Early outcomes of pediatric heart transplantation: Impact of mechanical circulatory support and perioperative challenges. A single-center retrospective study.

Background: Pediatric heart transplantation stays the gold standard treatment for end-stage heart failure, but outcomes are influenced by pre-transplant status and bridging strategies, particularly mechanical circulatory support (MCS). Objectives: To evaluate early outcomes following pediatric heart transplantation and assess the impact of pre-transplant MCS on survival and complications. Methods: We retrospectively analyzed all pediatric patients (<14 years) who underwent orthotopic heart transplantation at a single tertiary center between January 2020 and January 2025. Demographics, pre-transplant support, intraoperative data, and early outcomes were collected. Primary outcome was 30-day survival; secondary outcomes included acute rejection, infection, acute kidney injury (AKI), neurologic complications, and ICU/hospital length of stay (LOS). Comparative analyses were performed between patients having ECMO- and ventricular assist devises (VAD) using Fisher's exact and Wilcoxon rank-sum tests. Kaplan-Meier survival estimates were generated. Results: Thirty patients were transplanted (median age 9 years, 63.3% female). Most (96.7%) needed MCS, including 11 ECMO and 18 VAD. Thirty-day survival was 28/30 (93.5%, 95% CI 78-99). Acute rejection occurred in 3 (10%), infections in 4 (13.3%), AKI in 8 (26.7%), with two requiring CRRT, and neurologic complications in 3 (10.3%). Median ICU and hospital LOS were 20 and 37 days, respectively. ECMO patients had longer post-transplant ventilation (12 vs 6 days, p = 0.04) and ICU length of stay (LOS) compared to VAD patients. Total Ischemic time, and CPB times were associated with increased morbidity. Conclusions: Early outcomes after pediatric heart transplantation prove high short-term survival but substantial morbidity. ECMO bridging was associated with greater resource use than VAD. Improving donor heart ischemic time, donor-recipient matching, perioperative management, and early initiation of durable MCS may further improve outcomes.