Impact of adult congenital heart disease on survival and mortality after heart transplantation

Background: Reduced early survival has been reported in adult congenital heart disease (ACHD) heart transplant (HTx) recipients, but little is known about late outcomes after HTx. The aim of this study was to examine survival; causes of death; and predictors of early (<1 year), mid-term (1 to 5 years) and late (>5 years) mortality in ACHD HTx recipients.

Methods: ACHD patients undergoing HTx between 1985 and 2010 were identified in the transplant registry of the International Society for Heart and Lung Transplantation (ISHLT). Survival was compared between ACHD and other adult HTx recipients ("controls") using the Kaplan-Meier method. Factors associated with survival beyond 1 year were assessed using multivariable proportional hazards regression analysis.

Results: Of 85,647 adults who underwent HTx, 1,851 (2.2%) were transplanted for ACHD. Early death secondary due to technical reasons was high among ACHD HTx recipients: 10% vs. 4% in controls (p < 0.0001). However, long-term survival of ACHD recipients who survived the early hazard phase was superior compared with controls (p < 0.0001). This was in part due to a lower infection (p < 0.0001) and malignancy-related (p < 0.01) mortality. Cardiac re-transplantation in ACHD HTx recipients was associated with a 2.75-fold increase in mortality.

Conclusion: A "survival paradox" exists among ACHD recipients, whose high early mortality is balanced by better long-term survival in those who survive the early hazard phase after HTx. A high mortality risk after cardiac re-transplantation in this group of patients suggests that this treatment option should only be considered in carefully selected ACHD HTx recipients.