Detection of enteroviral infection in myocardial tissues by polymerase chain reaction (PCR).

OBJECTIVE: To determine if enteroviral infection is linked to myocarditis and dilated cardiomyopathy. Enteroviruses, especially coxsackieviruses, appear to be the most common agents of viral myocarditis. METHODS: We collected 53 endomyocardial biopsies and two autopsy specimens from 41 patients affected by myocarditis or dilated cardiomyopathy. The patients were diagnosed clinically, hemodynamically, virologically and histologically (Dallas classification). We tested for the presence of enteroviral sequences by PCR, using 5prime prime or minute non-coding (coxsackievirus B3, CB3, map position 450--474, 584--603) derived primers. Specificity was confirmed using the Southern blot. We used a fraction of CB3 acutely infected mouse myocardial tissue as a control. RESULTS: We detected enteroviral sequences in four patients with active myocarditis, borderline myocarditis or cardiomyopathy. The patient with active myocarditis had shown neutralizing antibodies in serologic analysis for coxsackievirus B3 and B5. CONCLUSIONS: The data support a weak link of enteroviral infection to human myocarditis and dilated cardiomyopathy, at least when using a PCR assay on biopsies.