Partial heart transplant provides a safe and effective valve replacement alterative with the capacity for valve growth in children with congenital heart disease, decreasing the need for reoperation, according to a small retrospective study published Aug. 27 in JAMA.

Douglas M. Overbey, MD, MPH, et al., looked at a pediatric cohort of 19 children (median age, 97 days at time of transplant; 47% female) with congenital heart valve disease who received a partial heart transplant to replace the aortic and/or pulmonary valve at a single U.S. center. The approach involved implanting freshly procured donor tissue and maintaining viability with immunosuppression.

Types of partial heart transplants included both semilunar valves in three patients and living pulmonary valve replacement in the pulmonary position in seven patients. Additionally, two patients had a living aortic valve allograft in the aortic position and seven were in the pulmonary position.

Results showed a median operative time of 294 minutes; cardiopulmonary bypass time was 145 minutes. Intensive care and hospital lengths of stay were a median of nine and 13.5 days, respectively.

Annular diameter and valve leaflet length were longitudinally analyzed for growth in nine patients. Notably, at a median of 26.4 weeks, findings revealed excellent valve function and appropriate vessel and valve leaflet growth.

Specifically, annular diameter increased from medians of 7 mm (aortic valve) and 9 mm (pulmonary valve) to 14 mm and 17 mm, respectively. Similarly, leaflet length increased from medians of 0.5 mm (aortic valve) and 0.49 mm (pulmonary valve) to 1 mm and 0.675 mm, respectively.

For maintenance immunosuppression, patients received tacrolimus monotherapy with a trough level goal of 4 to 8 ng/mL and mycophenolate mofetil. No significant immunosuppression complications were reported.

In an accompanying editorial comment, Kevin P. Daly, MD, writes that partial heart transplant in this patient population "has opened a new pathway to utilize viable valves to better meet the needs of growing children." Daly emphasizes that "collaboration regarding allocation, regulation, and appropriate immunosuppression strategies is urgently needed to optimize this innovative therapy."