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Background: Extracorporeal membrane oxygenation (ECMO) has gained traction as a bridge to heart transplantation (HT) but remains associated with increased waitlist mortality. This study explores whether this risk is modified by underlying heart failure (HF) etiology., Methods: Using the Organ Procurement and Transplantation Network registry, we conducted a retrospective review of first-time adult HT candidates from 2018 through 2022. Patients were categorized as "ECMO", if ECMO was utilized during the waitlisting period, or "No ECMO" otherwise. Patients were then stratified according to the following HF etiology: ischemic cardiomyopathy (CMP), dilated nonischemic CMP, restrictive CMP, hypertrophic CMP, and congenital heart disease (CHD). After baseline comparisons, waitlist mortality was characterized for ECMO and HF etiology using the Fine-Gray regression., Results: A total of 16 143 patients were identified of whom 7.0% (n = 1063) were bridged with ECMO. Compared to No ECMO patients, ECMO patients had shorter waitlist durations (46.3 vs. 185.0 days, p < 0.01) and were more likely to undergo transplantation (75.3% vs. 70.3%, p < 0.01). Outcomes analysis revealed that ECMO was associated with increased mortality risk (subdistribution hazard ratio [SHR]: 3.42, p < 0.01), a risk that persisted in all subgroups and was notably high in CHD (SHR: 4.83, p < 0.01) and hypertrophic CMP (SHR: 9.78, p < 0.01). HF etiology comparison within ECMO patients revealed increased mortality risk with CHD (SHR: 3.22, p < 0.01). Within No ECMO patients, hypertrophic CMP patients had lower mortality risk (SHR: 0.64, p = 0.03)., Conclusions: The increased waitlist mortality risk with ECMO persisted after stratification by HF etiology. These findings can help decision-making surrounding candidacy for cannulation and prognostic evaluation., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Detecting right heart failure post left ventricular assist device (LVAD) is challenging. Sensitive pressure-volume loop assessments of right ventricle (RV) contractility may improve our appreciation of post-LVAD RV dysfunction., Methods: Thirteen LVAD patients and 20 reference (non-LVAD) subjects underwent comparison of echocardiographic, right heart cath hemodynamic, and pressure-volume loop-derived assessments of RV contractility using end-systolic elastance (Ees), RV afterload by effective arterial elastance (Ea), and RV-pulmonary arterial coupling (ratio of Ees/Ea)., Results: LVAD patients had lower RV Ees (0.20 ± 0.08 vs 0.30 ± 0.15 mm Hg/ml, p = 0.01) and lower RV Ees/Ea (0.37 ± 0.14 vs 1.20 ± 0.54, p < 0.001) versus reference subjects. Low RV Ees correlated with reduced RV septal strain, an indicator of septal contractility, in both the entire cohort (r = 0.68, p = 0.004) as well as the LVAD cohort itself (r = 0.78, p = 0.02). LVAD recipients with low RV Ees/Ea (below the median value) demonstrated more clinical heart failure (71% vs 17%, p = 0.048), driven by an inability to augment RV Ees (0.22 ± 0.11 vs 0.19 ± 0.02 mm Hg/ml, p = 0.95) to accommodate higher RV Ea (0.82 ± 0.38 vs 0.39 ± 0.08 mm Hg/ml, p = 0.002). Pulmonary artery pulsatility index (PAPi) best identified low baseline RV Ees/Ea (≤0.35) in LVAD patients ((area under the curve) AUC = 0.80); during the ramp study, change in PAPi also correlated with change in RV Ees/Ea (r = 0.58, p = 0.04)., Conclusions: LVAD patients demonstrate occult intrinsic RV dysfunction. In the setting of excess RV afterload, LVAD patients lack the RV contractile reserve to maintain ventriculo-vascular coupling. Depression in RV contractility may be related to LVAD left ventricular unloading, which reduces septal contractility., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: We sought to quantify the impact of pre- and postoperative variables on health-related quality of life (HRQOL) after left ventricular assist device (LVAD) implantation., Methods: Primary durable LVAD implants between 2012 and 2019 in the Interagency Registry for Mechanically Assisted Circulatory Support were identified. Multivariable modeling using general linear models assessed the impact of baseline characteristics and postimplant adverse events (AEs) on HRQOL as assessed by the EQ-5D visual analog scale (VAS) and the Kansas City Cardiomyopathy Questionnaire-12 (KCCQ) at 6 months and 3 years., Results: Of 22,230 patients, 9,888 had VAS and 10,552 had KCCQ reported at 6 months, and 2,170 patients had VAS and 2,355 had KCCQ reported at 3 years postimplant. VAS improved from a mean of 38.2 ± 28.3 to 70.7 ± 22.9 at 6 months and from 40.1 ± 27.8 to 70.3 ± 23.1 at 3 years. KCCQ improved from 28.2 ± 23.9 to 64.3 ± 23.2 at 6 months and from 29.8 ± 23.7 to 63.0 ± 23.7 at 3 years. Preimplant variables, including baseline VAS, had small effect sizes on HRQOL while postimplant AEs had large negative effect sizes. Recent stroke, respiratory failure, and renal dysfunction had the largest negative effect on HRQOL at 6 months, while recent renal dysfunction, respiratory failure, and infection had the largest negative effect at 3 years., Conclusions: AEs following LVAD implantation have large negative effects on HRQOL in early and late follow-up. Understanding the impact of AEs on HRQOL may assist shared decision-making regarding LVAD eligibility. Continued efforts to reduce post-LVAD AEs are warranted to improve HRQOL in addition to survival., (Copyright © 2023 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to describe the changes in plasma levels of angiogenic and inflammatory biomarkers, specifically Ang-2 and TNF-α, in patients receiving HeartMate II (HMII) left ventricular assist device (LVAD) and correlate them with nonsurgical bleeding. It has been shown that angiopoietin-2 (Ang-2) and tissue necrosis factor-α (TNF-α) may be linked to bleeding in LVAD patients. This study utilized biobanked samples prospectively collected from the PREVENT study, a prospective, multicenter, single-arm, nonrandomized study of patients implanted with HMII. Paired serum samples were obtained in 140 patients before implantation and at 90 days postimplantation. Baseline demographics were as follows: age 57 ± 13 years, 41% had ischemic etiology, 82% male, and 75% destination therapy indication. In the 17 patients with baseline elevation of both TNF-α and Ang-2, 10 (60%) experienced a significant bleeding event within 180 days postimplant compared with 37 of 98 (38%) patients with Ang-2 and TNF-α below the mean ( p = 0.02). The hazard ratio for a bleeding event was 2.3 (95% CI: 1.2-4.6) in patients with elevated levels of both TNF-α and Ang-2. In the PREVENT multicenter study, patients with elevations in serum Angiopoietin-2 and TNF-α at baseline before LVAD implantation demonstrated increased bleeding events after LVAD implantation., Competing Interests: Disclosure: G.S. and A.K. received consulting from Abbott. J.L. received consulting from Novartis, Abbott, Resmed, Edwards, VWave, Impulse Dynamics, and CVRx. G.E. received consulting from Abbott. P.S. received grant support from Medtronic, and Abbott and consulting from NuPulse CV. Jeanine Walenga: received grant support from Abbott. D.C., D.F., and K.S. are the employees of Abbott. Nir Uriel received consulting from Abbott. The other authors have no conflicts of interest to report., (Copyright © ASAIO 2023.)

Introduction: We investigated how the 2018 Organ Procurement and Transplantation Network heart allocation policy change was associated with changes in characteristics and outcomes of candidates receiving multiple temporary mechanical circulatory support (mtMCS) devices., Materials and Methods: We included adult heart transplant candidates listed October 2014-January 2018 and October 2018-January 2022 in the United Network of Organ Sharing dataset. Prepolicy and postpolicy mtMCS recipients were compared at listing, transplant, 90-days, and 1-year post-transplant. Time between first and second devices and time between first device and transplant were modeled via multivariable linear regression. Transplantation likelihood was modeled using competing risks analysis., Results: Postpolicy, a higher proportion of transplant candidates received mtMCS (4% versus 1%, P < 0.001), and received their second device an adjusted 49 d sooner versus prepolicy (P = 0.001). Time to transplant was also an adjusted 35 d shorter postpolicy, with an 80% increased transplantation likelihood versus prepolicy (95% confidence interval: 1.6-1.9, P < 0.001). Postpolicy patients experienced reduced waitlist mortality (8% versus 14%, P = 0.04) with marked improvements in 90-day (93% versus 85%, P < 0.001) and 1-year (88% versus 70%, P = 0.01) post-transplant survival., Conclusions: Postpolicy mtMCS recipients are more likely to progress to transplantation sooner on the waitlist and their shorter waitlist course together with earlier change to a secondary device was associated with improved post-transplant survival versus prepolicy., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Late right heart failure (LRHF) following left ventricular assist device (LVAD) implantation remains poorly characterized and challenging to predict. We performed a multicenter retrospective study of LRHF in 237 consecutive adult LVAD patients, in which LRHF was defined according to the 2020 Mechanical Circulatory Support Academic Research Consortium guidelines. Clinical and hemodynamic variables were assessed pre- and post-implant. Competing-risk regression and Kaplan-Meier survival analysis were used to assess outcomes. LRHF prediction was assessed using multivariable logistic and Cox proportional hazards regression. Among 237 LVAD patients, 45 (19%) developed LRHF at a median of 133 days post-LVAD. LRHF patients had more frequent heart failure hospitalizations ( p < 0.001) alongside other complications. LRHF patients did not experience reduced bridge-to-transplant rates but did suffer increased mortality (hazard ratio 1.95, 95% confidence interval [CI] 1.11-3.42; p = 0.02). Hemodynamically, LRHF patients demonstrated higher right atrial pressure, mean pulmonary arterial pressure, and pulmonary vascular resistance (PVR), but no difference in pulmonary arterial wedge pressure. History of early right heart failure, blood urea nitrogen (BUN) > 35 mg/dl at 1 month post-LVAD, and diuretic requirements at 1 month post-LVAD were each significant, independent predictors of LRHF in multivariable analysis. An LRHF prediction risk score incorporating these variables predicted LRHF with excellent discrimination (log-rank p < 0.0001). Overall, LRHF post-LVAD is more common than generally appreciated, with significant morbidity and mortality. Elevated PVR and precapillary pulmonary pressures may play a role. A risk score using early right heart failure, elevated BUN, and diuretic requirements 1 month post implant predicted the development of LRHF., Competing Interests: Disclosure: R.T. reports general disclosures to include consulting relationships with Medtronic, Abbott, Aria CV Inc., Acceleron, Itamar, Edwards LifeSciences, Eidos Therapeutics, Lexicon Pharmaceuticals, Gradient and United Therapeutics. He is on a steering committee for Medtronic, Acceleron, and Abbott as well as on a research advisory board for Abiomed. He also does hemodynamic core lab work for Actelion and Merck. The other authors have no conflicts of interest to report.., (Copyright © ASAIO 2022.)

The aim of this investigation was to characterize the hemostatic status of heart failure patients with implanted left ventricular assist devices (LVADs) to propose a mechanism associated with bleeding. Patients (n = 300) from 23 US hospitals were enrolled in the PREVENtion of HeartMate II Pump Thrombosis through Clinical Management (PREVENT) study. A biobank was established with serum and plasma samples prospectively collected from a cohort of 175 patients preimplant baseline (BL) and 3 months (3M) postimplant. Outcomes were collected for 6 months. Thrombin (prothrombin fragment 1.2 [F1.2], functional thrombin generation [TG]) and fibrinolytic activity (D-dimer, plasminogen activator inhibitor-1 [PAI-1]), but not contact activation (complement C5a), were elevated in heart failure patients at BL. F1.2, TG, and PAI-1 levels decreased 3M after LVAD implantation ( p < 0.01) but did not revert to normal in all patients; conversely, D-dimer increased BL to 3M ( p < 0.01). Compared with patients without events, thrombin activity (F1.2) was increased in patients with late bleeding (3-4 months postimplant) ( p = 0.06) and in those with late gastrointestinal (GI) bleeding ( p = 0.01). Patients with 3M F1.2 levels above the cohort mean had a higher incidence of bleeding ( p < 0.001) and GI bleeding ( p < 0.001) compared with those with below mean F1.2. Patients experiencing multiple bleeding events were more likely to have 3M F1.2 greater than the cohort mean. Despite anticoagulation with aspirin and warfarin, LVAD implanted patients exhibit hemostatic activation. Excess thrombin formation, particularly shown by increased F1.2, was demonstrated in association with bleeding in LVAD implanted patients., Competing Interests: Disclosure: A.K. and N.U.: Consultant – Abbott. J.L.: Consultant - Novartis, Abbott, Relypsa, and Resmed. P.S.: research grants - AHA/Enduring Hearts, Haemonetics, Medtronic, and Merck. D.C. and D.J.F.: Employee – Abbott. J.M.W.: research grant – Abbott. The remaining authors have no conflicts of interest to report., (Copyright © ASAIO 2022.)

Background: Coronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%)., Methods: We analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively., Results: In 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5])., Conclusions: Heart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization., (Published by Elsevier Inc.)

Ventricular assist devices (LVADs) are commonly used in end-stage heart failure for mechanical circulatory support as a bridge to heart transplantation. However, LVADs' long-term effects on posttransplant survival are unknown. We sought to compare long-term mortality after transplantation for patients with and without LVADs. Using the Organ Procurement and Transplantation Network database, we investigated LVADs' impact on long-term (3 month, 1 year, 2 years, 5 years, and 8 years) posttransplant mortality risk for all heart transplant recipients between 2010 and 2019. Time-to-event regression analysis quantified mortality risk by LVAD status in both unconditional and conditional survival analyses. Of 20,113 transplant recipients, 8,999 (45%) had a LVAD while on the waitlist. Among those who died after transplantation, patients with LVADs on average died sooner (1.8 years) than patients without LVADs (3.0 years; p < 0.01). On multivariable analysis, patients with LVADs had a 44% higher mortality risk within the first 3 months posttransplant (HR = 1.44, p = 0.03). There was no significant difference in mortality risk between patients who did and did not have pretransplant LVADs after 1, 2, and 5 years of posttransplant conditional survival. While LVAD patients have a survival disadvantage in the first year posttransplant, conditional survival analysis demonstrated no difference in mortality risk between patients with and without LVADs beyond 1 year of follow up. Of the patients who died posttransplant, patients with LVADs on average died sooner than patients without LVADs., Competing Interests: The authors have no conflicts of interest or sources of funding to disclose., (Copyright © ASAIO 2022.)

Aims: Despite the common occurrence of coronary artery disease (CAD) and heart failure (HF) with preserved ejection fraction (HFpEF), there is limited evidence to guide revascularization., Methods and Results: We investigated the long-term outcomes of coronary artery bypass grafting (CABG) in patients with HF and significant CAD across the spectrum of ejection fraction, using a large national cohort of patients from the Veteran Affairs (VA) Medical Centers in the US. Patients with HF were stratified into groups, HFpEF, HF with mid-range ejection fraction (HFmrEF), and HF with reduced ejection fraction (HFrEF) and compared to patients with no preoperative HF. We analysed 10 396 patients. Despite an increased hazard in the first year following revascularization, the long-term survival (median follow-up 6.6 years; interquartile range 3.7-10.1) of HFpEF post-CABG was similar to controls (hazard ratio 0.85, 95% confidence interval 0.68-1.06), but survival progressively declined with HFmrEF and HFrEF. Similar trends were seen with recurrent HF hospitalization with lower risk with baseline HFpEF (43.9 ± 6.9/100 patient-years) compared to HFmrEF (65.9 ± 3.8/100 patient-years) and HFrEF (93.4 ± 4.8/100 patient-years). Although HFpEF patients had lower mortality and HF hospitalization post-CABG compared to patients with a lower ejection fraction, they experienced the highest rates of future myocardial infarction., Conclusion: Although HFpEF patients with CAD have greater short-term risk post-CABG, their long-term survival is comparable to controls. However, they are at increased risk for HF hospitalizations and myocardial infarction. These data support the safety of CABG in HFpEF patients and suggest continuum of mortality risk for ischaemic HF when stratified by baseline ejection fraction before revascularization., (© 2022 European Society of Cardiology.)

Aims: End-stage heart failure necessitating evaluation for heart transplantation is increasingly recognized in arrhythmogenic right ventricular cardiomyopathy (ARVC). These patients present unique challenges in pre-transplant and peri-transplant management given their predominantly right ventricular (RV) failure and propensity for ventricular arrhythmias. We sought to utilize a tertiary ARVC referral and heart transplant centre experience to describe management of a series of patients with ARVC undergoing heart transplantation at our centre., Methods and Results: We queried the Johns Hopkins ARVC Registry for all patients who underwent heart transplantation and further studied the subset undergoing transplantation at the Johns Hopkins Hospital. Patient demographics, clinical characteristics, and pre-transplant clinical course were obtained from the registry and electronic medical records. Of the 532 patients in the ARVC Registry, 63 (12%) underwent heart transplantation. Nine (six male) of these patients both had known ARVC prior to transplant and were transplanted at Johns Hopkins Hospital between 2006 and 2020 at a mean age of 42 ± 14 years old. Pathogenic ARVC genetic variants were identified in six (67%) patients, all of whom had variants in the plakophilin-2 (PKP2) gene. RV failure was universal with median right atrial to pulmonary capillary wedge pressure (RA/PCWP) ratio of 1.4 [interquartile range (IQR) 1.2-1.5] and median right ventricular stroke work index (RVSWI) of 0 g·m/m 2 /beat (IQR 0-0.3). Six had a history of catheter ablation for ventricular arrhythmia with five of the six having at least three ablations. Transplant evaluation was initiated an average of 344 ± 407 days after first developing heart failure symptoms. The most common bridge to transplant support included inotropes (n = 3) and extracorporeal membrane oxygenation (ECMO) (n = 2). Contraindication to inotropes or mechanical support was common due to ventricular arrhythmia and RV predominant cardiomyopathy., Conclusions: Heart transplantation is a curative treatment for ARVC, but due to frequent ventricular arrhythmias and RV predominant pathology, patients require unique considerations in regard to timing of evaluation, haemodynamic support options, and wait listing qualification., (© 2021 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Angiotensin receptor-neprilysin inhibitors (ARNIs) greatly benefit functional capacity and longevity in heart failure with reduced ejection fraction (HFrEF). Angiotensin receptor-neprilysin inhibitors remain underutilized and unstudied, however, in left ventricular assist device (LVAD) recipients, in spite of their underlying HFrEF. In this case series, we studied the feasibility and short-term efficacy of ARNI utilization in 21 LVAD patients. Angiotensin receptor-neprilysin inhibitor initiation was successful in most, resulting in significant consolidation of blood pressure (BP) medical management and marked improvements in both functional capacity and diuretic requirements. Angiotensin receptor-neprilysin inhibitors are safe, feasible, and within a short timeframe benefit BP and heart failure control in LVAD recipients., Competing Interests: Disclosure: The authors have no conflicts of interest to report., (Copyright © ASAIO 2021.)

Background: Whether rhythm control for post-operative atrial fibrillation after cardiac surgery (POAF) is superior to rate control in patients with heart failure or systolic dysfunction (HF) is not known., Methods: We performed a post-hoc analysis of a trial by the Cardiothoracic Surgical Trials Network, which randomized patients with POAF after cardiac surgery to rate control or rhythm control with amiodarone/cardioversion. We assessed subgroups of trial participants defined by heart failure/cardiomyopathy history or left ventricular ejection fraction (LVEF) < 50%. We conducted a stratified analysis in patients with and without HF to explore outcomes of rhythm versus rate control strategy., Results: Of 523 subjects with POAF after cardiac surgery, 131 (25%) had HF. 49% of HF patients were randomized to rhythm control. In HF patients, rhythm control was associated with less atrial fibrillation within the first 7 days. There were no differences in rhythm at 30- and 60-day follow-up. In the HF group, there were significantly more subjects with AF < 48 hours in the rhythm control group compared to rate control group- 68.8% compared to 46.3%, P=0.009. By comparison, in the non-HF stratum, 54.4% of the rate control group had AF < 48 hours compared to 63.5% of the rhythm control group (P=0.067).), though there was no significant interaction of heart failure with cardiac rhythm at 7 days (Pinteraction 0.16)., Conclusion: Rhythm control for HF patients with POAF after cardiac surgery increases early restoration of sinus rhythm. Rate and rhythm control are both reasonable for HF patients with AF after cardiac surgery., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The use of left ventricular assist devices (LVADs) has been increasing in the last decade, along with the number of patients with advanced heart failure refractory to medical therapy. Ischemic stroke and intracranial hemorrhage remain the leading causes of morbidity and mortality in LVAD patients. Despite the common occurrence and the significant outcome impact, underlying mechanisms and management strategies of stroke in LVAD patients are controversial. In this article, we review our current knowledge on pathophysiology and risk factors of LVAD-associated stroke, outline the diagnostic approach, and discuss treatment strategies., Competing Interests: None declared., (Thieme. All rights reserved.)

Background: With the implementation of the new heart allocation system, heart transplantation teams are prompted to reevaluate management of patients requiring mechanical circulatory support. The purpose of our study is to compare the outcomes of patients supported with extracorporeal membrane oxygenation (ECMO) before transplantation., Methods: The United Network for Organ Sharing database was queried for all adult patients (aged 18 years or more) who required support with ECMO before heart transplantation from 2001 to 2018. Patients were stratified into patients who did not require ECMO before transplantation, who were weaned off ECMO before transplantation, who were bridged immediately to transplantation from ECMO, and who were bridged to a left ventricular assist device (LVAD) before transplantation. Demographics and outcomes including 1-year survival, postoperative stroke, postoperative renal failure requiring dialysis, episodes of rejection, and graft failure were compared., Results: Overall, 29,370 patients did not require ECMO before transplantation, 101 patients were weaned off ECMO before transplantation, 118 were bridged from ECMO directly to transplantation, and 55 patients were successfully bridged from ECMO to LVAD before transplantation. Kaplan-Meier survival estimates found a statistically significant decrease in 1-year survival for patients who were bridged from ECMO to transplantation compared with patients who were bridged to LVAD before subsequent transplantation (P < .001)., Conclusions: Our study suggests bridging ECMO patients to an LVAD before transplantation will result in improved 1-year survival compared with patients bridged to immediate transplantation. With the new heart allocation system, continued evaluation of outcomes is required to inform management strategies., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Heart transplantation is the mainstay of treatment for patients in end-stage heart failure. This study sought to contrast survival after transplantation with that of the general population to quantify standardized mortality rates using a nested case-control study design., Methods: Control subjects were noninstitutionalized inhabitants of the United States identified through the National Longitudinal Mortality study. Case subjects were adults who underwent heart transplantation between 1990 and 2007 and identified through the Organ Procurement and Transplantation Network. Propensity-matching (5:1, nearest neighbor, caliper = 0.1) was utilized to identify suitable control subjects based on age, sex, race, and state of permanent residency. The primary study endpoint was 10-year survival., Results: In all, 31,883 heart transplant recipients were matched to 159,415 noninstitutionalized residents of the United States. The 10-year survival of heart transplant recipients was 53%. The population expected mortality rate was 15.9 deaths per 100 person-years with an observed rate of 45.1 deaths per 100 person-years (standardized mortality rate [SMR] 2.84; 95% confidence interval, 2.82 to 2.87). The broadest gaps between observed and expected survival were evident in female (SMR 3.63), black (SMR 3.67), and Hispanic (SMR 4.12) recipients. Standardized mortality ratios declined over time (1990 to 1995, 3.09; 1996 to 2000, 2.90; 2001 to 2007, 2.58). The long-term standardized survival of older recipients was closest to that expected for their age., Conclusions: Heart transplant recipients have considerable long-term survival and have a threefold higher standardized long-term mortality rate than that of the noninstitutionalized population. Long-term mortality rates have consistently declined over time and will likely continue to decrease., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Survival after heart transplantation is typically reported only in terms of overall survival. Conditional survival may provide prognostic information for patients after surviving a given period. This study sought to provide an analysis of conditional survival in heart transplantation., Methods: Data from 29,000 patients who underwent heart transplantation between 2002 and 2016 were analyzed from the Organ Procurement and Transplantation Network database, and 5-year conditional survival rates were calculated according to age, sex, race, renal function, and hepatic function at transplantation., Results: As time from transplantation increased from 0 to 5 years, the 5-year observed conditional survival changed from 74% to 82% for ages younger than 40 years, 79% to 82% for ages 40 to 49, 79% to 78% for ages 50 to 60, and 75% to 70% for ages older than 60 at transplantation. Conditional survival peaked at 1 and 2 years after transplantation for most subgroups. In recipients younger than 40 years, men had slightly higher conditional survival than women (absolute difference, 3%-4%). In recipients older than 60 years, women had slightly higher conditional survival (absolute difference, 1%-4%). Black recipients had lower survival than white and Hispanic recipients for nearly all time points. Recipients younger than 40 years with the worst renal (65% to 88%) and hepatic function (66% to 83%) at transplantation experienced the largest increase in conditional survival., Conclusions: The conditional survival of patients who undergo heart transplantation changes substantially over time. The largest increases in conditional survival are in young patients with impaired renal and hepatic function. Conditional survival can provide more accurate prognostic information for heart recipients who survive a given period after transplantation., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The utilization of multiorgan transplantation in cardiac transplantation has steadily increased over the past several years. We sought to characterize the trends and outcomes in simultaneous heart and other organ transplantation compared with heart transplantation alone., Methods: The United Network for Organ Sharing database was queried for all adult patients (age ≥ 18 y) who underwent isolated heart transplantation or simultaneous heart-lung or heart-kidney transplantation from 1987-2016. Patients were stratified into 3 equal time intervals. Demographics and postoperative outcomes were compared., Results: A total of 58,060 patients were identified with a distribution based on era. Dual organ recipients had more factors associated with increased operative risk including higher rates of diabetes, pulmonary hypertension, intensive care unit admissions, and dialysis prior to transplantation. Heart-lung and heart-kidney recipients had decreased 1-year survival compared with isolated heart recipients from 2007-2016. However, heart-kidney recipients had significantly increased 5-year post-transplantation survival compared with isolated heart recipients with impaired renal function. For isolated heart transplants and heart-lung transplants, 5-year survival rates improved over time, whereas 5-year survival for heart-kidney recipients did not improve with time., Conclusions: We found a significantly increased 5-year survival rate for heart-kidney transplant recipients compared with isolated heart transplant recipients with renal impairment. Lack of improvement in 5-year postoperative outcomes for heart-kidney recipients in the setting of higher-risk pretransplant clinical characteristics suggests decreased selectivity regarding heart-kidney recipients. Continued scrutiny and evaluation of postoperative outcomes are required to ensure just and appropriate utilization of organs., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

We report a case of intracranial hypertension presenting with bradycardia as the only component of Cushing's triad in a patient on extracorporeal membrane oxygenation. A 41-year-old woman with recurrent driveline infections of HeartMate-II had sternotomy and debridement that was complicated by right ventricular failure requiring veno-arterial extracorporeal membrane oxygenation. Patient was comatose and acute onset of bradycardia occurred without any change in blood pressure or respiration. Computed tomography of brain demonstrated an uncal herniation from diffuse cerebral edema. Acute onset of bradycardia in comatose patients may be the sole component of Cushing's triad in laminar flow circulatory support.

Objectives: We evaluated the impact of preoperative liver function on early and 1-year postoperative outcomes in patients supported with a left ventricular assist device (LVAD) and subsequent evolution of liver function markers., Methods: A retrospective multicentre cohort study was conducted, including all patients undergoing continuous-flow LVAD implantation. The Model for End-stage Liver Disease (MELD) score was used to define liver dysfunction., Results: Overall, 290 patients with an LVAD [78% HeartMate II, 15% HVAD and 7% HeartMate 3, mean age 55 (18), 76% men] were included. Over 40 000 measurements of liver function markers were collected over a 1-year period. A receiver operating characteristic curve analysis for the 1-year mortality rate identified the optimal cut-off value of 12.6 for the MELD score. Therefore, the cohort was dichotomized into patients with an MELD score of less than or greater than 12.6. The early (90-day) survival rates in patients with and without liver dysfunction were 76% and 91% (P = 0.002) and 65% and 90% at 1 year, respectively (P < 0.001). Furthermore, patients with preoperative liver dysfunction had more embolic events and more re-explorations. At the 1-year follow-up, liver function markers showed an overall improvement in the majority of patients, with or without pre-LVAD liver dysfunction., Conclusions: Preoperative liver dysfunction is associated with higher early 90-day and 1-year mortality rates after LVAD implantation. Furthermore, liver function improved in both patient groups. It has become imperative to optimize the selection criteria for possible LVAD candidates, since those who survive the first year show excellent recovery of their liver markers., (© The Author(s) 2019. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: The use of left ventricular assist devices (LVADs) as a bridge to heart transplantation has increased rapidly over the last 2 decades. We aim to explore the effect of pretransplant systemic and device-related complications on posttransplant survival for patients bridged with LVADs., Materials and Methods: The United Network of Organ Sharing (Organ Procurement and Transplantation Network) database was queried for all adult heart transplant recipients (aged ≥ 18 y) transplanted from April 1, 2015, to June 31, 2018. Device-related complications included thrombosis, device infection, device malfunction, life-threatening arrhythmia, and other device complications. Systemic complications included a new dialysis need or ventilator dependence between the time of listing and transplantation, transfusion, or systemic infection requiring treatment with intravenous antibiotics within 2 wk of transplantation., Results: A total of 2131 patients were identified as requiring LVAD support before transplantation. LVAD patients had high rates of preoperative systemic complications (53%) and high rates of device-related complications (42.7% experienced at least one device-related complication). Kaplan-Meier analysis revealed a significantly decreased 1-y survival for LVAD patients bridged to transplantation who experienced a pretransplant systemic complication (P = 0.041). Interestingly, preoperative device-related complications had no effect on 1-y posttransplantation survival (P = 0.93). Multivariate Cox modeling revealed that systemic complications were associated with a significantly increased risk of posttransplant mortality for LVAD patients (hazard ratio 1.45; P = 0.033)., Conclusions: Recipients who suffered a systemic complication while awaiting heart transplantation experienced higher short-term mortality rates. Device-related complications do not appear to impact posttransplantation outcomes., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Aims: Heart failure (HF) patients commonly experience symptoms primarily during elevated heart rates, as a result of physical activities or stress. A main determinant of diastolic passive tension, the elastic sarcomeric protein titin, has been shown to be associated with HF, with unresolved involvement regarding its role at different heart rates. To determine whether titin is playing a role in the heart rate (frequency-) dependent acceleration of relaxation (FDAR). W, we studied the FDAR responses in live human left ventricular cardiomyocytes and the corresponding titin-based passive tension (TPT) from failing and non-failing human hearts., Methods and Results: Using atomic force, we developed a novel single-molecule force spectroscopy approach to detect TPT based on the frequency-modulated cardiac cycle. Mean TPT reduced upon an increased heart rate in non-failing human hearts, while this reduction was significantly blunted in failing human hearts. These mechanical changes in the titin distal Ig domain significantly correlated with the frequency-dependent relaxation kinetics of human cardiomyocytes obtained from the corresponding hearts. Furthermore, the data suggested that the higher the TPT, the faster the cardiomyocytes relaxed, but the lower the potential of myocytes to speed up relaxation at a higher heart rate. Such poorer FDAR response was also associated with a lesser reduction or a bigger increase in TPT upon elevated heart rate., Conclusions: Our study established a novel approach in detecting dynamic heart rate relevant tension changes physiologically on native titin domains. Using this approach, the data suggested that the regulation of kinetic reserve in cardiac relaxation and its pathological changes were associated with the intensity and dynamic changes of passive tension by titin., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2019. For permissions, please email: journals.permissions@oup.com.)

Background: Left ventricular assist devices (LVADs) are the most common mode of circulatory support for patients awaiting heart transplantation. Unfortunately, a fraction of these patients require pump exchange during their course for pump-related adverse events. This study examined whether LVAD exchanges affect posttransplantation outcomes., Methods: This study focused on adult patients in the Organ Procurement and Transplantation Network database who were bridged to transplant with a LVAD implanted between 2007 and 2017. Patients who underwent LVAD exchange were compared with those supported with a single device. The primary end point was all-cause mortality at 1, 2, and 5 years after transplantation. The impact of device exchange on risk-adjusted outcomes was examined using Cox proportional hazards models., Results: Among 8239 patients who met the inclusion criteria, there were 611 pump exchanges in 560 patients (7% of recipients). The pump exchange rate was 6.24 events per 100 patient-years. Survival at 5 years was lower for those who underwent LVAD exchange (69.4% vs 77.5%, log-rank P = .027). This finding was similar for risk-adjusted 5-year mortality (hazard ratio, 1.36; 95% confidence interval, 1.11 to 1.67; P = .003). Subgroup analysis revealed lower 5-year survival for female recipients who underwent LVAD exchange (55.4% vs 79.7%, log-rank P < .001). The interaction between female sex and LVAD exchange was associated with increased risk-adjusted 5-year mortality (hazard ratio, 1.65; 95% confidence interval, 1.05 to 2.59; P = .030)., Conclusions: Recipients who underwent pump exchange while awaiting heart transplantation had a higher mortality compared with those on a primary device. Subgroup analysis revealed a marked increase in mortality of female recipients who experienced LVAD exchange., (Copyright © 2020 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Left ventricular assist devices (LVADs) are an effective therapy in bridging patients with end-stage heart failure to heart transplantation. The aim of this study was to identify the role of race in survival of patients bridged to heart transplantation with a LVAD., Methods: The United Network of Organ Sharing database was queried for all adult heart transplant recipients (age 18 years or older) who were bridged to transplantation with a LVAD from 2005 to 2018. Patients were stratified based on their race, with whites as the reference group. Demographic characteristics, 5-year survival, and graft failure after transplantation were assessed with χ 2 test, analysis of variance, Kaplan-Meier survival analyses, log-rank tests, and Cox proportional hazards modeling or logistic regression modeling as appropriate., Results: Patients (N = 6476) successfully bridged with a LVAD to heart transplantation were identified. There were 4263 whites, 1536 African Americans, 508 Hispanics, and 169 Asians. Compared with whites, African Americans had higher body mass indexes, were more likely to be women, pay with private insurance, and be working for income at the time of transplantation. African Americans were found to have increased odds of graft failure (odds ratio 1.27, P = .048) compared with whites. In addition, African Americans were found to have increased risk of mortality at 5 years (hazard ratio 1.26, P = .003)., Conclusions: The African American race is associated with increased rates of graft failure after transplantation and decreased 5-year survival compared with the white race. Given these findings, directed clinical attention may be warranted in African American patients bridged to heart transplantation with a LVAD., (Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The use left ventricular assist devices (LVAD) as a bridge-to-transplant (BTT) has become a common modality to treat end-stage heart failure. We sought to examine the impact of BTT on long-term survival and quality of life after heart transplant. The population was all adult patients undergoing isolated heart transplantation in the United States between 2007 and 2017. Inclusion criteria covered BTT patients with a LVAD (only Heartmate II [HMII] or HeartWare Ventricular Assist System [HVAD]) and compared these with patients undergoing de novo heart transplantation. Our primary end-point was survival at 1, 2, and 5 years. Secondary end-points were functional status, return to work, and rates of hospital readmission and graft rejection. Unconditional and conditional survival was estimated with the Kaplan-Meier method. The independent influence of BTT on risk-adjusted mortality was determined using Cox proportional hazards models. In this period, 5,584 patients were bridged with an LVAD and 12,295 underwent de novo transplantation. Unconditional survival was 2% higher in de novo patients at 1, 2, and 5 years. After risk adjustment, BTT was associated with increased mortality at each time point. Unadjusted 5 year survival, conditional on 90 day survival, was similar between groups (82.6% vs. 83.4%; p = 0.15). Functional status, return to work, and unadjusted rates of hospital readmission and graft rejection were similar at 1, 2, 5 years. Bridge-to-transplant with LVADs provides excellent survival and similar quality of life to that of patients undergoing de novo heart transplantation. Bridge-to-transplant patients experience a slightly higher mortality rate within 90 days of transplantation.

Background: Left ventricular assist devices are increasingly used as bridge-to-transplantation in eligible patients. The HeartMate 3 (HM3; Abbott Laboratories, Abbot Park, IL) is the latest device to obtain US Food and Drug Administration approval as bridge-to-transplantation. This study examines early outcomes of transplant recipients after HM3 in comparison with recipients bridged with the HeartMate 2 (HM2; Abbott Laboratories) and HeartWare Ventricular Assist System (HVAD; Medtronic, Minneapolis, MN) devices., Methods: Using the Organ Procurement and Transplantation Network database, we identified all adult patients who were slated for bridge-to-transplantation with a continuous-flow left ventricular assist devices (HM2, HVAD, or HM3) between April 1, 2015 and January 31, 2018. The primary endpoint was all-cause mortality 6 months after transplantation. The independent influence of the bridging device on outcomes was determined using Cox proportional hazard models., Results: Patients (N = 1,978) were successfully bridged to transplantation with the HM2 (n = 881), HVAD (n = 920), or HM3 (n = 177) device. Six-month mortality rates were similar across these devices (HM2, 5.9%; HVAD, 7.7%; HM3, 4.7%; log-rank p = 0.30). On average HM2 patients were on a left ventricular assist device for 2 months longer (p < 0.01). The HVAD had the lowest rate of device exchange before transplant (p = 0.01). The HM3 had no events of pump thrombosis (p < 0.01). HVAD patients had the lowest rate of device malfunction before to transplant (p < 0.01). Panel reactive antibodies at the time of transplantation were lower for HM3 patients (p < 0.01); however rates of graft rejection at 6 months were not different (p = 0.25)., Conclusions: The HM3 device provides excellent early outcomes as a bridge to transplantation and may be associated with a reduction in comorbidities. Longer follow-up is needed to better define differences between durable left ventricular assist devices., (Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Sensitization has been associated with worse outcomes following heart transplantation (HTx). The use of ventricular assist devices (VAD) is a risk factor for the development of sensitization. We investigated the impact of left ventricular assist devices (LVAD) and sensitization in HTx recipients., Methods: We queried the UNOS database for all heart transplants performed from January 2000 through December 2016. Patients were considered highly sensitized and included if panel-reactive antibody (PRA) activity was 25% or higher. Patients were separated by pretransplant LVAD utilization and subgroup analysis was performed by device type (HeartMate II or HeartWare). Outcomes included Kaplan-Meier survival and episodes of rejection within 1 year of HTx., Results: Of 18 009 recipients, 2434 (14%) were highly sensitized. 1055 (43.3%) were bridged with a VAD. In multivariate analysis, LVAD use did not impact 1-year (hazards ratio [HR], 1.30; P = 0.052) or 5-year survival (HR, 1.18; P = 0.112) in highly sensitized recipients. Furthermore, episodes of rejection were not affected by LVAD status (P = 0.765). Of the 1055 sensitized LVAD-bridged transplant recipients, 624 (59%) were implanted with a HeartMate II and 99 (9.4%) were bridged with a HeartWare device. In multivariate analysis, no differences were observed in 1-year survival (HR, 0.86; P = 0.664), 5-year survival (HR, 1.35; P = 0.209), or episodes of rejection (P = 0.497)., Conclusions: The use of ventricular assist devices did not impact survival or rejection within 1 year of HTx in highly sensitized patients. Highly sensitized recipients have similar outcomes regardless of prior LVAD support or type of LVAD used as a bridge to transplantation., (© 2019 Wiley Periodicals, Inc.)

Aims: The time course of changes in pulmonary artery (PA) pressure due to left ventricular assist devices (LVADs) is not well understood. Here, we describe longitudinal haemodynamic trends during the peri-LVAD implantation period in patients previously implanted with a remote monitoring PA pressure sensor., Methods and Results: We retrospectively studied PA pressure trends in patients implanted with CardioMEMS™ PA pressure sensor between October 2007 and March 2017 who subsequently had an LVAD procedure. Data are presented as mean ± standard deviation, and P-values are calculated using standard t-test with equal variance. Among 436 patients in cohort, 108 (age 58 ± 11 years, 82% male) received an LVAD and 328 (age 60 ± 13 years, 70% male) did not. The mean PA pressure at sensor implant was higher by 29% (P < 0.001) among patients who later received LVAD. Mean PA pressure 6 months prior to LVAD implant was 35.5 ± 8.5 mmHg, increasing to 39.4 ± 9.9 mmHg (P = 0.04) at 4 weeks before LVAD, and then decreasing 27% to 28.8 ± 8.4 mmHg (P < 0.001) at 3 months post-implant and stabilizing at 31.0 ± 9.4 mmHg at 1 year., Conclusions: Patients who later receive LVADs have higher PA pressures at sensor implant and show a further increase leading up to LVAD implantation. There is a significant reduction of PA pressures post-LVAD implantation that persists long term. PA pressure monitoring may aid in the clinical decision making of timing for LVAD implantation and in management of LVAD patients., (© 2018 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.)

Aims: Heart failure (HF) is a prevalent disease that is considered the foremost reason for hospitalization in the United States. Most protein kinases (PK) are activated in heart disease and their inhibition has been shown to improve cardiac function in both animal and human studies. However, little is known about the direct impact of PKA and PKC inhibitors on human cardiac contractile function., Material and Methods: We investigated the ex vivo effect of such inhibitors on force as well as on kinetics of left ventricular (LV) trabeculae dissected from non-failing and failing human hearts. In these experiments, we applied 0.5 μM of H-89 and GF109203X, which are PKA and PKC inhibitors, respectively, in comparison to their vehicle DMSO (0.05%)., Key Findings and Conclusion: Statistical analyses revealed no significant effect for H-89 and GF109203X on either contractile force or kinetics parameters of both non-failing and failing muscles even though they were used at a concentration higher than the reported IC 50 s and K i s. Therefore, several factors such as selectivity, concentration, and treatment time, which are related to these PK inhibitors according to previous studies require further exploration., (Copyright © 2018 Elsevier Inc. All rights reserved.)

In this study, we investigated the quantitative and qualitative role of the sarcoplasmic reticulum (SR) in the regulation of the force-frequency relationship (FFR). We blocked the function of SR with cyclopiazonic acid (CPA) and ryanodine and measured twitch kinetics and developed force at various stimulation frequencies in nonfailing and failing intact human right ventricular trabeculae. We found that developed forces are only slightly reduced upon SR blockade, while the positive FFR in nonfailing trabeculae and negative FFR in failing trabeculae were both preserved. The contraction kinetics (dF/dt, dF/dt/F, and time to peak), however, were significantly slower at all frequencies tested. Kinetics of first 50% of relaxation (RT50) was not affected by SR blockade. Kinetics of entire relaxation process (RT90) was overall slower at low frequencies, but not at high frequencies. From our findings, we conclude that the SR is not essential for FFR, and its role in regulation of FFR lies mostly in contraction kinetics. Unlike small rodents, human myocardium contractile function is near-normal in absence of a functional SR with little changes in contractile force, and with preservation with the main regulation of FFR., (© 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Severe right ventricular (RV) failure is a significant cause of morbidity and mortality, with an in-hospital mortality rate up to 70% to 75%. Medical management is employed and is successful for most of these patients. However, a small percentage of patients will continue to have persistent RV failure, for which mechanical support is used for management., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Recent studies report that a single subtype of α1-adrenergic receptor (α1-AR), the α1A-subtype, mediates robust cardioprotective effects in multiple experimental models of heart failure, suggesting that the α1A-subtype is a potential therapeutic target for an agonist to treat heart failure. Moreover, we recently found that the α1A-subtype is present in human heart. The goal of this study was to assess the inotropic response mediated by the α1A-subtype in human myocardium, and to determine whether the response is downregulated in myocardium from failing human heart. We measured in vitro contractile responses of cardiac muscle preparations (trabeculae) isolated from the right ventricle from nonfailing and failing human hearts. Addition of the α1A-subtype agonist A61603 (100 nM) resulted in a large positive inotropic response (force increased ≈ 2-fold). This response represented ≈70% of the response mediated by the β-adrenergic receptor agonist isoproterenol (1 μM). Moreover, in myocardium from failing hearts, α1A-subtype responses remained robust, and only slightly reduced relative to nonfailing hearts. We conclude that α1A-subtype-mediated inotropy could represent a significant source of inotropic support in the human heart. Furthermore, the α1A-subtype remains functional in myocardium from failing human hearts and thus, might be a therapeutic target to support cardioprotective effects in patients with heart failure.

Background: In patients with end-stage heart failure, the primary etiology often originates in the left ventricle, and eventually the contractile function of the right ventricle (RV) also becomes compromised. RV tissue-level deficits in contractile force and/or kinetics need quantification to understand involvement in ischemic and non-ischemic failing human myocardium., Methods and Results: The human population suffering from heart failure is diverse, requiring many subjects to be studied in order to perform an adequately powered statistical analysis. From 2009-present we assessed live tissue-level contractile force and kinetics in isolated myocardial RV trabeculae from 44 non-failing and 41 failing human hearts. At 1 Hz stimulation rate (in vivo resting state) the developed active force was not different in non-failing compared to failing ischemic nor non-ischemic failing trabeculae. In sharp contrast, the kinetics of relaxation were significantly impacted by disease, with 50% relaxation time being significantly shorter in non-failing vs. non-ischemic failing, while the latter was still significantly shorter than ischemic failing. Gender did not significantly impact kinetics. Length-dependent activation was not impacted. Although baseline force was not impacted, contractile reserve was critically blunted. The force-frequency relation was positive in non-failing myocardium, but negative in both ischemic and non-ischemic myocardium, while the β-adrenergic response to isoproterenol was depressed in both pathologies., Conclusions: Force development at resting heart rate is not impacted by cardiac pathology, but kinetics are impaired and the magnitude of the impairment depends on the underlying etiology. Focusing on restoration of myocardial kinetics will likely have greater therapeutic potential than targeting force of contraction., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Left ventricular assist device (LVAD) therapy has emerged as an increasingly vital facet of the treatment algorithm for advanced heart failure. Growing experience with LVAD support has led to substantial improvements in outcomes, with 1-year survival rates approaching that of cardiac transplantation. These therapeutic refinements have engendered growing interests in the potential for expanding the clinical indications for LVAD therapy to patients with less advanced heart failure. The primary obstacles to this evolution of care center largely on the prevention and/or management of the adverse events associated with LVAD therapy along with patient preference. Many programs also face the mounting difficulty of balancing quality outcomes with the increased volume of implants. During the recently assembled Users Meeting organized by St. Jude Medical, heart failure clinicians from nearly 50 LVAD implanting centers discussed these and other challenges and controversies impacting the field. The present review summarizes the key insights gleaned from this meeting., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Long-term survivors after implantation of left ventricular assist devices (LVADs) are increasing in prevalence. We describe the characteristics and outcomes in patients surviving longer than 4 years on LVAD support., Methods: We performed a multicenter, retrospective analysis of patients surviving at least 4 years on continuous-flow LVAD (CF-LVAD) support with a HeartMate II at centers participating in the Evolving Mechanical support Research Group., Results: Between 2005 and 2010, 156 long-term survivors were identified with a mean survival of 7.1 years (95% confidence interval: 6.7 to 7.5 years). The mean age was 58.2 ± 15.2 years and 30.1% were women. Readmission rate was low at 1.1 events per patient per year with the most common reasons leading to readmission being infection (0.10 readmissions per patient per year) and gastrointestinal bleeding (0.07 readmissions per patient per year). Two years after implantation, 97% of patients were either New York Heart Association functional class I or II, with 92% at 4 years., Conclusions: Patients surviving 4 years on CF-LVAD support can anticipate ongoing long-term survival with sustained improvements in functionality and low rates of rehospitalization., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: Thromboembolic and bleeding events are potential complications following left ventricular assist device implantation. A tight control of the international normalized ratio (INR) is believed to be crucial in the reduction of postimplant complications. There is significant variability among institutions as to whether a device implanting centre should be managing the INR. In this study, we evaluated the effect of INR management strategies in maintaining a therapeutic INR., Methods: A retrospective review was utilized to identify patients implanted with either the HeartMate II or the HeartWare HVAD between January 2011 and February 2016. Patients were stratified into 4 groups based on the post-discharge INR management strategy: outside hospital system anticoagulation clinic, outside hospital primary care provider, implanting centre anticoagulation clinic or implanting centre ventricular assist device office. The INR data were collected and analysed for both the early (discharge, 7, 14, 21 and 30 days) and late (3, 6, 9 and 12 months) postoperative periods., Results: There were 163 patients identified during the study period who met the study inclusion criteria: 49 (30%) patients were managed by an outside hospital system anticoagulation clinic, 59 (36.2%) patients by an outside hospital physician/primary care provider, 22 (13.5%) patients by the implanting centre anticoagulation clinic and 33 (20.2%) patients by the implanting centre ventricular assist device office. There were no statistically significant differences found between management strategies across all time points., Conclusions: There was no statistically significant difference found between the management strategies examined. Regardless of the chosen INR management strategy, patients have similar INR values and postoperative outcomes., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

More than 5 million Americans suffer from heart failure and more than 250,000 die annually. Cardiac surgery, as applied to advanced heart failure, has evolved significantly in the past 50 years. Current therapeutic interventions are focused on the appropriate assessment of myocardial dysfunction as a means to select the right patient for the appropriate procedure using state-of-the-art myocardial viability testing and metabolic testing to determine candidacy for conventional interventions, mechanical devices, or transplant. Advances in mechanical circulatory support with more efficient and less morbid ventricular assist devises offer the potential to change the trajectory of this growing epidemiologic dilemma., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: Early right-sided heart failure (RHF) after left ventricular assist device (LVAD) implantation is associated with increased mortality, but little is known about patients who develop late RHF (LRHF). We evaluated the incidence, risk factors, and clinical impact of LRHF in patients supported by axial-flow LVADs., Methods: Data were analyzed from 537 patients enrolled in the HeartMate II (HM II; Thoratec/St. Jude) destination therapy clinical trial. LRHF was defined as the development of clinical RHF accompanied by the need for inotropic support occurring more than 30 days after discharge from the index LVAD implant hospitalization. Clinical variables, quality of life, rehospitalizations, and survival were compared between patients with and without LRHF., Results: LRHF developed in 41 patients (8%), with a median time to LRHF of 480 days. A higher preoperative blood urea nitrogen and increased central venous pressure-to-pulmonary capillary wedge pressure ratio were independent predictors of LRHF. The Michigan and HMII RHF risk scores were both associated with an increased likelihood of LRHF (p < 0.05). Patients with LRHF had worse quality of life according to the Kansas City Cardiomyopathy Questionnaire (61 ± 26 vs 70 ± 21; p < 0.05), poorer functional capacity by 6-minute walk distance (275 ± 189 m vs 312 ± 216 m; p < 0.05), and more rehospitalizations (6 vs 3; p < 0.001). LRHF was associated with decreased survival (p < 0.001)., Conclusions: LRHF is an important complication in patients with LVADs and is associated with worse quality of life, reduced functional capacity, more frequent hospitalizations, and worse survival compared with those without LRHF., (Copyright © 2016 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: Recommended structured clinical practices including implant technique, anti-coagulation strategy, and pump speed management (PREVENT [PREVENtion of HeartMate II Pump Thrombosis Through Clinical Management] recommendations) were developed to address risk of early (<3 months) pump thrombosis (PT) risk with HeartMate II (HMII; St. Jude Medical, Inc. [Thoratec Corporation], Pleasanton, CA). We prospectively assessed the HMII PT rate in the current era when participating centers adhered to the PREVENT recommendations., Methods: PREVENT was a prospective, multi-center, single-arm, non-randomized study of 300 patients implanted with HMII at 24 participating sites. Confirmed PT (any suspected PT confirmed visually and/or adjudicated by an independent assessor) was evaluated at 3 months (primary end-point) and at 6 months after implantation., Results: The population included 83% men (age 57 years ± 13), 78% destination therapy, and 83% Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) Profile 1-3. Primary end-point analysis showed a confirmed PT of 2.9% at 3 months and 4.8% at 6 months. Adherence to key recommendations included 78% to surgical recommendations, 95% to heparin bridging, and 79% to pump speeds ≥9,000 RPMs (92% >8,600 RPMs). Full adherence to implant techniques, heparin bridging, and pump speeds ≥9,000 RPMs resulted in a significantly lower risk of PT (1.9% vs 8.9%; p < 0.01) and lower composite risk of suspected thrombosis, hemolysis, and ischemic stroke (5.7% vs 17.7%; p < 0.01) at 6 months., Conclusions: Adoption of all components of a structured surgical implant technique and clinical management strategy (PREVENT recommendations) is associated with low rates of confirmed PT., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: Increased numbers of end-stage heart failure patients and improved technology have led to increased use of left ventricular assist devices as a viable alternative to heart transplants. Given the current economic climate, we compared costs of heart transplant versus device placement., Materials and Methods: Medical records of patients who received heart transplants or left ventricular assist devices were cross-referenced with institutional financial data. The device cohort was limited to those receiving durable (not temporary) devices. Index admission, 1-year readmission, and overall 1-year charges were compared using standard statistical methods., Results: Of 184 identified patients with end-stage heart failure surgical therapy, 121 received left ventricular assist devices, 43 had heart transplants, and 20 received left ventricular assist devices as bridge to heart transplant; these latter patients were excluded from our analyses. At index admission, mean charges were $863 433 ± $398 427 for device patients and $725 877 ± $488 685 for transplant patients (P = .05). One-year mean readmission rates were similar (4.65/transplant patient and 4.53/device patient; P = .94), with corresponding 1-year survival rates of 87.8% and 78.0% (P = .04). Total readmission charges during year 1 were $169 732 ± $242 366 for device patients and $201 682 ± $297 565 for transplant patients (P = .08), with corresponding overall charges at 1 year of $1 029 732 ± $450 498 and $927 559 ± $562 404 (P = .49)., Conclusions: During the first year, heart transplant and left ventricular assist device placement have similar costs. Initial index admission costs seem to favor heart transplant, with device pump costs accounting for some of the difference. From a 1-year survival perspective, heart transplant may be more effective; however, with lack of suitable donors, left ventricular assist devices are valuable in the armamentarium of advanced heart failure surgical options.

Concerns exist regarding orthotropic heart transplantation in hepatitis C virus (HCV) seropositive recipients. Thus, a national registry was accessed to evaluate early and late outcome in HCV seropositive recipients undergoing heart transplant. Retrospective analysis of the United Network for Organ Sharing registry (1991 to 2014) was performed to evaluate recipient profile and clinical outcome of patients with HCV seropositive (HCV +ve) and seronegative (HCV -ve). Adjusted results of early mortality and late survival were compared between cohorts. From 23,507 patients (mean age 52 years; 75% men), 481 (2%) were HCV +ve (mean age 52 years; 77% men). Annual proportion of HCV +ve recipients was comparable over the study period (range 1.3% to 2.7%; p = 0.2). The HCV +ve cohort had more African-American (22% vs 17%; p = 0.01), previous left ventricular assist device utilization (21% vs 14%; p <0.01) and more hepatitis B core Ag+ve recipients (17% vs 5%; p <0.01). However, both cohorts were comparable in terms of extracorporeal membrane oxygenator usage (p = 0.7), inotropic support (p = 0.2), intraaortic balloon pump (p = 0.7) support, serum creatinine (p = 0.7), and serum bilirubin (p = 0.7). Proportion of status 1A patients was similar (24% HCV + vs 21% HCV -); however, wait time for HCV +ve recipients were longer (mean 23 vs 19 days; p <0.01). Among donor variables, age (p = 0.8), hepatitis B status (p = 0.4), and Center for Diseases Control high-risk status (p = 0.9) were comparable in both cohorts. At a median follow-up of 4 years, 67% patients were alive, 28% died, and 1.1% were retransplanted (3.4% missing). Overall survival was worse in the HCV+ cohort (64.3% vs 72.9% and 43.2% vs 55% at 5 and 10 years; p <0.01), respectively. Late renal (odds ratio [OR] 1.2 [1 to 1.6]; p = 0.02) and liver dysfunction (odds ratio 4.5 [1.2 to 15.7]; p = 0.01) occurs more frequently in HCV +ve recipients. On adjusted analysis, HCV seropositivity is associated with poorer survival (hazard ratio for mortality 1.4 [1.1 to 1.6]; p <0.001). In conclusion, a small proportion of patients receiving a heart transplant in the United States have hepatitis C. Despite comparable preoperative hepatic function, hepatitis C seropositive recipients demonstrate poorer long-term survival., (Copyright © 2016 Elsevier Inc. All rights reserved.)

β2-Spectrin is critical for integrating membrane and cytoskeletal domains in excitable and nonexcitable cells. The role of β2-spectrin for vertebrate function is illustrated by dysfunction of β2-spectrin-based pathways in disease. Recently, defects in β2-spectrin association with protein partner ankyrin-B were identified in congenital forms of human arrhythmia. However, the role of β2-spectrin in common forms of acquired heart failure and arrhythmia is unknown. We report that β2-spectrin protein levels are significantly altered in human cardiovascular disease as well as in large and small animal cardiovascular disease models. Specifically, β2-spectrin levels were decreased in atrial samples of patients with atrial fibrillation compared with tissue from patients in sinus rhythm. Furthermore, compared with left ventricular samples from nonfailing hearts, β2-spectrin levels were significantly decreased in left ventricle of ischemic- and nonischemic heart failure patients. Left ventricle samples of canine and murine heart failure models confirm reduced β2-spectrin protein levels. Mechanistically, we identify that β2-spectrin levels are tightly regulated by posttranslational mechanisms, namely Ca(2+)- and calpain-dependent proteases. Furthermore, consistent with this data, we observed Ca(2+)- and calpain-dependent loss of β2-spectrin downstream effector proteins, including ankyrin-B in heart. In summary, our findings illustrate that β2-spectrin and downstream molecules are regulated in multiple forms of cardiovascular disease via Ca(2+)- and calpain-dependent proteolysis., (Copyright © 2016 the American Physiological Society.)

Cross-bridge cycling rate is an important determinant of cardiac output, and its alteration can potentially contribute to reduced output in heart failure patients. Additionally, animal studies suggest that this rate can be regulated by muscle length. The purpose of this study was to investigate cross-bridge cycling rate and its regulation by muscle length under near-physiological conditions in intact right ventricular muscles of nonfailing and failing human hearts. We acquired freshly explanted nonfailing (n = 9) and failing (n = 10) human hearts. All experiments were performed on intact right ventricular cardiac trabeculae (n = 40) at physiological temperature and near the normal heart rate range. The failing myocardium showed the typical heart failure phenotype: a negative force-frequency relationship and β-adrenergic desensitization (P < 0.05), indicating the expected pathological myocardium in the right ventricles. We found that there exists a length-dependent regulation of cross-bridge cycling kinetics in human myocardium. Decreasing muscle length accelerated the rate of cross-bridge reattachment (ktr) in both nonfailing and failing myocardium (P < 0.05) equally; there were no major differences between nonfailing and failing myocardium at each respective length (P > 0.05), indicating that this regulatory mechanism is preserved in heart failure. Length-dependent assessment of twitch kinetics mirrored these findings; normalized dF/dt slowed down with increasing length of the muscle and was virtually identical in diseased tissue. This study shows for the first time that muscle length regulates cross-bridge kinetics in human myocardium under near-physiological conditions and that those kinetics are preserved in the right ventricular tissues of heart failure patients., (Copyright © 2015 the American Physiological Society.)

Background: The hyperpolarization-activated current, If, plays an important role in sinoatrial node (SAN) pacemaking. Surprisingly, the distribution of hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in human SAN has only been investigated at the mRNA level. Our aim was to define the expression pattern of HCN proteins in human SAN and different atrial regions., Methods and Results: Entire SAN complexes were isolated from failing (n=5) and nonfailing (n=9) human hearts cardioplegically arrested in the operating room. Three-dimensional intramural SAN structure was identified as the fibrotic compact region around the SAN artery with Connexin 43-negative pacemaker cardiomyocytes visualized in Masson's trichrome and immunostained cryosections. SAN protein was precisely isolated from the adjacent frozen SAN tissue blocks using a 16G biopsy needle. The purity of the SAN protein was confirmed by Connexin 43 immunoblot. All 3 HCN isoform proteins were detected in SAN. HCN1 was predominantly distributed in the human SAN with a 125.1±40.2 (n=12) expression ratio of SAN to right atrium. HCN2 and HCN4 expression levels were higher in SAN than in atria, with SAN to right atrium ratios of 6.1±0.9 and 4.6±0.6 (n=12), respectively., Conclusions: This is the first study to conduct precise 3D molecular mapping of the human SAN by isolating pure pacemaker SAN tissue. All 3 cardiac HCN isoforms had higher expression in the SAN than in the atria. HCN1 was almost exclusively expressed in SAN, emphasizing its utility as a new specific molecular marker of the human SAN and as a potential target of specific treatments intended to modify sinus rhythm., (© 2015 American Heart Association, Inc.)

Claudin-5 is transcriptionally downregulated resulting in dramatically reduced protein levels in human heart failure. Studies in mice have demonstrated that reduced claudin-5 levels occur prior to cardiac damage and far before reduced whole heart function. Therefore, claudin-5 may be a useful early therapeutic target for human heart failure. However, the cell types in which claudin-5 is localized in human heart and from which claudin-5 is reduced in heart failure is not known. The recent identification of claudin-5's interaction with ephrin-B1 in mouse hearts has also not been investigated in non-failing or failing human hearts. In this study we collected human left ventricular mid-myocardium histological samples from 7 non-failing hearts and 16 end-stage failing hearts. Immunoblots demonstrate severe reductions of claudin-5 protein in 14 of 16 failing hearts compared to non-failing controls. Claudin-5 was observed to localize to cardiomyocytes, endothelial cells, and a subset of fibroblasts in non-failing human heart sections. In isolated cardiomyocytes, the transmembrane claudin-5 protein localized in longitudinal striations in lateral membranes. In failing heart, both cardiomyocyte and endothelial claudin-5 localization was severely reduced, but claudin-5 remained in fibroblasts. Absence of claudin-5 staining also correlated with the reduction of the endothelial cell marker CD31. Ephrin-B1 localization, but not protein levels, was altered in failing hearts supporting that claudin-5 is required for ephrin-B1 localization. These data support that loss of claudin-5 in cardiomyocytes and endothelial cells is prevalent in human heart failure. Investigating claudin-5/ephrin-B1 protein complexes and gene regulation may lead to novel therapies., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: This study evaluated whether minority orthotopic heart transplant (OHT) recipients tend to be transplanted at worse performing centers., Methods and Results: OHT recipients between 2000 and 2010 were identified in the United Network for Organ Sharing database and stratified by race. Center performance was evaluated using observed-to-expected mortality ratios that were calculated using validated indexes for recipient and donor risk in OHT. The primary outcome was 1-year post-OHT mortality. A total of 102 centers performed OHT in 18 085 patients. Blacks had higher unadjusted 1-year mortality, which was confirmed after risk adjustment. Blacks had increased risk-adjusted mortality at poor performing centers (observed-to-expected mortality ratio, >1.2; odds ratio, 1.37 [95% confidence interval, 1.12-1.69]; P=0.002) and a strong trend toward increased mortality at excellent performing centers (observed-to-expected mortality ratio, <0.8; odds ratio, 1.42 [95% confidence interval, 0.99-2.02]; P=0.06). A higher proportion of blacks were treated at centers with higher-than-expected mortality (56.4% versus 47.1% whites versus 48.1% Hispanics; P<0.001), a finding that persisted after adjusting for insurance type and highest education level. In addition, there was a positive correlation between the percentage of blacks and observed-to-expected mortality ratios at the center level (r=0.32; P=0.001). In multivariable analysis incorporating immunologic and socioeconomic variables, there was no clear dominant source for the disparities in outcomes of OHT between races., Conclusions: Blacks have a propensity to be transplanted at worse performing centers; however, center effect alone does not explain the mortality difference between ethnicities. Although referral of minorities to better performing centers would improve absolute survival, it would not likely eliminate the racial disparities that exist in OHT outcomes., (© 2015 American Heart Association, Inc.)

The role of I(KCa) in cardiac repolarization remains controversial and varies across species. The relevance of the current as a therapeutic target is therefore undefined. We examined the cellular electrophysiologic effects of I(KCa) blockade in controls, chronic heart failure (HF) and HF with sustained atrial fibrillation. We used perforated patch action potential recordings to maintain intrinsic calcium cycling. The I(KCa) blocker (apamin 100 nM) was used to examine the role of the current in atrial and ventricular myocytes. A canine tachypacing induced model of HF (1 and 4 months, n = 5 per group) was used, and compared to a group of 4 month HF with 6 weeks of superimposed atrial fibrillation (n = 7). A group of age-matched canine controls were used (n = 8). Human atrial and ventricular myocytes were isolated from explanted end-stage failing hearts which were obtained from transplant recipients, and studied in parallel. Atrial myocyte action potentials were unchanged by I(KCa) blockade in all of the groups studied. I(KCa) blockade did not affect ventricular myocyte repolarization in controls. HF caused prolongation of ventricular myocyte action potential repolarization. I(KCa) blockade caused further prolongation of ventricular repolarization in HF and also caused repolarization instability and early afterdepolarizations. SK2 and SK3 expression in the atria and SK3 in the ventricle were increased in canine heart failure. We conclude that during HF, I(KCa) blockade in ventricular myocytes results in cellular arrhythmias. Furthermore, our data suggest an important role for I(KCa) in the maintenance of ventricular repolarization stability during chronic heart failure. Our findings suggest that novel antiarrhythmic therapies should have safety and efficacy evaluated in both atria and ventricles.

Diaphragmatic hernias are a known complication of explanting a left ventricular assist device. The increasing use of left ventricular assist devices has resulted in an increased risk of this complication. We present the case of a patient who presented with diaphragmatic hernias on routine follow-up after a heart transplant. A left thoracotomy was performed to expose and reduce the hernia using a bovine pericardial patch to repair the defect. This biomaterial represents a viable alternative to traditional GORE-TEX patches with the probability of decreased infectious complications.