5698Parvovirus B19 in endomyocardial biopsy of patients with idiopathic dilated cardiomyopathy: foe or bystander?

Background: Cardiotropic viruses have been suggested as a potential cause of idiopathic dilated cardiomyopathy (IDCM). Although positive serological findings confirming this hypothesis are seldom found in IDCM patients, several studies have proposed that detection of viral genome within the myocardium would support a pathogenic connection with viral disease. Parvovirus B19 (PVB19) has emerged as one of the cardiotropic viruses possibly inducing chronic myocarditis and subsequent IDCM. Objectives: The first aim of this prospective study was to investigate the presence of PVB19 within myocardial biopsies in patients with IDCM and to compare the findings with those of donor hearts (control group); second, we investigated the effect of PVB19 on long-term survival of IDCM patients, and heart recipients, respectively. Patients and methods: Forty patients, 13 women (mean age 50±13y) and 27 men (mean age 46±11y), with mean ejection fraction 27±12%, hospitalised with heart failure of unknown cause, were subjected to a routine diagnostic work-up. After excluding other possible etiologies, IDCM was confirmed, and all patients were investigated with invasive haemodynamics and right ventricular biopsies. The presence of PVB19 DNA in myocardial biopsies, and IgG and IgM antibodies were analysed in patient sera. Heart biopsies from n=20 donor hearts were investigated, as well, and the survival of the recipients was registered.