Heart block and leukemic cell infiltration of interventricular septum of heart

A case report is presented, including post-mortem findings, of a patient with acute myeloid leukemia and heart block. There was no narrowing or occlusion of the coronary arteries. Histologic examination of sections of interventricular septum of the heart revealed leukemic cell infiltration, focal atrophy and fibrosis of myocardium. The remainder of the myocardium was not involved in this process. The leukemic cell infiltration of the interventricular septum of the heart was probably the primary etiologic factor in the disturbance of the conduction mechanism. It is suggested that perhaps routine electrocardiograms would reveal more instances of heart block in patients with leukemia since heart block in patients who are anemic and/or febrile may be over-looked on physical examination.