Pathogenesis of atrial myocarditis in monkeys inoculated with Cb1oxsackie virus B3

Abstract

Coxsackie virus of group B type 3 (CB3) was inoculated into monkeys to determine whether or not atrial myocarditis occur in the heart. The histopathological changes in the atria were moderate to mild degeneration, necrosis, vacuolation of the muscle fibres and inflammatory mononuclear cell infiltration on the degenerating or nerocitizing muscle fibres and in the interstitial tissues. Pericardial lesions in the atria were observed moderate to mild degeneration, oedema, thickness and inflammatory mononuclear cell infiltration. Mild degeneration, inflammatory mononuclear cell infiltration, oedema and thickness were also found in the endocardium. A virus titre was found in the atrial myocardium and virus antigen was detected in degenerating or necrotizing muscle fibres in the auricle by immunofluorescent technique. Serum neutralizing antibody titre had risen in monkeys inoculated with CB3. From the present results, it is clear that CB3 could produce atrial myocarditis as well as ventricular myocarditis. We suggests, therefore, that damage of the atrial myocardium is due to direct action of the virus.