Early clinical outcomes and molecular smooth muscle cell phenotyping using a prophylactic aortic arch replacement strategy in Loeys-Dietz syndrome.

OBJECTIVES: Patients with Loeys-Dietz syndrome demonstrate a heightened risk of distal thoracic aortic events after valve-sparing aortic root replacement. This study assesses the clinical risks and hemodynamic consequences of a prophylactic aortic arch replacement strategy in Loeys-Dietz syndrome and characterizes smooth muscle cell phenotype in Loeys-Dietz syndrome aneurysmal and normal-sized downstream aorta. METHODS: Patients with genetically confirmed Loeys-Dietz syndrome (n = 8) underwent prophylactic aortic arch replacement during valve-sparing aortic root replacement. Four-dimensional flow magnetic resonance imaging studies were performed in 4 patients with Loeys-Dietz syndrome (valve-sparing aortic root replacement + arch) and compared with patients with contemporary Marfan syndrome (valve-sparing aortic root replacement only, n = 5) and control patients (without aortopathy, n = 5). Aortic tissues from 4 patients with Loeys-Dietz syndrome and 2 organ donors were processed for anatomically segmented single-cell RNA sequencing and histologic assessment. RESULTS: Patients with Loeys-Dietz syndrome valve-sparing aortic root replacement + arch had no deaths, major morbidity, or aortic events in a median of 2 years follow-up. Four-dimensional magnetic resonance imaging demonstrated altered flow parameters in patients with postoperative aortopathy relative to controls, but no clear deleterious changes due to arch replacement. Integrated analysis of aortic single-cell RNA sequencing data (>49,000 cells) identified a continuum of abnormal smooth muscle cell phenotypic modulation in Loeys-Dietz syndrome defined by reduced contractility and enriched extracellular matrix synthesis, adhesion receptors, and transforming growth factor-beta signaling. These modulated smooth muscle cells populated the Loeys-Dietz syndrome tunica media with gradually reduced density from the overtly aneurysmal root to the nondilated arch. CONCLUSIONS: Patients with Loeys-Dietz syndrome demonstrated excellent surgical outcomes without overt downstream flow or shear stress disturbances after concomitant valve-sparing aortic root replacement + arch operations. Abnormal smooth muscle cell-mediated aortic remodeling occurs within the normal diameter, clinically at-risk Loeys-Dietz syndrome arch segment. These initial clinical and pathophysiologic findings support concomitant arch replacement in Loeys-Dietz syndrome.

Lineage-Specific Induced Pluripotent Stem Cell-Derived Smooth Muscle Cell Modeling Predicts Integrin Alpha-V Antagonism Reduces Aortic Root Aneurysm Formation in Marfan Syndrome Mice.

BACKGROUND: The role of increased smooth muscle cell (SMC) integrin αv signaling in Marfan syndrome (MFS) aortic aneurysm remains unclear. Herein, we examine the mechanism and potential efficacy of integrin αv blockade as a therapeutic strategy to reduce aneurysm progression in MFS. METHODS: Induced pluripotent stem cells (iPSCs) were differentiated into aortic SMCs of the second heart field (SHF) and neural crest (NC) lineages, enabling in vitro modeling of MFS thoracic aortic aneurysms. The pathological role of integrin αv during aneurysm formation was confirmed by blockade of integrin αv with GLPG0187 in Fbn1C1039G/+ MFS mice. RESULTS: iPSC-derived MFS SHF SMCs overexpress integrin αv relative to MFS NC and healthy control SHF cells. Furthermore, integrin αv downstream targets (FAK [focal adhesion kinase]/AktThr308/mTORC1 [mechanistic target of rapamycin complex 1]) were activated, especially in MFS SHF. Treatment of MFS SHF SMCs with GLPG0187 reduced p-FAK/p-AktThr308/mTORC1 activity back to control SHF levels. Functionally, MFS SHF SMCs had increased proliferation and migration compared to MFS NC SMCs and control SMCs, which normalized with GLPG0187 treatment. In the Fbn1C1039G/+ MFS mouse model, integrin αv, p-AktThr308, and downstream targets of mTORC1 proteins were elevated in the aortic root/ascending segment compared to littermate wild-type control. Mice treated with GLPG0187 (age 6-14 weeks) had reduced aneurysm growth, elastin fragmentation, and reduction of the FAK/AktThr308/mTORC1 pathway. GLPG0187 treatment reduced the amount and severity of SMC modulation assessed by single-cell RNA sequencing. CONCLUSIONS: The integrin αv-FAK-AktThr308 signaling pathway is activated in iPSC SMCs from MFS patients, specifically from the SHF lineage. Mechanistically, this signaling pathway promotes SMC proliferation and migration in vitro. As biological proof of concept, GLPG0187 treatment slowed aneurysm growth and p-AktThr308 signaling in Fbn1C1039G/+ mice. Integrin αv blockade via GLPG0187 may be a promising therapeutic approach to inhibit MFS aneurysmal growth.

Analysis of the revised heart allocation policy and the influence of increased mechanical circulatory support on survival.

OBJECTIVES: In 2018, the new United Network for Organ Sharing heart allocation policy took effect. This study evaluated waitlist mortality, mechanical circulatory support utilization, and its influence on posttransplant survival. METHODS: Two 12-month cohorts matched for time of year before and after the policy change were defined by inclusion criteria of first-time transplant recipients aged 18 years or older who were listed and underwent transplant during the same era. Student t test and Wilcoxon rank-sum test were used for mean and median differences, respectively. Categorical variables were compared using χ2 or Fisher exact test. Kaplan-Meier curves were used to characterize survival, including time-to-event analysis with the log-rank test. Fine-Gray modeling was used to characterize waitlist mortality. Cox proportional-hazard models were used for multivariate analysis. RESULTS: Waitlist mortality in the new era is significantly improved based on a competing-risks model (Gray test P = .0064). Unadjusted 180-day posttransplant mortality increased from 5.8% during the old era to 8.0% during the new (P = .0134). However, time-to-event analysis showed similar 180-day survival in both eras. After risk adjustment, the hazard ratio for posttransplant 180-day mortality during the new era was 1.18 (95% CI, 0.85-1.64; P = .333). The posttransplant 180-day mortality of the extracorporeal membrane oxygenation bridge-to-transplant subgroup improved from 28.6% in the old era to 8.4% in the new era (P = .0103; log-rank P = .0021). Patients with an intra-aortic balloon pump at the time of transplant had similar 180-day posttransplant mortality between eras (5.4% vs 7.0%; P = .4831). CONCLUSIONS: The United Network for Organ Sharing policy change is associated with reduced waitlist mortality and similar risk adjusted posttransplant 180-day mortality. The new era is also associated with improved 180-day survival in patients undergoing bridge to transplant with extracorporeal membrane oxygenation.

A flexible electronic strain sensor for the real-time monitoring of tumor regression.

Assessing the efficacy of cancer therapeutics in mouse models is a critical step in treatment development. However, low-resolution measurement tools and small sample sizes make determining drug efficacy in vivo a difficult and time-intensive task. Here, we present a commercially scalable wearable electronic strain sensor that automates the in vivo testing of cancer therapeutics by continuously monitoring the micrometer-scale progression or regression of subcutaneously implanted tumors at the minute time scale. In two in vivo cancer mouse models, our sensor discerned differences in tumor volume dynamics between drug- and vehicle-treated tumors within 5 hours following therapy initiation. These short-term regression measurements were validated through histology, and caliper and bioluminescence measurements taken over weeklong treatment periods demonstrated the correlation with longer-term treatment response. We anticipate that real-time tumor regression datasets could help expedite and automate the process of screening cancer therapies in vivo.

Post-Transplant Extracorporeal Membrane Oxygenation for Severe Primary Graft Dysfunction to Support the Use of Marginal Donor Hearts.

Severe primary graft dysfunction (PGD) is the leading cause of early postoperative mortality following orthotopic heart transplantation (OHT). Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been used as salvage therapy. This study aimed to evaluate the outcomes in adult OHT recipients who underwent VA-ECMO for severe PGD. We retrospectively reviewed 899 adult (≥18 years) patients who underwent primary OHT at our institution between 1997 and 2017. Recipients treated with VA-ECMO (19, 2.1%) exhibited a higher incidence of previous cardiac surgery (p = .0220), chronic obstructive pulmonary disease (p = .0352), and treatment with a calcium channel blocker (p = .0018) and amiodarone (p = .0148). Cardiopulmonary bypass (p = .0410) and aortic cross-clamp times (p = .0477) were longer in the VA-ECMO cohort and they were more likely to have received postoperative transfusion (p = .0013); intra-aortic balloon pump (IABP, p < .0001), and reoperation for bleeding or tamponade (p < .0001). The 30-day, 1-year, and overall survival after transplantation of non-ECMO patients were 95.9, 88.8, and 67.4%, respectively, compared to 73.7, 57.9, and 47.4%, respectively in the ECMO cohort. Fourteen (73.7%) of the ECMO patients were weaned after a median of 7 days following OHT (range: 1-12 days). Following OHT, VA-ECMO may be a useful salvage therapy for severe PGD and can potentially support the usage of marginal donor hearts.

Twelfth Interagency Registry for Mechanically Assisted Circulatory Support Report: Readmissions After Left Ventricular Assist Device.

The twelfth annual report from The Society of Thoracic Surgeons (STS) Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) highlights outcomes for 26 688 continuous-flow left ventricular assist device (LVAD) patients over the past decade (2011-2020). In 2020, we observed the largest drop in yearly LVAD implant volumes since the registry's inception, which reflects the effects of the COVID-19 pandemic on cardiac surgical volumes in the United States. The 2018 heart transplant allocation policy change in the United States continues to affect LVAD implantation volumes and device strategy, with 78.1% of patients now receiving LVAD implants as destination therapy. Despite an older and sicker patient cohort, survival in the recent era (2016-2020) at 1 and 2 years continues to improve at 82.8% and 74.1%. Patient adverse event profile has also improved in the recent era, with significant reductions in stroke, gastrointestinal bleeding, infection, and device malfunction/pump thrombosis. Finally, we review the burden of readmissions after LVAD implant and highlight an opportunity to improve patient outcomes by reducing this frequent and vexing problem.

Donor and Recipient Size Matching in Heart Transplantation With Predicted Heart and Lean Body Mass.

Donor and recipient size matching during heart transplant can be assessed using weight or predicted heart mass (PHM) ratios. We developed sex-specific allomteric equations for PHM and predicted lean body mass (PLBM) using the United Kingdom Biobank (UKB) and evaluated their predictive value in the United Network of Organ Sharing database. Donor and recipient size matching was based on weight, PHM and PLBM ratios. PHM was calculated using the Multiethnic Study of Atherosclerosis and UKB equations. PLBM was calculated using the UKB and National Health and Nutrition Examination Survey equations. Relative prognostic utility was compared using multivariable Cox analysis, adjusted for predictors of 1-year survival in the Scientific Registry of Transplant Recipients model. Of 53,648 adult patients in the United Network of Organ Sharing database between 1996 and 2016, 6528 (12.2%) died within the first year. In multivariable analysis, undersized matches by any metric were associated with increased 1-year mortality (all P < 0.01). Oversized matches were at increased risk using PHM or PLBM (all P < 0.01), but not weight ratio. There were significant differences in classification of size matching by weight or PHM in sex-mismatched donor-recipient pairs. A significant interaction was observed between pulmonary hypertension and donor undersizing (hazard ratio 1.15, P = 0.026) suggesting increased risk of undersizing in pulmonary hypertension. Donor and recipient size matching with simplified PHM and PLBM offered an advantage over total body weight and may be more important for sex-mismatched donor-recipient pairs. Donor undersizing is associated with worse outcomes in patients with pulmonary hypertension.

Computational Fluid Dynamics Simulations to Predict False Lumen Enlargement After Surgical Repair of Type-A Aortic Dissection.

We aim to use computational fluid dynamics to investigate the hemodynamic conditions that may predispose to false lumen enlargement in this patient population. Nine patients who received surgical repairs of their type-A aortic dissections between 2017-2018 were retrospectively identified. Multiple contrast-enhanced post-operative CT scans were used to construct 3D models of aortic geometries. Computational fluid dynamics simulations of the models were run on a high-performance computing cluster using SimVascular - an open-source simulation package. Physiological pulsatile flow conditions (4.9 L/min) were used at the aortic true lumen inlet, and physiological vascular resistances were applied at the distal vascular ends. Exploratory analyses showed no correlation between rate of false lumen growth and blood pressure, immediate post-op aortic diameter, or the number of fenestrations (p = 0.2). 1-year post-operative CT scans showed a median false lumen growth rate of 4.31 (3.66, 14.67) mm/year Median (Interquartile range) peak systolic, mid-diastolic, and late diastolic velocity magnitudes were 0.90 (1.40); 0.10 (0.16); and 0.06 (0.06) cm/s respectively. Spearman's ranked correlations between fenestration velocity and 1-year false lumen growth rates were found to be statistically significant: Velocity magnitude at peak systolic (p = 0.025; rho = 0.75), mid diastolic (p = 0.025; rho = 0.75) and late diastolic phases of the cardiac cycle (p = 0.006; rho = 0.85). We have shown that false lumen growth is strongly correlated to fenestration flow velocity, which has potential implications for post-operative surveillance and risk stratification.

Long-term survival in patients with post-LVAD right ventricular failure: multi-state modelling with competing outcomes of heart transplant.

BACKGROUND: Multicenter data on long term survival following LVAD implantation that make use of contemporary definitions of RV failure are limited. Furthermore, traditional survival analyses censor patients who receive a bridge to heart transplant. Here we compare the outcomes of LVAD patients who develop post-operative RV failure accounting for the transitional probability of receiving an interim heart transplantation. METHODS: We use a retrospective cohort of LVAD patients sourced from multiple high-volume centers based in the United States. Five- and ten-year survival accounting for transition probabilities of receiving a heart transplant were calculated using a multi-state Aalen Johansen survival model. RESULTS: Of the 897 patients included in the study, 238 (26.5%) developed post-operative RV failure at index hospitalization. At 10 years the probability of death with post-op RV failure was 79.28% vs 61.70% in patients without (HR 2.10; 95% CI 1.72 - 2.57; p = < .001). Though not significant, patients with RV failure were less likely to be bridged to a heart transplant (HR 0.87, p = .4). Once transplanted the risk of death between both patient groups remained equivalent; the probability of death after a heart transplant was 3.97% in those with post-operative RV failure shortly after index LVAD implant, as compared to 14.71% in those without. CONCLUSIONS AND RELEVANCE: Long-term durable mechanical circulatory support is associated with significantly higher mortality in patients who develop post-operative RV failure. Improving outcomes may necessitate expeditious bridge to heart transplant wherever appropriate, along with critical reassessment of organ allocation policies.

The Use of Factor Eight Inhibitor Bypass Activity (FEIBA) for the Treatment of Perioperative Hemorrhage in Left Ventricular Assist Device Implantation.

OBJECTIVE: To test the hypothesis that factor eight inhibitor bypassing activity (FEIBA) can be used to control bleeding following left ventricular assist device (LVAD) implantation without increasing the 14-day composite thrombotic outcome of pump thrombus, ischemic cerebrovascular accidents, pulmonary embolism, and deep venous thrombosis. DESIGN: Retrospective cohort study. SETTING: Academic hospital. PARTICIPANTS: Three hundred nineteen consecutive patients who underwent LVAD implantation (December 1, 2009 to December 30, 2018). INTERVENTION: FEIBA administered to control perioperative hemorrhage. MEASUREMENTS AND MAIN RESULTS: The 82 patients (25.7%) in the FEIBA cohort had more risk factors for perioperative hemorrhage, such as lower preoperative platelet count (169 ± 66 v 194 ± 68 × 103/mL, p = 0.004), prior cardiac surgery (36.6% v 21.9%, p = 0.008), and longer cardiopulmonary bypass (CPB) time (100.3 v 75.2 minutes, p = 0.001) than the 237 controls. After 16.6 units (95% CI: 14.3-18.9) of blood products were given, 992 units (95% CI: 821-1163) of FEIBA were required to control bleeding in the FEIBA cohort. Compared to the controls, there were no differences in the 14-day composite thrombotic outcome (11.0% v 7.6%, p = 0.343) or mortality rate (3.7% v 1.3%, p = 0.179). Multivariate logistical regression identified preoperative international normalized ratio (odds ratio [OR]: 1.30, 95% CI: 1.04-1.62) and CPB time (OR: 1.11, 95% CI: 1.02-1.20) as risk factors for 14-day thrombotic events, but FEIBA usage was not associated with an increased risk. CONCLUSIONS: In this retrospective cohort study, the use of FEIBA (∼1,000 units, ∼13 units/kg) to control perioperative hemorrhage following LVAD implantation was not associated with increases in mortality or composite thrombotic outcome.

Use of patient-specific computational models for optimization of aortic insufficiency after implantation of left ventricular assist device.

OBJECTIVE: Aortic incompetence (AI) is observed to be accelerated in the continuous-flow left ventricular assist device (LVAD) population and is related to increased mortality. Using computational fluid dynamics (CFD), we investigated the hemodynamic conditions related to the orientation of the LVAD outflow in these patients. METHOD: We identified 10 patients with new aortic regurgitation, and 20 who did not, after LVAD implantation between 2009 and 2018. Three-dimensional models of patients' aortas were created from their computed tomography scans. The geometry of the LVAD outflow graft in relation to the aorta was quantified using azimuth angles (AA), polar angles (PAs), and distance from aortic root. The models were used to run CFD simulations, which calculated the pressures and wall shear stress (rWSS) exerted on the aortic root. RESULTS: The AA and PA were found to be similar. However, for combinations of high values of AA and low values of PA, there were no patients with AI. The distance from aortic root to the outflow graft was also smaller in patients who developed AI (3.39 ± 0.7 vs 4.07 ± 0.77 cm, P = .04). There was no significant difference in aortic root pressures in the 2 groups. The rWSS was greater in AI patients (4.60 ± 5.70 vs 2.37 ± 1.20 dyne/cm2, P < .001). Qualitatively, we observed a trend of greater perturbations, regions of high rWSS, and flow eddies in the AI group. CONCLUSIONS: Using CFD simulations, we demonstrated that patients who developed de novo AI have greater rWSS at the aortic root, and their outflow grafts were placed closer to the aortic roots than those patients without de novo AI.

Impact of Surgical Approach in Double Lung Transplantation: Median Sternotomy vs Clamshell Thoracotomy.

BACKGROUND: Double lung transplantation (DLT) remains the gold standard for end-stage lung disease. Although DLT was historically performed via clamshell thoracotomy, recently the median sternotomy has emerged as a viable alternative. As the ideal surgical approach remains unclear, the aim of our study was to compare the short- and long-term outcomes of these 2 surgical approaches in DLT. METHODS: We retrospectively reviewed 192 consecutive adult patients who underwent primary DLT at our institution between 2012 and 2017 (sternotomy, n = 147; clamshell, n = 45). The impact of each surgical approach on post-transplant morbidity was investigated, and the overall survival probability analyses were performed. RESULTS: There were no significant differences in recipients' baseline and donors' characteristics and bilateral allograft ischemic time. Freedom from primary graft dysfunction, acute rejection episodes, postoperative prolonged ventilator support, tracheostomy, postoperative stroke, and airway dehiscence were comparable between these 2 groups. The duration of cardiopulmonary bypass and operative time were significantly longer in the clamshell thoracotomy group. Postoperative extracorporeal membrane oxygenation usage tended to be more frequent in the clamshell thoracotomy group than the median sternotomy group, despite no statistical significance. Length of hospital and intensive care unit stay were not influenced by the type of incision. There was no significant difference in overall survival between these 2 procedure groups (P = .61, log-rank test). CONCLUSIONS: The median sternotomy approach in DLT decreases operative time and more importantly leads to a shorter duration of cardiopulmonary bypass. The type of surgical approach did not show any statistically significant impact on adult DLT recipients' morbidity and survival.

Predicting Transfusions During Left Ventricular Assist Device Implant.

Perioperative bleeding and transfusion cause morbidity and mortality in patients receiving left ventricular assist devices (LVADs). We assessed factors associated with transfusions within 30 days of durable LVAD implantation and the clinical outcomes associated with transfusions. A retrospective cohort study of patients undergoing initial durable LVAD implantation between 2014 and 2016 was performed. Rates of packed red blood cell (PRBC) or other blood product transfusions (platelets or fresh frozen plasma) were assessed. Ordinal multivariable regression analysis was performed to determine factors independently associated with transfusion. Analysis included 156 patients, mean age 54.6 years and 74.4% male, who received a mean of 11.7 units of PRBC and 10.0 units of other products within 30 days. Preimplant mechanical ventilation, dialysis, higher INR, previous sternotomy, higher model for end-stage liver disease score, and lower hemoglobin were associated with increased PRBC transfusion rates. Higher preoperative central venous pressure, mechanical ventilation, concomitant surgical procedures, previous sternotomy, and lower hemoglobin were associated with increased PRBC transfusion rates within 48 hours of implant (adjusted odds ratio [OR] 1.46, P = 0.013 per 5 mm Hg). There were no significant associations with ferritin (adjusted OR 1.00, P = 0.236) or transferrin saturation (adjusted OR 1.17, P = 0.068). Transfusions were associated with an increase in ventilation duration, intensive care unit length of stay, reoperation for bleeding, and all-cause mortality. In patients undergoing LVAD implantation, perioperative blood product exposure is common and associated with increased morbidity and mortality. Elevated central venous pressure and anemia are potentially modifiable factors associated with increased early PRBC transfusion rates.

Risk of reoperative valve surgery for endocarditis associated with drug use.

BACKGROUND: We aimed to quantify incidence and operative risks associated with reoperative valve surgeries (RVS) in patients with drug-associated infective endocarditis in a multi-center setting. METHODS: We formed a registry of patients with drug-associated infective endocarditis who underwent valve surgeries at 8 US centers between 2011 and 2017. Outcomes of first-time valve surgery (FVS) and RVS were compared. Multivariable logistic regression models related RVS to 30-day mortality. Poisson regression models were fitted to evaluate temporal trends in overall case volume and proportions of patients undergoing RVS. RESULTS: The cohort consisted of 925 patients with drug-associated infective endocarditis who underwent a valve surgery, of which 652 were FVS and 273 were RVS. Patients undergoing FVS had fewer comorbidities than those undergoing RVS. Overall case volume increased from 108 in 2012 to 229 cases in 2017 (P < .001). The proportion of redo valve cases increased from 19% in 2012 to 28% in 2017 (P < .001). The 30-day mortality in RVS was higher compared with FVS (8.1% vs 4.8%; P = .049). An increase in unadjusted mortality rates were observed as the number of prior cardiac surgeries increased, from 4.8% in FVS to 11.8% in ≥3 RVS. Multivariable model demonstrated that RVS was associated with an increased risk of 30-day mortality (odds ratio, 2.22; 95% confidence interval, 1.22-4.06; P = .010). CONCLUSIONS: An increasing proportion of valve surgery for drug-associated infective endocarditis is for RVS. Despite being young and harboring few comorbidities, the RVS cohort is still susceptible to increased risk of 30-day mortality compared with those undergoing FVS.

Evaluation of Risk Factors for Heart-Lung Transplant Recipient Outcome: An Analysis of the United Network for Organ Sharing Database.

BACKGROUND: Heart-lung transplantation (HLTx) is an effective treatment for patients with advanced cardiopulmonary failure. However, no large multicenter study has focused on the relationship between donor and recipient risk factors and post-HLTx outcomes. Thus, we investigated this issue using data from the United Network for Organ Sharing database. METHODS: All adult patients (age ≥18 years) registered in the United Network for Organ Sharing database who underwent HLTx between 1987 and 2017 were included (n=997). We stratified the cohort by patients who were alive without retransplant at 1 year (n=664) and patients who died or underwent retransplant within 1 year of HLTx (n=333). The primary outcome was the influence of donor and recipient characteristics on 1-year post-HLTx recipient death or retransplant. Kaplan-Meier curves were created to assess overall freedom from death or retransplant. To obtain a better effect estimation on hazard and survival time, the parametric Accelerated Failure Time model was chosen to perform time-to-event modeling analyses. RESULTS: Overall graft survival at 1-year post-HLTx was 66.6%. Of donors, 53% were male, and the mean age was 28.2 years. Univariable analysis showed advanced donor age, recipient male sex, recipient creatinine, recipient history of prior cardiac or lung surgery, recipient extracorporeal membrane oxygenation support, transplant year, and transplant center volume were associated with 1-year post-HLTx death or retransplant. On multivariable analysis, advanced donor age (hazard ratio [HR], 1.017; P=0.0007), recipient male sex (HR, 1.701; P=0.0002), recipient extracorporeal membrane oxygenation support (HR, 4.854; P<0.0001), transplant year (HR, 0.962; P<0.0001), and transplantation at low-volume (HR, 1.694) and medium-volume centers (HR, 1.455) in comparison with high-volume centers (P=0.0007) remained as significant predictors of death or retransplant. These predictors were incorporated into an equation capable of estimating the preliminary probability of graft survival at 1-year post-HLTx on the basis of preoperative factors alone. CONCLUSIONS: HLTx outcomes may be improved by considering the strong influence of donor age, recipient sex, recipient hemodynamic status, and transplant center volume. Marginal donors and recipients without significant factors contributing to poor post-HLTx outcomes may still be considered for transplantation, potentially with less impact on the risk of early postoperative death or retransplant.

A modified implantation technique for temporary right ventricular assist device: Enabling ambulation and less invasive decannulation.

This report describes our unique temporary right ventricular assist device (RVAD) implantation technique, which enables early mobilization even during biventricular support and subsequent less invasive RVAD removal without needing resternotomy upon recovery.

Right ventricular load adaptability metrics in patients undergoing left ventricular assist device implantation.

OBJECTIVE: Several right load adaptability metrics have been proposed as predictors of right heart failure (RHF) following left ventricular assist device implantation. This study sought to validate and compare the prognostic value of these indices. METHODS: This retrospective study included 194 patients undergoing continuous-flow left ventricular assist device implantation. The primary end point was unplanned right atrial assist device (RVAD) need within 30 days after left ventricular assist device implantation; the secondary end points included clinical RHF syndrome without RVAD need and the composite of RHF or RVAD need. Load adaptability indices or interventricular ratios were divided into surrogates of ventriculoarterial coupling (RV area change:end-systolic area), indices reflecting adaptation proportionality (Dandel's index = tricuspid regurgitation velocity-time integral normalized for average RV radius in diastole or systole), and simple ratios (eg, pulse pressure:right atrial pressure or right arterial pressure:pulmonary arterial wedge pressure). RESULTS: Mean age was 55 ± 13 years with 77% of men. RHF occurred in 75 patients with 30 patients requiring RVAD implantation. Among right heart metrics, right arterial pressure (normalized odd ratio, 1.62; 95% confidence interval, 1.15-2.38), right arterial pressure:pulmonary arterial wedge pressure (normalized odds ratio, 1.59; 95% confidence interval, 1.08-2.32) and pulse pressure:right arterial pressure < 2.0 (normalized odds ratio, 2.56; 95% confidence interval, 1.16-5.56) were associated with RVAD need (all P values < .02). These 3 metrics significantly added incremental prognostic value to the Interagency Registry for Mechanically Assisted Circulatory Support classification score in a similar range, whereas only RAP was incremental to the Michigan score. Correlates of RHF not requiring RVAD included RV end-systolic area index and the Dandel indices, which provided similar incremental value to the Interagency Registry for Mechanically Assisted Circulatory Support, Michigan, and European Registry for Patients with Mechanical Circulatory Support scores. CONCLUSIONS: Although associated with outcome, right load adaptability indices do not appear to provide strong incremental value when compared with simple metrics.

Successful Repair of Type A Aortic Dissection in an Octogenarian With Double Aortic Arch.

An 80-year-old woman was transferred to our institution with a subacute type A aortic dissection and a previously undiagnosed double aortic arch. The patient underwent successful repair with aortic valve resuspension, ascending aortic replacement, and repair of the proximal right-sided arch. This is the first reported case of a type A dissection associated with a double aortic arch in the United States.