[Coronary lesions of a cardiac transplant. (Chronic cardiac rejection). Study of 15 retransplantations].

In order to precise the pathologic aspects of coronary lesions observed in the accelerated coronary disease after heart transplantation, 15 cases of explanted hearts have been studied, and compared to the findings of previous coronarography. Histopathological aspects, modes of diffusion involving the three main coronaries and distal branches, thrombotic complications and their ischemic consequences showed that coronary lesions result in a few months or years to diffuse circumferential atheromatous like lesions. Localized lesions are less frequently encountered than in common atheromatous coronary disease, but multifocal thrombosis is frequent, found in 40% of the cases. This feature leads to ischemic cardiopathy expressed by cardiac failure, indolent because of the denervation of the heart. Correlations with coronarographies showed that this method underestimated the importance of coronary lesions, for which retransplantation represents the only hope. Risk factors include vascular immunological inflammation, viral infection enhanced by immunosuppression, increased platelet aggregation but we still ignore the respective importance of these factors at the present time.