Gap between availability and utilization of cardiac donors: analysis of determining factors in Ecuador.

Objectives: To analyse factors associated with the rejection of heart donor offers referred to Clínica Guayaquil and to compare these findings with national data from the Instituto Nacional de Donación y Trasplante de Órganos, Tejidos y Células, in order to identify trends influencing organ acceptance. Materials and Methods: We conducted an observational, retrospective study of heart donor offers received between September 2021 and July 2025. Demographic, clinical, anthropometric, and logistical variables were extracted from the institutional database and the National Information System for Donation and Transplantation (SINIDOT). Reasons for organ rejection were classified into eight predefined categories. Univariate and multivariate analyses were performed to identify factors associated with donor acceptance or rejection. Results: A total of 196 heart donor offers were received, of which 75% were rejected. Accepted donor organs were from younger donors, were more frequently male, and had higher predicted heart mass (PHM). Traumatic brain injury was the leading cause of death (49.5%). The most common reasons for rejection were classification as a non-standard risk donor (39.5%), logistical constraints (30.6%), and blood group incompatibility (15.6%). In multivariate analyses, older donor age and origin outside Guayaquil were associated with higher rejection rates, whereas male sex and higher PHM were associated with increased acceptance. Logistical problems rose from 0% in 2021 to more than 40% in 2024-2025, largely driven by limited availability of air transport. Conclusions: The high rate of donor heart rejection reflects substantial underutilisation of potentially viable organs. Strengthening transport logistics and broadening donor acceptance criteria could increase graft utilisation, reduce waiting-list mortality, and improve the overall efficiency of national heart transplantation programmes.