical aortic-valve replacement in patients with severe aortic stenosis and an increased risk of death during surgery., Methods: We recruited patients with severe aortic stenosis who were at increased surgical risk as determined by the heart team at each study center. Risk assessment included the Society of Thoracic Surgeons Predictor Risk of Mortality estimate and consideration of other key risk factors. Eligible patients were randomly assigned in a 1:1 ratio to TAVR with the self-expanding transcatheter valve (TAVR group) or to surgical aortic-valve replacement (surgical group). The primary end point was the rate of death from any cause at 1 year, evaluated with the use of both noninferiority and superiority testing., Results: A total of 795 patients underwent randomization at 45 centers in the United States. In the as-treated analysis, the rate of death from any cause at 1 year was significantly lower in the TAVR group than in the surgical group (14.2% vs. 19.1%), with an absolute reduction in risk of 4.9 percentage points (upper boundary of the 95% confidence interval, -0.4; P<0.001 for noninferiority; P = 0.04 for superiority). The results were similar in the intention-to-treat analysis. In a hierarchical testing procedure, TAVR was noninferior with respect to echocardiographic indexes of valve stenosis, functional status, and quality of life. Exploratory analyses suggested a reduction in the rate of major adverse cardiovascular and cerebrovascular events and no increase in the risk of stroke., Conclusions: In patients with severe aortic stenosis who are at increased surgical risk, TAVR with a self-expanding transcatheter aortic-valve bioprosthesis was associated with a significantly higher rate of survival at 1 year than surgical aortic-valve replacement. (Funded by Medtronic; U.S. CoreValve High Risk Study ClinicalTrials.gov number, NCT01240902.).

The aorta possesses a micro-architecture that imparts and supports a high degree of compliance and mechanical strength. Alteration of the quantity and/or arrangement of the main load-bearing components of this micro-architecture--the elastin and collagen fibers--leads to mechanical, and hence functional, changes associated with aortic disease and aging. Therefore, in the future, the ability to rigorously characterize the wall fiber micro-architecture could provide insight into the complicated mechanisms of aortic wall remodeling in aging and disease. Elastin and collagen fibers can be observed using state-of-the-art multi-photon microscopy. Image-analysis algorithms have been effective at characterizing fibrous constructs using various microscopy modalities. The objective of this study was to develop a custom MATLAB-language automated image-based analysis tool to describe multiple parameters of elastin and collagen micro-architecture in human soft fibrous tissue samples using multi-photon microscopy images. Human aortic tissue samples were used to develop the code. The tool smooths, cleans and equalizes fiber intensities in the image before segmenting the fibers into a binary image. The binary image is cleaned and thinned to a fiber skeleton representation of the image. The developed software analyzes the fiber skeleton to obtain intersections, fiber orientation, concentration, porosity, diameter distribution, segment length and tortuosity. In the future, the developed custom image-based analysis tool can be used to describe the micro-architecture of aortic wall samples in a variety of conditions. While this work targeted the aorta, the software has the potential to describe the architecture of other fibrous materials, tube-like networks and connective tissues., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Aortic dissection (AoD) is a common condition that often leads to life-threatening cardiovascular emergency. From a biomechanics viewpoint, AoD involves failure of load-bearing microstructural components of the aortic wall, mainly elastin and collagen fibers. Delamination strength of the aortic wall depends on the load-bearing capacity and local micro-architecture of these fibers, which may vary with age, disease and aortic location. Therefore, quantifying the role of fiber micro-architecture on the delamination strength of the aortic wall may lead to improved understanding of AoD. We present an experimentally-driven modeling paradigm towards this goal. Specifically, we utilize collagen fiber micro-architecture, obtained in a parallel study from multi-photon microscopy, in a predictive mechanistic framework to characterize the delamination strength. We then validate our model against peel test experiments on human aortic strips and utilize the model to predict the delamination strength of separate aortic strips and compare with experimental findings. We observe that the number density and failure energy of the radially-running collagen fibers control the peel strength. Furthermore, our model suggests that the lower delamination strength previously found for the circumferential direction in human aorta is related to a lower number density of radially-running collagen fibers in that direction. Our model sets the stage for an expanded future study that could predict AoD propagation in patient-specific aortic geometries and better understand factors that may influence propensity for occurrence., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Objectives: Patients with bicuspid aortic valves (BAV) are predisposed to developing ascending thoracic aortic aneurysms (TAA) at an earlier age than patients who develop degenerative TAAs and have a tricuspid aortic valve (TAV). The hypothesis tested is that BAV-associated aortopathy is mediated by a mechanism of matrix remodeling that is distinct from that seen in TAAs of patients with tricuspid aortic valves., Methods: Aortic specimens were collected during ascending aortic replacement, aortic valve replacement, and heart transplants from nonaneurysmal (NA) donors and recipients. Matrix architecture of the aortic media was assessed qualitatively using multiphoton microscopy followed by quantification of collagen and elastin fiber orientation. α-Elastin was determined and matrix maturity was assessed by quantifying immature and mature collagen and lysyl oxidase (Lox) expression and activity in aortic specimens. Matrix metalloproteinase-2/9 activity was quantified in aortic smooth muscle cells., Results: Elastin and collagen fibers were more highly aligned in BAV-NA and BAV-TAA cases than in TAV-TAA cases, whereas TAV-TAA cases were more disorganized than TAV-NA cases. α-Elastin content was unchanged. Immature collagen was reduced in BAV-NA and BAV-TAA cases when compared with TAV-NA and TAV-TAA cases. Mature collagen was elevated in TAV-TAA cases compared with TAV-NA and BAV-TAA cases. There was a trend toward elevated Lox gene expression and activity and matrix metalloproteinase-2/9 activity for TAV-TAA, BAV-NA, and BAV-TAA specimens., Conclusions: The highly aligned matrix architecture in patients with BAVs indicates that wall remodeling is distinct from TAV-TAA. Altered matrix architecture and reduced collagen maturity suggest that the effector molecules mediating the remodeling of TAAs are different in BAV and TAV cases., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Background: Ascending thoracic aortic aneurysm (ATAA) predisposes patients to aortic dissection and has been associated with diminished tensile strength and disruption of collagen. Ascending thoracic aortic aneurysms arising in patients with bicuspid aortic valve (BAV) develop earlier than in those with tricuspid aortic valves (TAV) and have a different risk of dissection. The purpose of this study was to compare aortic wall tensile strength between BAV and TAV ATAAs and determine whether the collagen content of the ATAA wall is associated with tensile strength and valve phenotype., Methods: Longitudinally and circumferentially oriented strips of ATAA tissue obtained during elective surgery were stretched to failure, and collagen content was estimated by hydroxyproline assay. Experimental stress-strain data were analyzed for failure strength and elastic mechanical variables: α, β, and maximal tangential stiffness., Results: The circumferential and longitudinal tensile strengths were higher for BAV ATAAs when compared with TAV ATAAs. The α and β were lower for BAV ATAAs when compared with TAV ATAAs. The maximal tangential stiffness was higher for circumferential when compared with longitudinal orientation in both BAV and TAV ATAAs. The amount of hydroxyproline was equivalent in BAV and TAV ATAA specimens. Although there was a moderate correlation between the collagen content and tensile strength for TAV, this correlation is not present in BAV., Conclusions: The increased tensile strength and decreased values of α and β in BAV ATAAs despite uniform collagen content between groups indicate that microstructural changes in collagen contribute to BAV-associated aortopathy., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

It was recently demonstrated by our group that the delamination strength of ascending thoracic aortic aneurysms (ATAA) was lower than that of control (CTRL, non-aneurysmal) ascending thoracic aorta (ATA), and the reduced strength was more pronounced among bicuspid (BAV) vs. tricuspid aortic valve (TAV) patients, suggesting a different risk of aortic dissection for BAV patients. We hypothesized that aortic valve morphologic phenotype predicts fiber micro-architectural anomalies in ATA. To test the hypothesis, we characterized the micro-architecture in the longitudinal-radial (Z-RAD) and circumferential-radial (Θ-RAD) planes of human ATA tissue that was artificially dissected medially. The outer and inner-media of CTRL-ATA, BAV-ATAA and TAV-ATAA were imaged using multi-photon microscopy in the Z-RAD and Θ-RAD planes to observe collagen and elastin. Micrographs were processed using an image-based tool to quantify several micro-architectural characteristics. In the outer-media of BAV-ATAA, elastin was more undulated and less aligned about the Θ-axis when compared with CTRL-ATA, which is consistent with increased tensile stretch at inflection point of Θ-strips of adventitial-medial half of BAV-ATAA (1.28) when compared with CTRL-ATA (1.13). With increasing age, collagen became more undulated about the Z-axis within the outer-media of TAV-ATAA, and elastin became more oriented in the Z-axis and collagen less radially-oriented within the inner-media of TAV-ATAA. This discrepancy in the micro-architecture with fibers in the inner layers being more stretched and with disrupted radially-oriented components than fibers in the outer layers may be associated with the development, progression and vascular remodeling in aneurysms arising in TAV patients., (© 2013 Elsevier Ltd. All rights reserved.)

The aortic dissection (AoD) of an ascending thoracic aortic aneurysm (ATAA) initiates when the hemodynamic loads exerted on the aneurysmal wall overcome the adhesive forces holding the elastic layers together. Parallel coupled, two-way fluid-structure interaction (FSI) analyses were performed on patient-specific ATAAs obtained from patients with either bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) to evaluate hemodynamic predictors and wall stresses imparting aneurysm enlargement and AoD. Results showed a left-handed circumferential flow with slower-moving helical pattern in the aneurysm's center for BAV ATAAs whereas a slight deviation of the blood flow toward the anterolateral region of the ascending aorta was observed for TAV ATAAs. Blood pressure and wall shear stress were found key hemodynamic predictors of aneurysm dilatation, and their dissimilarities are likely associated to the morphological anatomy of the aortic valve. We also observed discontinues, wall stresses on aneurysmal aorta, which was modeled as a composite with two elastic layers (i.e., inhomogeneity of vessel structural organization). This stress distribution was caused by differences on elastic material properties of aortic layers. Wall stress distribution suggests AoD just above sinotubular junction. Moreover, abnormal flow and lower elastic material properties that are likely intrinsic in BAV individuals render the aneurysm susceptible to the initiation of AoD., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objective: This was a single-center retrospective study to assess the surgical outcomes and predictors of mortality of liver transplant recipients undergoing cardiac surgery., Methods: From 2000 to 2010, 61 patients with a functioning liver allograft underwent cardiac surgery. The mean interval between liver transplantation and cardiac surgery was 5.4 ± 4.4 years. Of the 61 patients, 33 (54%) were in Child-Pugh class A and 28 in class B. The preoperative and postoperative data were reviewed., Results: The overall in-hospital mortality was 6.6%. The survival rate was 82.4% ± 5.1% at 1 year and 50.2% ± 8.2% at 5 years. Cox regression analysis identified preoperative encephalopathy (odds ratio, 5.2; 95% confidence interval, 1.8-15.5; P = .003) and pulmonary hypertension (odds ratio, 3.5; 95% confidence interval, 1.3-9.4; P = .045) as independent predictors of late mortality. The preoperative Model for End-Stage Liver Disease (MELD) scores of patients who died in-hospital or late postoperatively were significantly greater statistically than the scores of the others (in-hospital death, 23.7 ± 7.8 vs 13.1 ± 4.5, P < .001; late death, 15.2 ± 6.1 vs 12.3 ± 4.1, P = .038). The Youden index identified an optimal MELD score cutoff value of 13.5 (sensitivity, 56.0%; specificity, 67.6%). Kaplan-Meier survival analysis successfully demonstrated that the survival rate of the MELD score less than 13.5 (MELD <13.5) group was significantly greater than that of the MELD >13.5 group (MELD <13.5 group, 93.8% ± 4.2% at 1 year and 52.4% ± 11.8% at 5 years; MELD >13.5 group, 66.9% ± 9.6% at 1 year and 46.1% ± 11.1% at 5 years; P = .027). In contrast, the survival rate when stratified by Child-Pugh class (class A vs B) was not significantly different., Conclusions: Cardiac surgery in the liver allograft recipients was associated with acceptable surgical outcomes. Preoperative encephalopathy and pulmonary hypertension were independent predictors of late mortality. The cutoff value of 13.5 in the MELD score might be useful for predicting surgical mortality in cardiac surgery., (Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

Objectives: The acute dissection of an ascending thoracic aortic aneurysm (ATAA) represents a devastating separation of elastic layers occurring when the hemodynamic loads on the diseased wall exceed the adhesive strength between layers. At present, the mechanics underlying aortic dissection are largely unclear, and the biomechanical delamination properties of the aneurysmal aorta are not defined. Individuals with bicuspid aortic valve (BAV) are particularly predisposed to ascending aortic aneurysm formation, with a marked risk of aortic dissection. The purpose of this study was to evaluate and compare the dissection properties of nonaneurysmal and aneurysmal human ascending thoracic aorta from patients with BAV morphology or normal tricuspid aortic valve (TAV) morphology using biomechanical delamination testing., Methods: The influence on the delamination strength (S(d)) of the aorta associated with BAV was compared with that in patients with TAV. After complete delamination of ATAA tissue samples, tensile tests were performed on each delaminated half for comparison of their tensile strengths., Results: The results showed that the aneurysmal aortas with BAV and TAV have lower S(d) than nonaneurysmal aortas and that ATAA with BAV has a lower S(d) than that with TAV. We have found a significant difference in S(d) between longitudinal and circumferential directions of the nondiseased aorta, suggesting anisotropic dissection properties., Conclusions: The tensile testing results suggest that the weaker intimal half of the aortic wall might fail before the outer adventitial half. Scanning electron microscope analyses suggest different failure modalities of dissection between the two morphologies, and the lower S(d) in ATAAs appears to be associated with a disorganized microstructure. BAV ATAAs have a lower S(d) than TAV ATAAs, suggesting a greater propensity for aortic dissection., (Published by Mosby, Inc.)

Background: Surgical treatment for endocarditis is still challenging and only a handful of studies have analyzed surgical outcomes in patients with active multivalvular endocarditis., Methods: From June 1996 to October 2007, 152 patients underwent surgery for active native valve endocarditis; 117 patients with single-valve endocarditis and 35 patients with multivalvular endocarditis. Preoperative and postoperative data were retrospectively reviewed to determine risk factors for early and late mortality., Results: One-year and 5-year survival were 78.6%±3.8% and 54.8%±5.3% in the single-valve group, and 74.3%±7.4% and 64.8%±8.3% in the multivalve group, respectively (log-rank 0.64). The rates of valve replacement were significantly higher in the single-valve group than in the multivalve group in all sites except the pulmonary valve. Freedom from reoperation was 90.0%±3.6% in the single-valve group and 79.5%±8.5% in the multivalve group in 5 years (log-rank 0.30). No recurrence of endocarditis was noted in the multivalve group, while 4 patients (3.4%) had recurrence in the single-valve group during the follow-up period (p=0.57). There was no significant difference in postoperative complications between the two groups. Multivariate analysis of the multivalve group identified postoperative renal failure as a predictor of late mortality with no predictors identified for early mortality, reoperation, and recurrence. Statistical analysis of the overall cohorts showed multivalve endocarditis was not an independent predictor of early and late mortality., Conclusions: Surgical treatment for active, native, and noncomplicated multivalve endocarditis was associated with respectable early and late morbidity and mortality comparable with single-valve endocarditis, and was not an independent predictor of early and late mortality., (Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The mechanisms governing extracellular matrix degradation and smooth muscle cell (SMC) loss in the ascending aorta of bicuspid aortic valve (BAV) patients are unknown. We recently reported that expression and induction of metallothionein, a reactive oxygen species scavenger, is reduced in BAV ascending aortic aneurysms relative to nonaneurysmal patients., Methods: Tissue and primary SMCs from patients with and without thoracic aortic aneurysms and metallothionein-null and wild-type mice were analyzed for cell viability, vascular endothelial growth factor (VEGF), and type I collagen gene expression during exposure to reactive oxygen species., Results: The BAV SMCs and metallothionein -/- mice failed to induce VEGF under conditions of oxidative stress in vitro. Exogenous VEGF restored resistance to oxidative stress in BAV SMCs to normal. Type I collagen gene induction was increased in BAV aorta., Conclusions: Lack of VEGF induction during exposure to reactive oxygen species suggest that the oxidative stress response is faulty upstream of metallothionein and VEGF in BAV SMCs. Improvement of cell viability with VEGF treatment suggests that the deficient pathway can be rescued by VEGF. Increased type I collagen in BAV suggests that lack of metallothionein/VEGF activation in response to reactive oxygen species may play a role in extracellular matrix homeostasis of the ascending aorta. These data continue to support our hypothesis that BAV SMCs lack sufficient resistance to reactive oxygen species to maintain extracellular matrix homeostasis, which imparts a predisposition to thoracic aortic aneurysms., (Copyright © 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Endoleaks and endotension remain the primary limitation of endovascular aortic repair with stent-grafts. Consequently, all endovascular surgeons performing thoracic or abdominal endovascular aortic repairs require a comprehensive knowledge and understanding of how to survey and manage endoleaks. The derivation of the current endoleak classification scheme, the clinical impact of endoleaks, the diagnostic tools relevant to endoleak detection, an endoleak surveillance protocol, and the strategies in use for their management are outlined in this review., (Copyright 2009 Elsevier Inc. All rights reserved.)

Thoracic great vessel and cardiac trauma are characterized by anatomic location and mechanism of injury: blunt or penetrating. Management strategies are also directed by the extent and mechanism of injury. Advances in imaging and catheter-based technologies have allowed easier and more accurate diagnosis and less-invasive treatments. Although the advantages of endovascular techniques are attractive, open surgical repair remains the definitive treatment for many of these thoracic injuries. Given the increasing sophistication of these technologies and the demonstrated usefulness of a disease-oriented approach toward patient management, trauma centers have adopted a multidisciplinary team model for management of multitrauma victims. In this review, the authors detail the diagnosis and management of blunt aortic, nonaortic great vessel, blunt cardiac, and penetrating cardiac injuries.