Current challenges in pediatric heart transplantation for congenital heart disease

Pediatric heart transplantation is an established therapy for end-stage cardiac disease without suitable medical or surgical options. However, transplantation for congenital heart disease carries an incremental risk that challenges the pediatric transplant team on multiple levels.

With improved outcomes following palliative and corrective congenital cardiac surgery, cardiac transplantation has decreased in recent years as a primary therapy. Nevertheless, congenital heart disease remains the most common indication for cardiac transplantation during infancy. Primary transplantation in infancy is selectively recommended for severe systemic ventricular dysfunction, severe atrioventricular valve insufficiency, and occlusive coronary artery anomalies, particularly with single ventricle physiology. Wait-list mortality remains highest for infants with prior palliative surgery and patients with failing Fontan physiology, both of whom have limited options for effective mechanical circulatory support. The sensitized patient carries an increased risk with prolonged wait times, although virtual cross-matches and single bead assays for donor-specific antigens have facilitated the transplant process. Early and late survival after transplantation for congenital heart disease remain inferior to cardiomyopathy, with prior Fontan procedure as a major risk factor. However, among survivors at 6 months, late outcomes are generally excellent. Major late causes of death include allograft vasculopathy, post-transplant lymphoproliferative disease, and acute rejection. Noncompliance with medications remains a major risk for teenage mortality.

Despite the myriad of evolving challenges, pediatric heart transplantation for congenital heart disease enjoys routine short and long-term success at experienced centers for the vast majority of such patients without other options.