Immunologic events and long-term survival after combined heart and kidney transplantation: A 12-year single-center experience

Background: In this study we compare the incidence of cardiac rejection and long-term survival after combined heart and kidney transplantation (HK) an d single heart transplantation (H). Combined HK transplantation is a surgic al option for patients with irreversible cardiac and renal failure. However , long-term results of combined HK transplantation on immunologic events an d patient survival remain unknown. Methods: Between 1988 and 1997, 12 consecutive patients underwent combined HK transplantation (HK group) at a single institution. A control group (H g roup) of 24 single heart transplant recipients operated on within the same period was matched for age, pre-operative pulmonary vascular resistance, he patic insufficiency and gender mismatch. Recipients and donors were ABO com patible without HLA antigen matching. All patients received immediate tripl e immunosuppression that included cyclosporine. Because of early renal dysf unction, cyclosporine was switched to antithymocyte globulin in 5 patients from the HK group and in 1 patient from the H group (P = 0.01). Results: Actuarial freedom from heart rejection at 6 months and at 1 year f ollowing transplantation averaged 90 +/- 9% and 70 +/- 14% in the HK group, and 65 +/- 10% and 49 +/- 11% in the H group, respectively (p = 0.023). Ac tuarial survival at 1, 5 and 12 years was not significantly different betwe en groups, at 66%, 55% and 28% in the HK group, and 66%, 44% and 32% in the H group, respectively (p = 0.66). Conclusion: The incidence of cardiac rejection was significantly lower. Lon g-term survival in the HK group was similar to that in the H group. Putativ e mechanisms of decreased cardiac rejection in the HK group include allogen eic stimulation, donor-derived dendritic cells and induction by anti-thymoc yte globulins. The need for longterm immunosuppression may be reduced after combined heart and kidney transplantation.