Comparison of Heart Transplantation Outcomes - Adult Congenital Heart Disease Versus Matched Cardiac Patients in a Quaternary Reference Centre.

BACKGROUND: The number of transplants performed for adult congenital heart disease (ACHD) patients is increasing. We sought to compare survival and post-transplant complications, including graft failure, rejection, dialysis and use of RVAD postoperatively, between ACHD and a cohort of dilated (DCM) and ischemic (ICM) cardiomyopathy patients matched in age and year of transplantation. METHODS: We retrospectively reviewed our single-institution heart transplant database and selected all patients who had surgery between 1988 and 2017. In our primary analysis, we looked at survival and post-transplant complications across cardiomyopathy groups. Our secondary analysis was matched in order 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. By multivariable analysis, ICM and DCM patients showed a 66% relative reduction in risk of death compared to the ACHD group. The matched analysis showed no significant difference in survival across groups. CONCLUSION: ACHD patients represent a growing high-risk patient cohort referred for transplantation. To improve survival outcomes we need to address modifiable risk factors.