Heart and lung transplantation: autotransplantation and allotransplantation in primates with extended survival

Abstract

Combined heart and lung transplantation was performed in rhesus or cynomolgus monkeys in order to confirm the ability of primates to withstand complete cardiopulmonary denervation, to develop a satisfactory operative method, and to obtain survival of allotransplant recipients using Cyclosporin-A immune suppression. Twenty-seven monkeys weighing 2.6 to 10.1 kg received either autotransplants or allotransplants by two different operative techniques. Seventeen animals were operated upon with hypothermia and circulatory arrest. One autotransplant recipient is alive at 368 days, but all allotransplant recipients (untreated) died within 5 days despite normal breathing patterns. Ten animals operated upon with the aid of cardiopulmonary bypass fared better. Three autotransplant recipients are alive 60, 199, and 312 days postoperatively. Three of seven allotransplant recipients treated with Cyclosporin-A (25 mg/kg, then tapered) and azathioprine (2 mg/kg for 14 days) were long-term survivors. One died at 144 days of lymphoma and two are currently living 156 and 191 days postoperatively. The results suggest that heart and lung transplantation is possible in primates and that allografted recipients can survive for extended periods with Cyclosporin-A used for immune suppression.