Enteroviruses and idiopathic dilated cardiomyopathy.

Previous studies have suggested that some cases of idiopathic dilated cardiomyopathy (IDC) are due to persistent viral infection following an episode of viral myocarditis. Viral RNA sequences have recently been detected in material from patients with IDC using molecular biological techniques. We tested 40 samples from recipients' hearts explanted at cardiac transplantation for the presence of enteroviral RNA sequences, using a Northern blotting technique. Material from 19 cases of IDC and 21 cases of non-cardiomyopathic cardiac failure was examined together with Coxsackie-virus-infected neonatal mouse heart as a positive control and non-infected adult mouse heart as a negative control. A sharp band of viral RNA was detected in the positive control sample. No hybridization signal attributable to viral RNA was obtained for the negative control or for any of the test samples. We conclude that the role of enteroviruses in the pathogenesis of cardiomyopathy is not fully established and that further study is warranted.