Mortality Predictors in Short-Term Mechanical Circulatory Support as a Bridge to Heart Transplantation

Background/Objectives: This study evaluates the outcomes of extracorporeal membrane oxygenation (ECMO), in venoarterial configuration, and short-term ventricular assist devices (VADs) used as a bridge to heart transplantation (HT). The primary objective was to identify predictors of in-hospital mortality among patients on the urgent HT waiting list receiving short-term mechanical circulatory support, including direct ECMO-to-HT, direct short-term VAD-to-HT, and ECMO as a bridge to short-term VAD followed by HT (ECMO bridge-to-bridge). Secondary objectives included identifying predictors of in-hospital mortality in transplanted patients and assessing their long-term survival. Methods: A single-center, retrospective, observational, and analytical study conducted at a tertiary care hospital, including patients supported with ECMO and short-term VAD support as a bridge to HT between 2007 and 2024. Results: A total of 183 patients were included: 110 in the ECMO-to-HT group, 51 in the VAD-to-HT group, and 22 in the ECMO bridge-to-bridge group. Among them, 147 underwent HT (80.3%). Overall in-hospital mortality was 37.2% (115 of 183 patients survived), while in-hospital mortality among transplanted patients was 21.8% (115 of 147 survived). Independent predictors of in-hospital mortality included infection, ECMO bridge-to-bridge strategy, higher body mass index (BMI), older age, and neurological complications. In the transplanted subgroup, predictors of both in-hospital and long-term mortality were ECMO support and older recipient age. Notably, a donor BMI exceeding that of the recipient by more than 10% was associated with improved survival. Conclusions: The complexity of patients requiring mechanical circulatory support and the physiological effects of different devices necessitate early, individualized management based on the etiology of cardiogenic shock and urgency status.