[Viruses and atherosclerosis]

Our understanding of the pathogenesis and aetiology of atherosclerosis remains incomplete. An infection by herpesviruses is among the plausible hypotheses. In chicken, inoculation with Marek's disease virus provokes arterial lesions closely resembling atherosclerotic plaques. Experiments done on cultured arterial cells have shown that herpesviruses might enhance atherogenesis. Herpesviruses molecules (proteins, messenger ribonucleic acid, deoxyribonucleic acid) are commonly found in the human arterial wall. According to a recent study using gene amplification by the polymerase chain reaction, the complete cytomegalovirus genome can be detected in 90 p. 100 of the samples from atherosclerotic plaques and in 53 p. 100 of the samples from normal arterial wall. Cytomegalovirus infection appears to increase the risk and severity of atherosclerotic lesions which develop in heart grafts and compromise their survival. These data are not sufficient to prove that herpesviruses, especially cytomegalovirus, play a causal role in human atherosclerosis. The viral hypothesis, however, must be considered as serious and is certainly worth further investigations.