REJECTION OF CARDIAC TRANSPLANT

This report deals with the primary problem in cardiac transplantation, homograft rejection, in its acute and chronic forms. Experience is drawn from 125 orthotopic cardiac transplants in dogs and from 4 human cases. The electrocardiogram is the most reliable indicator of an impending rejection crisis; elevation of lactic dehydrogenase (LDH) isozymes may add confirmation. Treatment of the rejection crisis requires transiently high doses of prednisone in addition to maintenance doses of azathioprine. Experimental data suggest the additional value of graft irradiation. The acute pathologic process is characterized early by infiltration with mononuclear cells. These cells are associated with injury to vascular endothelium which results in interstitial hemorrhage and edema and anoxic injury to the muscle fibers. The chronic form of rejection is manifested by coronary arterial narrowing due to intimai proliferation or thrombus formation, which results presumably from immunologic damage to the endothelium. © 1969.