Waitlist and Posttransplant Outcomes of Children and Young Adults With Hypertrophic Cardiomyopathy

Background: Heart transplantation (HT) is standard therapy for end-stage hypertrophic cardiomyopathy (HCM); however, few studies have described outcomes of older children and young adults with HCM listed for HT. Our objective was to compare waitlist and post–HT outcomes among pediatric and young adult patients with HCM and dilated cardiomyopathy (DCM). Methods: The Scientific Registry of Transplant Recipients was queried for patients with HCM and DCM listed at ≤25 years of age. Patient characteristics, waitlist and post–HT survival were compared between younger (≤5 years of age) and older (>5 to ≤25 years of age) HCM patients and between HCM and DCM patients. Results: Among 6252 patients listed for HT at ≤25 years of age with DCM and HCM, 3926 and 250 were in the older cohort and 1944 and 132 were in the younger cohort, respectively. Older HCM patients were less likely to be critically ill at listing compared with younger HCM patients (P = .0001). Waitlist mortality was similar between HCM and DCM patients in both age cohorts. Post-HT survival in HCM patients was similar between the age cohorts. In the younger cohort, early post-HT survival was worse in HCM compared with DCM (P = .009), with no difference in long-term survival. Survival was similar between the older cohorts. Conclusions: Older children and young adults with HCM are less critically ill than the younger cohort and show waitlist and post-HT survival similar to DCM patients. The young children with HCM had worse early posttransplantation survival, though long-term survival was same as DCM.