Comparison of Heart Transplantation Outcomes: Adult Congenital Heart Disease vs Matched Cardiac Patients in a Quaternary Reference Centre

Background: The number of transplantations performed for adult congenital heart disease (ACHD) patients is increasing. We sought to compare survival and post-transplantation complications, including graft failure, rejection, dialysis, and use of a right ventricular assist device, between ACHD and a cohort of dilated (DCM) and ischemic (ICM) cardiomyopathy patients matched by age and year of transplantation. Methods: We retrospectively reviewed our single-institution heart transplantation database and selected all patients who had surgery from 1988 to 2017. In our primary analysis, we looked at survival and post-transplantation complications across cardiomyopathy groups. Our secondary analysis was matched to mitigate era effects as well as differences in age at transplant. Results: We analyzed a cohort consisting of 303 heart transplant patients with cardiomyopathy due to either 1) ACHD (n = 38), 2) ICM (n = 110), or 3) DCM (n = 155). Kaplan-Meier analysis and a multivariable Cox proportional hazard regression model were used for all-cause mortality, and cause-specific hazard regression for cause-specific mortality and morbidity. There was no statistically significant survival difference across groups. The 1-year survival was 68.5% for ACHD, 85.4% for ICM, and 85.5% for DCM. In multivariable analysis, ICM and DCM patients showed a 66% lower risk of death relative to the ACHD group. The matched analysis showed no significant difference in survival across groups. Conclusions: ACHD patients represent a growing high-risk patient cohort referred for transplantation. To improve survival outcomes we need to address modifiable risk factors.