Cardiac involvement in Whipple's disease.

Although cardiac involvement in Whipple's disease has been reported previously, the extent and significance of such involvement has not been stressed. In our series of 19 patients, 58% had clinical cardiac findings and 79% had gross cardiac lesions at autopsy. Histologically there were PAS-positive macrophages in the pericardium, myocardium, and valves of each of these patients. These collections of macrophages were associated with chronic inflammatory cells and foci of fibrosis with resultant adhesive pericarditis, focal myocardial fibrosis similar to the fibrosis of idiopathic cardiomyopathy, and valvular fibrosis with deformity grossly resembling the valvular lesions of chronic rheumatic heart disease. Four of the patients with mitral valvular deformity had cardiac murmurs, and ECG changes were noted in six patients with mitral myocardial fibrosis. In addition, pericardial friction rubs were heard in two patients. By electron microscopy rod-shaped bodies, presumably bacteria, were noted in the mitral valve and myocardium. The structures are identical to those described in the small intestinal mucosa of patients with Whipple's disease and presumably are the causative agent of the pancardiopathy.