Pediatric Heart Failure, VADs, Heart Transplant & Relevant Adult Cardiology Topics

Extracorporeal membrane oxygenation (ECMO) before ventricular assist device (VAD) implantation as a "double-bridge" strategy to heart transplantation is often used for the most acutely ill patients with decompensated heart failure. This cohort of patients has worse outcomes than those with primary VAD. Early crossover from ECMO to VAD has shown to have better survival in adults who are double-bridged. This study aims to evaluate the outcomes of early versus late crossover in pediatric patients who were double-bridged using the Advanced Cardiac Therapies Improving Outcomes Network registry. All patients <18 years of age in the Advanced Cardiac Therapies Improving Outcomes Network database who were double-bridged were identified. Patients were categorized into early or delayed crossover groups. Univariate and multivariate Cox regression analysis identified independent risk factors of outcomes. Kaplan-Meier and competing risk analyses assessed survival. Of 1360 patients, 334 (24%) underwent double-bridging. Median ECMO support was 6 days, leading to an early crossover group (≤6 days) of ECMO (n = 168) and a delayed crossover group (>6 days) of ECMO support (n = 166). Univariate analysis showed that patients who were double-bridged were considerably sicker than the primary VAD group. Multivariable analysis revealed that a diagnosis of dilated cardiomyopathy/myocarditis and bridge to candidacy device intent were independent predictors of outcome. Duration of ECMO support/timing of crossover (early vs late) was not independently associated with outcomes. The timing of crossover from ECMO to VAD in pediatric patients subject to the double-bridge strategy does not affect outcomes. Focus on the patient selection and reversibility of risk factors rather than the duration of ECMO support may improve outcomes in this high-risk population.

The Berlin Heart paracorporeal ventricular assist device (VAD) is widely used for bridging pediatric patients to transplantation. Contemporary, multiinstitutional analyses of VAD types used in children and their impact on outcomes are limited. This analysis evaluates multiinstitutional outcomes after cardiac transplantation in patients aged ≤5 years in the following categories: no VAD, Berlin Heart VAD, or other VAD. The United Network for Organ Sharing database was analyzed to evaluate perioperative outcomes and 3-year survival in patients aged ≤5 years undergoing first-time cardiac transplantation (September 6, 2004 to June 30, 2023). The study population comprised 3649 patients (no VAD [n = 2822], Berlin Heart [n = 670], other VAD [n = 157]). Distinct demographic and clinical characteristics were observed among patients bridged with Berlin Heart, including a higher prevalence of congenital heart disease, longer waitlist durations, and higher utilization of extracorporeal membrane oxygenation at transplant. Patients bridged with other VADs exhibited notably higher 3-year mortality compared with both Berlin Heart and no VAD groups. Multivariable analysis identified key risk factors associated with increased mortality, including congenital heart disease and extracorporeal membrane oxygenation at transplant. By highlighting the comparative effectiveness of different VAD types and key risk factors, our study contributes valuable insights in guiding clinical decision-making in this challenging patient population and also provides important information to guide future research.

ABO-incompatible (ABOi) heart transplantation, first performed in infants by West and colleagues in 1996, transformed pediatric heart allocation by challenging longstanding immunologic constraints. Early success of this approach leveraged the developmental immaturity of the neonatal immune system and has since shown comparable short- and long-term outcomes to ABO-compatible (ABOc) transplantation. Over three decades, increasing clinical experience and policy evolution, including broader ABOi eligibility criteria and relaxed titer thresholds, have expanded access to donor hearts and reduced waitlist mortality, particularly among blood group ABO-O candidates. Despite these advances, marked variability persists among centers in the measurement, interpretation, and reporting of ABO antibody titers, directly influencing candidate selection, perioperative management, and post-transplant surveillance. Most assays rely on manual hemagglutination techniques that are subject to significant inter-laboratory and intra-laboratory variability. Emerging single-antigen bead-based methods utilizing the Luminex platform may provide an opportunity for standardized, semi-quantitative assessment of graft-relevant anti-A and -B antibody levels. Perioperative strategies are individualized according to ABO antibody titer, with intraoperative plasma exchange or immunoadsorption typically employed when titers exceed a center-specific level. Standard immunosuppression regimens are generally sufficient, with anti-B cell therapies (e.g. rituximab) reserved for elevated or rebound titers. Long-term outcomes remain excellent, with most patients not producing donor-specific ABO antibodies after ABOi transplant. Most centers perform surveillance biopsies only when rising titers, an uncommon occurrence, are accompanied by graft dysfunction or biopsy-proven antibody-mediated rejection, managed with combinations of plasmapheresis, IVIG, and anti-B cell therapies as indicated. Future multicenter collaborations incorporating standardized reporting and longitudinal follow-up will be critical to optimize candidate selection, refine management algorithms, and further improve utilization and outcomes of ABOi heart transplantation.

Advances in medical management have markedly improved early and late outcomes after pediatric heart transplantation. Although survival data are well established in Western countries, evidence from Asia remains limited. We retrospectively reviewed the records of 75 patients who underwent heart transplantation younger than 18 years and received posttransplant care at The University of Osaka Hospital, Japan, between 2000 and 2024. The cohort included 35 male patients, with a median age of 6 years at transplantation. Forty-six patients (61%) underwent transplantation in Japan and 29 (39%) underwent transplantation in other countries. Underlying diagnoses were dilated cardiomyopathy in 42 patients (56%), restrictive cardiomyopathy in 23 (31%), and congenital heart disease in 4 (5%). Overall survival was 96% at 5 and 10 years, 86% at 15 years. Major posttransplant complications included posttransplant lymphoproliferative disease (n = 9), rejection requiring intensified immunosuppression (n = 14), cardiac allograft vasculopathy (n = 5), and renal failure requiring kidney transplantation or dialysis (n = 9). Among the 38 patients who reached adulthood, 15 (39%) were employed, 14 (37%) were pursuing higher education, and 9 (24%) were neither employed nor in education. Pediatric heart transplantation at our institution yielded long-term survival rates comparable with international registry data. Most patients achieved stable school attendance and successful adult social reintegration.

Left ventricular assist devices remain a major step forward for end-stage heart failure patients awaiting transplantation. We investigated the molecular basis of the longitudinal effect of left ventricular assist device implantation in both ischemic and nonischemic cardiomyopathy patients. The results revealed a common signature of 13 genes associated with glucocorticoid receptor overexpression pretransplantation, independent of the etiology. Four key molecular hub genes from this signature were highlighted, involved respectively in metabolic plasticity (PDK4), limited inflammation (FKBP5 and ZBTB16), and repair (FOXO3). It shows, however, that these pathways contribute to cardiac homeostasis.

Postoperative vasoplegia syndrome (PVS) following cardiac surgery has previously been associated with poor survival. This study aimed to investigate outcomes and predictors of PVS following left ventricular assist device implantation. This was a retrospective study of 190 left ventricular assist device recipients at The Ohio State University. Primary outcomes included hospitalization duration, right-sided heart failure, and mortality. Risk factor evaluation included multivariate analysis of cardiovascular comorbidities and perioperative medication use. Patients were stratified into PVS (n=50, 26.3%) and non-PVS cohorts. On univariate analysis, PVS was associated with male sex (94% versus 67%, p=0.0004) and higher body mass index (32.5 versus 29.0, p=0.0011). Further, PVS was associated with diabetes (60.0% versus 41.4%, p=0.036), higher preoperative hemoglobin A1c levels (6.8% versus 6.3%, p=0.0354), and higher rates of microvascular complications (28.0% versus 12.9%, p=0.014). Preoperatively, patients without PVS were more likely to receive dobutamine (58.6% versus 34.0%, p=0.004) and at higher dosages (2.9 versus 1.9 μg/kg per min, p=0.0196). Primary outcomes, including mortality, were similar between groups. Multivariate analysis demonstrated male sex (OR 9.43 [95% CI, 2.93-43.6]) and higher body mass index (OR 1.11 [95% CI, 1.04-1.18]) as independent risk factors. HeartMate 3 implantation (OR 0.33 [95% CI, 0.10-0.97]) and preimplant dobutamine infusion (OR 0.28 [95% CI, 0.12-0.61]) were protective factors. PVS did not confer inferior outcomes after left ventricular assist device implantation but was associated with male sex and higher body mass index. Preoperative dobutamine was more commonly used in patients without PVS, warranting further investigation.

The Impella 5.5 is FDA-approved for up to 14 days of support in patients with cardiogenic shock, however, its extended use is increasingly employed as a bridge to advanced therapies. To compare outcomes with short-term (≤14 days) vs prolonged (>14 days) Impella 5.5 support in patients with cardiogenic shock. Multiple databases were searched through September 2025 to identify relevant studies, and 5 studies met the inclusion criteria, encompassing total of 1,440 patients. Pooled risk ratios (RRs) with 95% confidence intervals (CI) were calculated using a random-effects meta-analysis in R-software. Prolonged Impella 5.5 support (>14 days) was associated with a higher likelihood of successful bridging to heart transplantation (RR: 1.96, 95% CI: 1.01-3.83; p = 0.049), and with lower in-hospital mortality rate (RR: 0.67, 95% CI: 0.53-0.84; p = 0.011). However, native heart survival or recovery (RR: 0.70, 95% CI: 0.54-0.90; p = 0.026) was significantly lower with prolonged support. There was no significant difference in bridging to durable LVAD between the groups (RR: 0.86; 95% CI: 0.54-1.36, p = 0.28). Prolonged Impella support was associated with higher risks of insertion-site hematoma (RR: 1.55, 95% CI: 1.07-2.24; p = 0.036) and infection (RR: 3.36, 95% CI: 2.71-4.17; p = 0.002), while stroke rates were similar between groups (RR: 1.34; 95% CI: 0.96-1.89; p = 0.074). Extending Impella 5.5 support beyond 14 days in patients with cardiogenic shock appears advantageous for select patients, conferring improved survival and higher likelihood of successful bridging to heart transplantation. However, significantly higher risk of implant-site hematoma and infection necessitates meticulous vascular management, infection-prevention strategies and close clinical surveillance.