HEART TRANSPLANTATION IN ADULT WITH CONGENITAL HEART DEFECTS: HOW FAR IS TOO FAR IN WAITING LIST? SIEVING RESULTS THROUGH A RISK SCORE

Background: Adult with congenital heart defects (ACHD) constitute a heterogeneous and expanding group of patients. ACHD are characterized by complex cardiac anatomical features, precarious hemodynamic stability and associated multiorgan dysfunction, with higher risk for advanced heart failure requiring orthotopic heart transplantation (OHT). To stratify this risk, Seese et al. proposed an ACHD-OHT-Risk Score for 1-year mortality including age, comorbidities and laboratory values. This study evaluated early and long-term survival of ACHD underwent OHT in our unit and the adherence of the ACHD-OHT-Risk Score for our population. Methods: ACHD (age>16 years) underwent OHT between January 1997 and August 2024 were analyzed in the study. Kaplan-Meier analysis was performed to report the early and long-term survival. In addition, population was divided in two groups according to the ACHD-OHT-Risk Score: Low-risk (<2 points)-High-risk(≥2points). Groups’ survival at 1year was compared. Results: From 1997 to 2024, 33 ACHD underwent OHT. Mean age at transplant was 33,32 ± 12,60 years. Parameters used to determine the risk score are reported in fig.1. The overall survival at 1, 10,20 years was 84.8%, 77.7% and 64.8% respectively. Low-risk group included 13 patients (39,4%), High-risk group 20 patients (60,6%). One-year survival in low-risk group at 1,6,12 months was 100%,92%,92%, while in high risk group 95%,80% and 80%, respectively (log- rank=0.33). Conclusion: OHT in ACHD remains challenging and affected by high risk mortality in the first year of follow-up. The ACHD-OHT-Risk Score derived some risk factors of early mortality and could suggest a more aggressive approach to waiting list enrolment and progression to achieve OHT in optimal multiorgan conditions.