Cardiac Transplantation in Danon Disease.

BACKGROUND Danon disease (DD) is a rare X-linked dominant cardioskeletal myopathy caused by mutations in the lysosome-associated membrane protein-2 (LAMP-2) gene that is usually lethal without cardiac transplantation. The purpose of this study is to characterize post-transplant outcomes in a large cohort of DD patients who underwent cardiac transplantation. METHODS Clinical phenotype and outcome data of patients with DD who underwent cardiac transplantation (N=38, 19 males and 19 females) were obtained from 8 centers. Study outcomes included graft survival defined as death or re-transplantation, and episodes of acute cellular and antibody mediated rejection and cardiac allograft vasculopathy at 1 year. RESULTS Median follow-up time after transplantation for the entire cohort was 4.4 years (IQR: 1.5 - 12.8 years). The median age at transplant for the cohort was 20.2 years (15.8 - 27.9 years), with no difference in age between sexes. Median pre-transplant left-ventricular ejection fraction for the entire cohort was 30% (Range 11%-84%). Males had higher pre-transplant AST, ALT, and CPK levels, compared to females (p<0.001). There were 2 deaths in the entire cohort, and 2 re-transplants. There was no difference in actuarial graft survival between males and females (p=0.8965), with an estimated graft survival of 87.1% (95%CI: 63.6-95.9%) at 5 years. One episode (2.7%) of AMR grade 2 and 7 episodes (19%) of ACR grade 2 or 3 were reported in patients who survived to discharge (6 females and one male, p=0.172). CONCLUSIONS Heart transplantation outcomes are acceptable in DD with high probabilities of 5-year graft survival for males and females suggesting that cardiac transplantation is an effective treatment option for DD patients.