Partial heart transplant safe, feasible in congenital heart disease

A partial heart transplant appears to be a safe and efficacious approach to replace a faulty heart valve in children with congenital heart disease, as shown in a study.

Researchers conducted a case series of the first 19 patients (median age at transplantation 97 days, 53 percent male) to undergo partial heart transplantation at a single high-volume paediatric cardiac surgery and transplant centre in the US. For maintenance immunosuppression, tacrolimus monotherapy was administered, with a trough level goal of 4–8 ng/mL.

Growth of the transplanted valve annulus and leaflets over time was assessed as the efficacy outcome. Secondary outcomes included valve dysfunction and complications related to immunosuppression.

The median follow-up was 26 weeks, and none of the patients were lost to follow-up.

Of the patients, three received partial heart transplant of both semilunar valves, seven underwent living pulmonary valve replacement in the pulmonary position, two had a living aortic valve allograft in the aortic position, and seven had a living aortic valve allograft in the pulmonary position.

In a subset of nine patients, the researchers measured the size of the heart valve and its leaflets to see if they grew over time. All valves functioned well and increased in size within appropriate z-scores. Annular diameter increased from a median of 7 to 14 mm for the aortic valve and from 9 to 17 mm for the pulmonary valve. Similarly, leaflet length increased from a median of 0.5 to 1 mm for the aortic valve and from 0.49 to 0.675 mm for the pulmonary valve.

Reoperation was performed in one patient, with the procedure not related to the implanted valve. No significant immunosuppression-associated complications were observed.