Virus infection and dilated cardiomyopathy.

The implication of virus infection in the pathogenesis of dilated cardiomyopathy has been strengthened by a number of studies demonstrating a progression from myocarditis to this condition. In this context a histological diagnosis from endomyocardial biopsy is mandatory. Serological studies have provided only circumstantial evidence. The development and clinical application of enterovirus group-specific hybridization probes and the polymerase chain reaction has allowed the detection of enteroviral RNA sequences in endomyocardial biopsy samples from patients in all stages of the disease. The persistence of enteroviral RNA within the myocardium of patients with dilated cardiomyopathy appears to indicate an adverse prognosis for the patient. Preliminary data, however, suggest that disappearance of the virus may be associated with clinical improvement, offering the hope that future antiviral agents may alter the natural history of the disease.