Survival After Cardiac Transplantation in Adults With Single-Ventricle Congenital Heart Disease.

Background: Without large-scale analyses of adults with single-ventricle congenital heart disease (CHD) undergoing heart transplantation, little evidence exists to guide listing practices and patient counseling.

Objectives: This study aims to evaluate survival after heart transplantation in adults with single and biventricular CHD and compare it to that of non-CHD transplant recipients.

Methods: In this 15-year (2005-2020) retrospective analysis, outcome-blinded investigators used probability-linkage to merge the National (Nationwide) Inpatient Sample and Organ Procurement and Transplantation Network data sets.

Results: Of 382 adult (≥18 years of age) heart transplant recipients with CHD, 185 (48%) had single-ventricle physiology. Compared to biventricular CHD, single-ventricle patients showed significantly reduced survival at 1 (80% vs 91%; HR: 2.50; 95% CI: 1.40-4.49; P = 0.002) and 10 years (54% vs 71%; HR: 2.10; 95% CI: 1.38-3.18; P < 0.001). Among patients who survived the first post-transplantation year, biventricular CHD patients exhibited similar 10-year survival as single-ventricle patients, except for those with hypoplastic left heart syndrome (79% vs 71%; HR: 1.58; 95% CI: 0.85-2.92; P = 0.15). Additionally, biventricular CHD transplant recipients showed significantly better 10-year conditional survival compared to their non-CHD counterparts (79% vs 68%; HR: 0.73; 95% CI: 0.59-0.90; P = 0.003).

Conclusions: Among adult CHD transplant recipients, single-ventricle physiology correlated with higher short-term mortality. However, 10-year conditional survival was similar for biventricular and most single-ventricle CHD patients, and notably better for biventricular CHD patients compared to non-CHD heart transplant recipients. These findings have significant implications towards patient selection and listing strategies, easing concerns related to heart transplantation in adults with CHD and destigmatizing most subtypes of single-ventricle CHD.