Cytomegalovirus associated inflammatory heart muscle disease

Cytomegaloviruses(CMV) belong to a group of cardiotropic DNA-viruses with well-documented but sporadic cardiac involvement. By in situ hybridization with a biotinylated cDNA probe CMV-DNA was analysed in 2 different series of patients(1982-1988; 1989-1991) in the endomyocardial biopsy specimens of 35 patients with active myocarditis as defined by the Dallas criteria, and of 35 patients with acute perimyocarditis (pericardial effusion and cardiomegaly or segmental wall motion abnormality and/or an endomyocardial biopsy positive for active myocarditis) were analysed. 51% of patients with active myocarditis, 65% positive findings were observed in patients with perimyocarditis when all positive signals in the myocardium were taken into account. Since in interstitial cells and the vascular endothelium HCMV-DNA was also detected in controls we conclude that only HCMV-DNA in the nuclei are specific for HCMV-associated myocarditis. The incidence of positive signals in the myocytes was lower: 14% of all myocarditis patients and 8.5% of all pericarditis patients demonstrated this pattern. The results from in situ hybridization were compared to circulating anti-CMV antibodies from by an ELISA. As possible predisposing immunologic factors or associated alterations of effector functions we found a shift from normal to reduced natural killer cell activity and a marginal increase in B- and activated T-cells in the peripheral blood.