Accelerated atherosclerosis of cardiac grafts is one of the factors limiting long-term survival after cardiac transplantation. The authors report the case of a patient who had a cardiac arrest associated with severe atherosclerosis 18 months after transplantation. The severity of the coronary lesions was underestimated by coronary angiography. An ergometrine test induced coronary spasm, a phenomenon which has only rarely been observed in transplanted hearts. The patient died one month later despite calcium inhibitor therapy. Autopsy revealed very severe triple vessel disease. This case illustrates the possible rapid evolution of coronary artery disease in cardiac transplant recipients, the difficulty in evaluating the severity of the lesions by coronary angiography and the additional possibility of observing coronary spasm in these cases.