Fatal infection withBorrelia burgdorferiby involvement of the cardiac conducting system

Abstract

The cardiac conducting system of a patient with fatal cardiac involvement byB. burgdorferi showed necrosis of associated muscle fibers in the sinoatrial node with lymphoplasmacytic infiltrate and focal edema. Lymphocytic infiltrate was also found around the atrioventricular node and in the penetrating bundle and branching bundle. Fibrosis in the left bundle branch apparently resulted in nearly complete discontinuation of the fibers. Peripheral neural and muscular tissue also showed signs of inflammation. Spirochetes were demonstrated in the branching bundle and between the muscular fibers of the right atrium. Peripheral neural and muscular tissue showed signs of disseminated Lyme borreliosis.