Optimal circulatory arrest temperature for aortic hemiarch replacement with antegrade brain perfusion.

OBJECTIVE: This study sought to identify the optimal temperature for moderate hypothermic circulatory arrest in patients undergoing elective hemiarch replacement with antegrade brain perfusion. METHODS: The Society of Thoracic Surgeons adult cardiac surgery database was queried for elective hemiarch replacements using antegrade brain perfusion for aneurysmal disease (2014-2019). Generalized estimating equations and restricted cubic splines were used to determine the risk-adjusted relationships between temperature as a continuous variable and outcomes. RESULTS: Elective hemiarch replacement with antegrade brain perfusion occurred in 3898 patients at 374 centers with a median nadir temperature of 24.9°C (first quartile, third quartile = 22.0°C, 27.5°C) and median circulatory arrest time of 19 minutes (first quartile, third quartile = 14.0 minutes, 27.0 minutes). After adjustment for comorbidities, circulatory arrest time, and individual surgeon, patients cooled between 25 and 28°C had an early survival advantage compared with 24°C, whereas those cooled between 21 and 23°C had higher risks of mortality compared with 24°C. A nadir temperature of 27°C was associated with the lowest risk-adjusted odds of mortality (odds ratio, 0.62; 95% confidence interval, 0.42-0.91). A nadir temperature of 21°C had the highest risk of mortality (odds ratio, 1.4; 95% confidence interval, 1.13-1.73). Risk of experiencing a major morbidity was elevated in patients cooled between 21 and 23°C, with the highest risk occurring in patients cooled to 21°C (odds ratio, 1.12; 95% confidence interval, 1.01-1.24). CONCLUSIONS: For patients with aneurysmal disease undergoing elective hemiarch with antegrade brain perfusion, circulatory arrest with a nadir temperature of 27°C confers the greatest early survival benefit and smallest risk of postoperative morbidity.

The predictive capability of aortic stiffness index for aortic dissection among dilated ascending aortas.

OBJECTIVE: We created a finite element model to predict the probability of dissection based on imaging-derived aortic stiffness and investigated the link between stiffness and wall tensile stress using our model. METHODS: Transthoracic echocardiogram measurements were used to calculate aortic diameter change over the cardiac cycle. Aortic stiffness index was subsequently calculated based on diameter change and blood pressure. A series of logistic models were developed to predict the binary outcome of aortic dissection using 1 or more series of predictor parameters such as aortic stiffness index or patient characteristics. Finite element analysis was performed on a subset of diameter-matched patients exhibiting patient-specific material properties. RESULTS: Transthoracic echocardiogram scans of patients with type A aortic dissection (n = 22) exhibited elevated baseline aortic stiffness index when compared with aneurysmal patients' scans with tricuspid aortic valve (n = 83, P < .001) and bicuspid aortic valve (n = 80, P < .001). Aortic stiffness index proved an excellent discriminator for a future dissection event (area under the curve, 0.9337, odds ratio, 2.896). From the parametric finite element study, we found a correlation between peak longitudinal wall tensile stress and stiffness index (ρ = .6268, P < .001, n = 28 pooled). CONCLUSIONS: Noninvasive transthoracic echocardiogram-derived aortic stiffness measurements may serve as an impactful metric toward predicting aortic dissection or quantifying dissection risk. A correlation between longitudinal stress and stiffness establishes an evidence-based link between a noninvasive stiffness parameter and stress state of the aorta with clinically apparent dissection events.

The impact of acute kidney injury by serum creatinine or urine output criteria on major adverse kidney events in cardiac surgery patients.

OBJECTIVES: Oliguria after cardiac surgery remains of uncertain clinical significance. Therefore, we investigated the relationship of acute kidney injury severity across urine output and creatinine domains with the risk for major adverse kidney events at 180 days. We aimed to determine the impact of acute kidney injury after cardiac surgery. METHODS: In a retrospective multicenter study, we investigated the relationship of acute kidney injury severity across urine output and creatinine categories with the risk for major adverse kidney events at 180 days-the composite of death, dialysis, and persistent renal dysfunction-using a large database of patients undergoing cardiac surgery at 1 of 5 hospitals within the regional medical system. We analyzed electronic records from 6637 patients treated between 2008 and 2014, of whom 5389 (81.2%) developed any acute kidney injury within 72 hours of surgery. We stratified patients by levels of urine output or serum creatinine according to Kidney Disease Improving Global Outcomes criteria for acute kidney injury. RESULTS: Major adverse kidney events at 180 days increased from 4.5% for no acute kidney injury to 61.3% for stage 3 acute kidney injury (P < .001). Death or dialysis by day 180 was 2.4% for those with no acute kidney injury and 46.7% for those with acute kidney injury stage 3 (P < .001). Isolated oliguria was common (42.6%), and isolated azotemia was rare (6.1%). Even stage 1 acute kidney injury by oliguria alone was associated with an increased risk of major adverse kidney events at 180 days (odds ratio, 1.76; 1.20-2.57; P = .004), mainly driven by persistent renal dysfunction (odds ratio, 2.01; 1.26-3.18; P = .003). CONCLUSIONS: Acute kidney injury is common in patients undergoing cardiac surgery, and even milder forms of acute kidney injury, including isolated stage 1 oliguria, are associated with adverse long-term consequences.

Timing of coronary artery bypass grafting after acute myocardial infarction may not influence mortality and readmissions.

OBJECTIVE: Coronary artery bypass grafting is often delayed after acute myocardial infarction to avoid an increase in postoperative morbidity and mortality. We hypothesized that the timing of coronary artery bypass grafting after acute myocardial infarction may not be consistently associated with postoperative outcomes. METHODS: All patients who underwent isolated coronary artery bypass grafting at the University of Pittsburgh Medical Center from 2011 to 2017 after an acute myocardial infarction were reviewed. A comparative analysis for time from myocardial infarction presentation to coronary artery bypass grafting was performed with primary outcomes including all-cause mortality and readmission. RESULTS: A total of 7048 patients underwent isolated coronary artery bypass grafting. Of these, 2058 patients had acute myocardial infarction with all relevant variables available for analysis. The study population was divided into 2 coronary artery bypass grafting timing cohorts, including less than 24 hours (n = 292) and 24 hours or more (n = 1766). Previous percutaneous coronary intervention, cardiogenic shock, and intra-aortic balloon pump were more prevalent in the less than 24 hours group. Operative mortality was significantly higher in the less than 24 hours cohort (7.19% vs 3.79%; P = .01). Diabetes mellitus, peripheral vascular disease, serum creatinine, age, chronic obstructive pulmonary disease, and immunosuppression were significant predictors (P < .05) of mortality. After risk adjustment with propensity scoring, there was no difference between time cohorts for operative mortality (4.15% vs 4.58%; P = .62). New-onset atrial fibrillation occurred more frequently in the 24 hours or more cohort. There was no difference between groups for the occurrence of major adverse cardiovascular and cerebrovascular event readmissions. CONCLUSIONS: After adjusting for baseline patient characteristics, there was no statistically significant difference between timing cohorts for mortality or major adverse cardiovascular and cerebrovascular event readmissions.

Percutaneous coronary intervention versus coronary artery bypass grafting in patients with reduced ejection fraction.

OBJECTIVE: The aim of this study was to evaluate comparative outcomes for percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) in patients with reduced ejection fraction. METHODS: All patients from the University of Pittsburgh Medical Center from 2011 to 2018 who had reduced preoperative ejection fraction (<50%) and underwent CABG or PCI for coronary revascularization were included in this study. Patients were risk-adjusted with propensity matching (1:1) and primary outcomes included long-term survival, readmission, and major adverse cardiac and cerebrovascular events (MACCE). RESULTS: A total of 2000 patients were included in the current study, consisting of CABG (n = 1553) and PCI (n = 447) cohorts with a mean ejection fraction of 35% ± 9.53%. Propensity matching yielded a 1:1 match with 324 patients in each cohort, controlling for all baseline characteristics. Thirty-day mortality was similar for PCI versus CABG (6.2% vs 4.9%; P = .49). Overall mortality over the study follow-up period (median, 3.23 years; range, 1.83-4.98 years) was significantly higher for the PCI cohort (37.4% vs 21.3%; P < .001). Total hospital readmissions (24.1% vs 12.9%; P = .001), cardiac readmissions (20.4% vs 11.1%; P = .001), myocardial infarction event (7.7% vs 1.8%; P = .001), MACCE (41.4% vs 23.8%; P < .001), and repeat revascularization (6.5% vs 2.6%; P = .02) occurred more frequently in the PCI cohort. Freedom from MACCE at 1 year (74.4% vs 87.0%; P < .001) and 5 years (54.5% vs 74.0%; P < .001) was significantly lower for the PCI cohort. On multivariable cox regression analysis, CABG (hazard ratio, 0.57; 95% confidence interval, 0.44-0.73; P < .001) was significantly associated with improved survival. Prior liver disease, dialysis, diabetes, and peripheral artery disease were the most significant predictors of mortality. The cumulative incidence of hospital readmission was lower for the CABG cohort (hazard ratio, 0.51; 95% confidence interval, 0.37-0.71; P < .001). Multivariable cox regression for MACCE (hazard ratio, 0.48; 95% confidence interval, 0.39-0.58; P < .001) showed significantly fewer events for the CABG cohort. CONCLUSIONS: Patients with reduced ejection fraction who underwent CABG had significantly improved survival, lower MACCE, and fewer repeat revascularization procedures compared with patients who underwent PCI.

Outcomes in patients with solid organ transplants undergoing cardiac surgery.

OBJECTIVE: Long-term outcomes after cardiac surgery in solid organ transplant recipients are limited in the contemporary literature. The objective of this study is to evaluate postoperative outcomes in these patients, including variables associated with mortality and readmissions. METHODS: All adults undergoing isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve cardiac surgical procedures from 2011 to 2018 were included in this study. Patients with solid organ transplants undergoing cardiac surgery were studied. Primary outcomes included operative (30-day) and 5-year mortality. RESULTS: A total of 11,190 patients underwent isolated coronary artery bypass grafting, isolated valve, or coronary artery bypass grafting + valve operations at our institution from 2011 to 2018. Of these, 129 patients (1%) had solid organ transplants and underwent isolated coronary artery bypass grafting (n = 84), isolated valve (n = 30), or coronary artery bypass grafting + valve (n = 15). Type of organ transplant included 84 patients (65%) with kidney, 27 patients (21%) with liver, 9 patients (7%) with heart, and 9 patients (7%) with lung transplants. The median Society of Thoracic Surgeons Predicted Risk Of Mortality for the cohort was 2.73 (Q1-Q3: 1.67-6.33). Three patients (2%) had an operative (30-day) mortality. Significant variables associated with 5-year mortality on multivariable Cox regression analysis included chronic obstructive pulmonary disease (hazard ratio, 2.44; 1.01-5.90; P = .048) and congestive heart failure (hazard ratio, 4.45; 1.81-10.9; P = .001). Significant variables associated with 5-year readmissions included chronic obstructive pulmonary disease, dialysis dependence, and concomittant valve surgery with coronary artery bypass grafting. Five-year readmission rate was 88%, and patients with valve operations (± coronary artery bypass grafting) had significantly lower (P = .009) freedom from readmission (6%). CONCLUSIONS: Cardiac surgery can be performed with low operative mortality and good long-term survival in patients with solid organ transplants. Five-year hospital readmissions are common, with significantly more readmissions in patients who had valve procedures.

Medical student perceptions of a career in cardiothoracic surgery: Results of an institutional survey.

OBJECTIVES: Recruiting medical students to cardiothoracic surgery is critical given new training paradigms and projected cardiothoracic surgeon shortages. This study characterizes current perceptions and exposure to cardiothoracic surgery among all levels of medical students. METHODS: Currently active medical students at all levels at a US allopathic medical school were sent an invitation to complete an online survey. Baseline demographics, medical specialty interest, interest and exposure to cardiac surgery specifically, and awareness of procedures performed by cardiothoracic surgeons were evaluated. Five-point Likert scales were used to evaluate attitudes toward facets of the field of cardiothoracic surgery. Only complete surveys over the 4-week enrollment period were used for analysis. RESULTS: There were 126 surveys (22%) completed during the study period. Interest in cardiothoracic surgery at any point was indicated by 37% of students, but only 13% indicated an interest at the time of the survey. Interest among first-year students was greater than all other classes (30% vs <15%, P = .02). Lifestyle factors and personal attributes of cardiothoracic surgeons were noted as negative factors influencing cardiothoracic surgery perception, whereas intellectual challenge and clinical impact were cited as positive factors. Increasing interaction with faculty/residents and simulation experiences were factors noted to increase interest in the field. CONCLUSIONS: Although medical students report early interest in cardiothoracic surgery because of intellectual stimulation and patient care attributes, lack of early exposure and perceived poor lifestyle negatively affect interest in the field. Early interaction between students and cardiothoracic faculty/trainees along with early exposure opportunities may increase recruitment.

Concomitant left subclavian artery revascularization with carotid-subclavian transposition during zone 2 thoracic endovascular aortic repair.

BACKGROUND: Left subclavian revascularization has become an integral part of thoracic endovascular aortic repair to extend the proximal landing zone. This is most commonly achieved via carotid-subclavian bypass; however, this can be achieved via vessel transposition. METHODS: All patients who had zone 2 thoracic endovascular aortic repairs without branched grafts from 2007 to 2018 were included in the study. The primary outcomes were adverse events, including operative mortality, paraplegia, left arm ischemia, and stroke. Multivariable regression analysis was performed for baseline characteristics associated with adverse events. RESULTS: A total of 58 patients underwent left subclavian artery transposition for zone 2 thoracic endovascular aortic repair coverage. Operative (30-day) mortality occurred in 3 patients (5.2%). The majority of patients were operated on under urgent (N = 25; 43.1%) or emergency (N = 12; 20.7%) status. Indications for thoracic endovascular aortic repair included aneurysmal disease (34.5%) and type B aortic dissection (chronic [13.8%]; acute [51.7%]). Major adverse events included paraplegia (N = 1; 1.7%), transient paraparesis (N = 3; 5.2%), and stroke (N = 2; 3.4%). Over a mean follow-up of 2.8 years, there were 5 deaths (8.6%). On multivariable analysis, prior stroke (odds ratio, 31.4; 1.95-506.72; P = .02) was an independent predictor of adverse events. CONCLUSIONS: Carotid-subclavian transposition offers patients a safe and effective method for left subclavian artery revascularization during thoracic endovascular aortic repair with zone 2 coverage with no increased operative risk and a low complication rate.

Off-Pump Coronary Artery Bypass Grafting: Closing the Communication Gap Across the Ether Screen.

Cardiopulmonary bypass (CPB) has been one of the most important additions to the field of heart surgery in the past century. However, significant morbidity associated with CPB has led to the increasing implementation of off-pump coronary artery bypass (OPCAB). The use of OPCAB has broadened surgical revascularization for patient populations at high risk for undergoing CPB, including the very elderly and patients with impending end-organ failure. Intraoperative hemodynamic instability requires expeditious correction of hypotension with various medical and surgical techniques that require the close attention and skill of both the anesthesia and surgical teams. Technical skill at performing and interpreting transesophageal echocardiography is essential to help differentiate regional wall motion abnormalities from coronary ischemia and external compression from manipulation of the heart, which require different management strategies to resolve hemodynamic collapse. Flawless communication between the anesthesiologist and surgeons, with frequent intraoperative adjustments, is paramount for the completion of successful OPCAB.

Distal Extent of Surgery for Acute Type A Aortic Dissection.

Acute type A aortic dissection (TAAD) is a complex disease associated with extremely high morbidity and mortality for which we advocate a coordinated, protocol-driven system of care delivery that begins at patient diagnosis and continues throughout and beyond aortic reconstruction. Essential components of TAAD repair include prompt restoration of true lumen blood flow with obliteration of the false lumen flow, resection of the primary tear sites, restoration of valvular competency, and elimination of any organ malperfusion. This article focuses specifically on extent of repair of the aortic arch and explains our protocols regarding cannulation location and technique, cerebral and distal organ protection strategy, management of the brachiocephalic vessels, and extent of distal aortic reconstruction. We describe an operative strategy for TAAD repair that includes (1) continuous neurocerebral monitoring in all cases, (2) uninterrupted antegrade and/or retrograde cerebral perfusion (depending upon extent of arch repair) during open arch reconstruction, (3) aortic arch replacement technique with or without brachiocephalic vessel replacement using a custom trifurcate graft, and (4) descending aortic stabilization with or without the use of an elephant or frozen elephant trunk (distal stent graft). Our protocol for extent of aortic arch and brachiocephalic reconstruction has been standardized and is predicated on distinct pathoanatomic findings and/or cerebral malperfusion that are outlined.

Open Surgical Access for Transfemoral TAVR Should Not Be a Contraindication for Conscious Sedation.

OBJECTIVES: The use of monitored anesthesia care (MAC) for transcatheter aortic valve replacement (TAVR) is gaining favor in the United States, although general anesthesia (GA) continues to be common for these procedures. Open surgical cutdown for transfemoral TAVR has been a relative contraindication for TAVR with MAC at most centers. The objective of this study was to review the authors' results of transfemoral TAVR performed in patients with open surgical cutdown with the use of MAC. DESIGN: Retrospective study design from a prospectively recorded database. SETTING: Tertiary academic (teaching) hospital. PARTICIPANTS: Two hundred eighty-two patients undergoing transfemoral TAVR with open surgical cutdown under MAC from 2015 to 2017. INTERVENTIONS: Transfemoral TAVR under MAC with surgical cutdown for femoral vascular access. MEASUREMENTS AND MAIN RESULTS: The study cohort consisted of 282 patients with severe aortic stenosis (mean area 0.65 [± 0.16] cm2, mean gradient of 48.9 [±13.3] mmHg, and mean age of 82.7 [± 7.31] years). Eleven (3.9%) patients required conversion to GA. First postoperative pain score (0-10) was 2.9 and highest postoperative pain score was 4.6. Major and minor vascular complications occurred in 2 (0.7%) and 6 (2.1%) patients, respectively. Twenty-nine (10.3%) patients were readmitted within 30 days, and 6 (2.1%) patients had in-hospital mortality. CONCLUSIONS: Open surgical cutdown for transfemoral TAVR can be performed safely using MAC and ilioinguinal block with low rates of conversion to general anesthesia and acceptable postoperative outcomes and pain scores.

Predissection-derived geometric and distensibility indices reveal increased peak longitudinal stress and stiffness in patients sustaining acute type A aortic dissection: Implications for predicting dissection.

OBJECTIVE: To assess ascending aortic distensibility and build geometry and distensibility-based patient-specific stress distribution maps in patients sustaining type A aortic dissection (TAAD) using predissection noninvasive imaging. METHODS: Review of charts from patients undergoing surgical repair of TAAD (n = 351) led to the selection of a subset population (n = 7) with 2 or more predissection computed tomography angiography scans and echocardiograms at least 1 year before dissection. Ascending aortic wall biomechanical properties (aortic strain, distensibility, and stiffness) were compared with age- and size-matched nondissected nonaneurysmal controls. Patient-specific aortic strain served as an input in aortic geometry-based simulated 3-dimensional reconstructions to generate longitudinal and circumferential wall stress maps. Inspection of perioperative dissection scans and intraoperative visual examination confirmed primary tear locations. RESULTS: Predissection echocardiography revealed ascending aortas of patients sustaining TAAD to exhibit decreased aortic wall strain (14.50 ± 1.13% vs 8.49 ± 1.08%; P < .01), decreased distensibility (4.26 ± 0.44 vs 2.39 ± 0.33 10-6 cm2·dyne-1; P < .01), increased stiffness (3.84 ± 0.24 vs 7.48 ± 1.05; P < .001), and increased longitudinal wall stress (246 ± 22 vs 172 ± 37 kPa; P < .01). There was no significant difference in circumferential wall stress. Predissection computed tomography angiography models revealed overlap between regions of increased longitudinal wall stress and primary tear sites. CONCLUSIONS: Using predissection imaging, we identified increased stiffness and longitudinal wall stress in ascending aortas of patients with dissection. Patient-specific imaging-derived biomechanical property maps like these may be instrumental toward designing better prediction models of aortic dissection potential.

Aortic clamping strategy and postoperative stroke.

OBJECTIVE: The effect of aortic clamping strategy on short-term stroke during proximal graft construction for coronary artery bypass grafting (CABG) remains undefined. The aim of this study was to test the hypothesis that partial occluding clamp (POC) technique does not increase incidence of postoperative stroke compared with single clamp (SC) technique for performing proximal coronary anastomoses. METHODS: We identified 52,611 patients who underwent on-pump CABG in the Society of Thoracic Surgeons Adult Cardiac Surgery Database from July 1, 2014 to March 31, 2015. Propensity scores for POC were calculated on the basis of validated Society of Thoracic Surgeons predicted risk of postoperative stroke scores and used to adjust for intergroup differences to derive 17,819 matched pairs for analysis. RESULTS: Despite a similar number of total bypass grafts between matched SC versus POC groups, myocardial ischemic times were shorter (74.1 ± 29.2 minutes vs 57.0 ± 23.3 minutes; P < .0001) as were cardiopulmonary bypass times (95.0 ± 35.0 minutes vs 89.7 ± 34.4 minutes; P < .0001) for the POC group. Postoperative stroke rates were similar between SC versus POC (0.9% vs 1.1%; risk ratio, 1.1; 95% confidence interval, 0.9-1.4; P = .3) as were mortality rates (1.3% vs 1.3%; risk ratio, 1.0; 95% confidence interval, 0.8-1.2; P = .9). CONCLUSIONS: Aortic clamping strategy for constructing proximal anastomoses in CABG procedures does not affect short-term incidence of postoperative stroke or mortality. The use of POC incurred shorter myocardial ischemic and perfusion times compared with the SC technique with similar total number of bypass grafts.

Carotid Artery Disease as a Predictor of In-Hospital Postoperative Stroke After Coronary Artery Bypass Grafting From 1999 to 2011.

BACKGROUND: In this study, the risk factors for stroke after coronary artery bypass grafting (CABG) were examined. In particular, the role of asymptomatic carotid artery stenosis (both unilateral and bilateral) as a predictor of in-hospital postoperative stroke was investigated. Finally, the trends surrounding in-hospital postoperative stroke from 1999 to 2011 also were examined. The purpose of the study was to appropriately identify patients at high risk for stroke after CABG and spark discussion about the perioperative management of such patients. MATERIALS AND METHODS: Data from the Nationwide Inpatient Sample from 1999 to 2011 were analyzed retrospectively. The study cohort was identified using the International Classification of Diseases, Ninth Revision, Clinical Modification and Projection Clinical Classification Software codes. Exploratory statistics, univariate analyses, and multivariable regression were used for this study. RESULTS: The analysis demonstrated that both asymptomatic unilateral and bilateral carotid stenoses were independent risk factors for in-hospital postoperative stroke. In addition, increasing age, female sex, increasing van Walraven score, paralysis, neurologic disorders, history of infective endocarditis, asymptomatic basilar stenosis, and cerebral occlusion all were demonstrated to be statistically significant predictors of stroke. Patients with carotid stenosis and a van Walraven score >14 were found to be particularly vulnerable to in-hospital postoperative stroke. Lastly, predictors of carotid stenosis were examined, and increasing age, female sex, and increasing van Walraven score all were found to be significant predictors of asymptomatic carotid stenosis. CONCLUSIONS: This study examined risk factors for stroke after CABG in a large, longitudinal, and population-based database. The study found that both unilateral and bilateral asymptomatic carotid stenoses are indeed risk factors for in-hospital postoperative stroke. In addition, a number of other predictors were identified. These results can be used to identify patients at high risk for perioperative stroke and hopefully decrease the rate of a devastating complication of CABG.

Delirium Following Transcatheter Aortic Valve Replacement: National Inpatient Sample Analysis.

OBJECTIVE: To investigate the risk factors for postoperative delirium and the impact of delirium on mortality and morbidity following transcatheter aortic valve implantation (TAVI). DESIGN: Patients who underwent TAVI were identified using the International Classification of Diseases, 9th revision clinical modification codes from the National Inpatient Sample database. Statistical analysis of preoperative and perioperative risk factors was done to identify the independent risk factors for delirium after TAVI. SETTING: Multi-institutional. PARTICIPANTS: Patients who underwent TAVI from 2012 to 2013. INTERVENTIONS: TAVI. MEASUREMENTS AND MAIN RESULTS: Over the period of 2 years (2012-2013), 7,566 patients underwent TAVI. The incidence of delirium post-TAVI was 4.57% (345). Age >85 (odds ratio [OR] 1.03; 95% confidence interval [CI] 1.01-1.05; p = 0.003), electrolyte abnormalities (OR 1.83; 95% CI 1.17-2.87; p = 0.008), prior neurologic illness (OR 1.67; 95% CI 1.10-3.15; p = 0.01), and weight loss in the hospital (OR 1.77; 95% CI 1.05-2.99; p = 0.03) were independent risk factors for postoperative delirium (POD). Unilateral or bilateral carotid stenosis did not predispose to the development of delirium. POD was an independent risk factor for procedural morbidity (OR 3.29; 95% CI 2.05-5.28; p < 0.001). POD did not increase the risk of in-house mortality after TAVI. CONCLUSION: Age of >85, electrolyte disturbance, pre-existing neurologic disease and weight loss were found to be independent risk factors for delirium. POD was associated significantly with morbidity. Owing to a significant increase in the morbidity, a thorough screening protocol and effective strategies to predict, prevent, and treat postoperative delirium would reduce the cost associated with TAVI.

Elevated oxidative stress in the aortic media of patients with bicuspid aortic valve.

OBJECTIVE: Congenital bicuspid aortic valve (BAV) is distinctly associated with the development of ascending aortopathy in adulthood, portending risk of both ascending aortic aneurysm and dissection. Our previous work implicated deficiency in oxidative stress response as a mediator of the BAV-associated aortopathy. We hypothesize that reactive oxygen species generation invokes elevated local oxidative tissue damage in ascending aorta of patients with BAV. METHODS: Ascending aortic specimens were obtained from patients undergoing elective aortic replacement and/or aortic valve replacement and during heart transplant operations. Levels of superoxide anion were measured via high-pressure liquid chromatography-based detection of 2-hydroxyethidium in aortic specimens. Lipid peroxidation and enzymatic activity of superoxide dismutase and peroxidase were quantified in aortic specimens. RESULTS: Superoxide anion production was elevated in aortic specimens from patients with nonaneurysmal BAV (n = 59) compared with specimens from patients with the morphologically normal tricuspid aortic valve (TAV, n = 38). Total superoxide dismutase activity was similar among aortic specimens from patients with TAV versus BAV (n = 27 and 26, respectively), whereas peroxidase activity was increased in aortic specimens from patients with BAV compared with specimens from patients with TAV (n = 14 for both groups). Lipid peroxidation was elevated in aortic specimens from BAV patients compared with TAV patients (n = 14 and 11, respectively). CONCLUSIONS: Superoxide anion accumulation and increased lipid peroxidation demonstrate that, despite increased peroxidase activity, the ascending aortopathy of patients with BAV involves oxidative stress. In addition, the absence of increased superoxide dismutase activity in BAV specimens indicates a deficiency in antioxidant defense. This suggests that the characteristic smooth muscle cell loss observed in BAV aortopathy may be a consequence of superoxide-mediated cell damage.

Perioperative Strokes and Early Outcomes in Mitral Valve Surgery: A Nationwide Analysis.

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.

Perivascular extracellular matrix hydrogels mimic native matrix microarchitecture and promote angiogenesis via basic fibroblast growth factor.

Extracellular matrix (ECM)-derived bioscaffolds have been shown to elicit tissue repair through retention of bioactive signals. Given that the adventitia of large blood vessels is a richly vascularized microenvironment, we hypothesized that perivascular ECM contains bioactive signals that influence cells of blood vessel lineages. ECM bioscaffolds were derived from decellularized human and porcine aortic adventitia (hAdv and pAdv, respectively) and then shown have minimal DNA content and retain elastin and collagen proteins. Hydrogel formulations of hAdv and pAdv ECM bioscaffolds exhibited gelation kinetics similar to ECM hydrogels derived from porcine small intestinal submucosa (pSIS). hAdv and pAdv ECM hydrogels displayed thinner, less undulated, and fibrous microarchitecture reminiscent of native adventitia, with slight differences in ultrastructure visible in comparison to pSIS ECM hydrogels. Pepsin-digested pAdv and pSIS ECM bioscaffolds increased proliferation of human adventitia-derived endothelial cells and this effect was mediated in part by basic fibroblast growth factor (FGF2). Human endothelial cells cultured on Matrigel substrates formed more numerous and longer tube-like structures when supplemented with pAdv ECM bioscaffolds, and FGF2 mediated this matrix signaling. ECM bioscaffolds derived from pAdv promoted FGF2-dependent in vivo angiogenesis in the chick chorioallantoic membrane model. Using an angiogenesis-focused protein array, we detected 55 angiogenesis-related proteins, including FGF2 in hAdv, pAdv and pSIS ECMs. Interestingly, 19 of these factors were less abundant in ECMs bioscaffolds derived from aneurysmal specimens of human aorta when compared with non-aneurysmal (normal) specimens. This study reveals that Adv ECM hydrogels recapitulate matrix fiber microarchitecture of native adventitia, and retain angiogenesis-related actors and bioactive properties such as FGF2 signaling capable of influencing processes important for angiogenesis. This work supports the use of Adv ECM bioscaffolds for both discovery biology and potential translation towards microvascular regeneration in clinical applications.