Long-term adult congenital heart disease survival after heart transplantation: A restricted mean survival time analysis

Abstract

Adult Congenital Heart Disease (ACHD) heart transplant recipients may have lower post-transplant survival resulting from higher peri-operative mortality than non-ACHD patients. However, the late risk of mortality appears lower in ACHD recipients. This study seeks to establish whether long-term heart transplant survival is reduced among ACHD recipients relative to non-ACHD recipients. Adult patients who received a heart transplant between January, 2000 and December, 2019 in the United Network for Organ Sharing database were stratified by the presence of ACHD. Propensity-matched cohorts (1:4) were created to adjust for differences between groups. Graft survival at time points from 1 to 18 years was compared between groups using restricted mean survival time (RMST) analysis. The matched cohort included 1,139 ACHD and 4,293 non-ACHD patients. Median age was 35 years and 61% were male. Average survival time at 1 year was 0.85 years for ACHD patients and 0.93 years for non-ACHD patients (average difference: -0.08 years, 95% Confidence Interval [CI] -0.10 to -0.06, p < 0.001), reflecting higher immediate post-transplant mortality. Average survival time at 18 years was not clinically or statistically different: 11.14 years for ACHD patients and 11.40 years for non-ACHD patients (average difference: -0.26 years, 95% CI: -0.85 to + 0.32 years, p = 0.38). Despite increased medium-term mortality among ACHD patients after heart transplant, differences in long-term survival are minimal. Allocation of hearts to ACHD patients results in acceptable utility of donor hearts.