An 82-year-old woman was admitted with severe chest pain and orthopnea on January 17, 1997. Physical examination revealed bilateral leg edema and cyanosis at the periphery of the extremities. The serum CK level was 488 IU/l on admission and increased to a maximum value of 4,866 IU/l 8 hours after admission. An echocardiogram demonstrated diffuse severe hypokinesis in the left ventricle. Serial electrocardiograms showed transient right bundle branch block, left bundle branch block, and normal sinus rhythm. The patient was diagnosed as having congestive heart failure. Artificial ventilation was performed, and furosemide, isosorbide dinitrate and dopamine were administered. A right ventricular endomyocardial biopsy performed on the 13th hospital day demonstrated moderate hypertrophy and disparity of cardiac myocytes and fibrosis around the myocytes, and few inflammatory cells in the specimens. This biopsy finding was not compatible with acute myocarditis but with the chronic stage of myocarditis. The patient was discharged on the 45th hospital day, but returned because of a recurrence of congestive heart failure. After an improvement of the heart failure, a coronary angiography was performed on the 20th hospital day. The coronary angiography revealed significant stenosis in three vessels. This elderly patient had congestive heart failure and triple-vessel coronary artery disease with transient alternating bundle branch blocks on serial electrocardiograms. Alternating bundle branch blocks and diffuse left ventricular dysfunction was considered to be induced by the aging process, postmyocarditic change of myocytes, and triple-vessel coronary artery disease in this case.