Viruses and heart disease: a problem in pathogenesis.

Identification of viral myocarditis offers problems; pathologists fail to agree on the definition of the disease and biopsy-proven cases documented in the English literature are still few in number. Though endomyocardial biopsy is becoming a standard procedure at many medical centers, tissue sampling, especially in cases of patchy myocarditis, can result in further diagnostic difficulties. While conventional wisdom holds dilated cardiomyopathy the end-stage of chronic viral myocarditis, a history of preceding viral infection is usually unobtainable. Some research suggests that myocardial necrosis is a cell-mediated immune process and chronic myocarditis an autoimmune disease. Understanding the true relationship between viruses and heart disease will require further research.