LAUSR

Purpose There are limited data reporting outcomes of children with trisomy 21 undergoing heart transplantation (HTx). This project reports the waitlist and post-HTx outcomes of children with trisomy 21. Methods This is a retrospective cohort study of children with trisomy 21 listed for or who underwent HTx at 11 centers within North America and internationally. Demographic, medical, surgical, and post-HTx outcome data were collected and described. Results Twenty-one patients with trisomy 21 were listed for HTx from 1992 through 2019 (median age 8.5y, 43% male, 52% white). High-risk or failed repair of congenital heart disease was the indication for transplant in 16 (76%) patients with atrioventricular septal defect being the most common (N=12). Other diagnoses included dilated cardiomyopathy in 4 patients (secondary to anthracyclines in 2) and myocarditis in 1 patient. A total of 18 (86%) patients survived to transplant. Of this group, support at the time of transplant included inotropes (N=10, 56%), ventricular assist device (N=7, 39%), and mechanical ventilation (N=2, 11%). No patients required post-operative extracorporeal membrane oxygenation or dialysis. All centers reported the use of standard immunosuppression without alterations secondary to trisomy 21. All transplanted patients survived to hospital discharge with a median post-HTx length of stay of 19d. With a median follow-up of 2.9y, 16 (89%) patients were alive, 5 (28%) had rejection within the 1st year post-HTx, 2 (11%) developed post-transplant lymphoproliferative disorder (PTLD), and 7 (39%) were hospitalized for infection within the 1st year post-HTx. For the two post-HTx mortalities, the causes of death were 1) coronary allograft vasculopathy at 22y post-HTx and 2) multiple episodes of rejection and PTLD at 1.5y post-HTx (Figure). Conclusion Waitlist and intermediate post-HTx outcomes are acceptable in children with trisomy 21. The presence of trisomy 21 should not be an absolute contraindication to heart transplantation in the appropriate clinical setting.