Powerful but limited immunosuppression for cardiac transplantation with cyclosporins and low-dose steroid.

Cyclosporin and low-dose prednisone provide powerful but limited immunosuppression for orthotopic cardiac transplantation. Optimal long-term survival was possible only with rescue therapy using rabbit antithymocyte globulin (RATG) when myocyte necrosis could not be reversed with pulse steroid therapy. The continued absence of rejection following rescue therapy with RATG in six of the last 19 patients is responsible for the improved 79% cumulative survival rate at 9 months compared to the 61% cumulative survival rate at 1 year for the initial 23 patients. The difference is that among the latter group, seven patients had persistent histologic rejection with focal myocyte necrosis which was not reversed with pulse therapy of steroids (hydrocortisone) or an increased dose of maintenance prednisone (30 to 40 mg/day). Three of these seven died of acute rejection within 3 months and four died between 8 and 13 months. Consequently, the cumulative survival rate of these 23 patients at 2 years was 41%. The projected 2 year cumulative survival rate of the 19 patients should not decrease greatly, as new episodes of rejection have not occurred beyond 3 months in either group.