[A clinicopathologic study of dilated cardiomyopathy in the aged].

Unlabelled: This is a report of a clinicopathologic study of seven cases with dilated cardiomyopathy (DCM) among 3,000 consecutive autopsied cases 60 years or more in age. In this study DCM in the aged was defined as 1) cases of refractory heart failure with marked cardiomegaly of unknown cause by clinical and pathologic examinations, excluding hypertensive heart disease, ischemic heart disease, and valvular heart disease, and 2) pathologic examinations showing cardiac weight more than 400 g, normal coronary arteries with less than 9/15 coronary stenotic index (CSI) and a globular shaped heart with marked dilatation of the left ventricle. The following results were obtained: Seven cases of DCM in the aged consisted of two men and five women with an average age of 69.7 years. The incidence was 0.23% (7/3,000 autopsies). The average age of this group was less than those with other heart diseases such as myocardial infarction or valvular disease in the aged.

Clinical findings: The clinical course ranged from 3 to 22 years with a mean of 12 years. The symptoms of three of the seven cases persisted from the middle age. Electrocardiograms showed atrial fibrillation in five cases (71%), left bundle branch block in three (43%) and complete heart block in one (14%). The mean cardiothoracic ratio was 77.3%. Valvular regurgitation was detected in five cases including five with mitral regurgitation (MR) and three with tricuspid regurgitation (TR). All patients died of cardiac events. Pathologic findings: The heart weights ranged from 410 g to 600 g, with an average of 527 g, and a CSI from 1/15 to 8/15 with a mean of 4.4/15. Though five cases had valvular regurgitation, no primary change was observed in the corresponding valves. Therefore, the valvular regurgitation in these cases were attributed to secondary changes due to dilatation of the valve ring and/or associated decreased compliance of the ventricular wall. The circumferences of the atrioventricular valve rings were enlarged, but the semilunar valve rings were in normal range. Bilateral atrial and ventricular volumes calculated morphologically were larger [201 ml (normal 77 ml) and 83 ml (normal 29 ml), respectively]. Three cases had mural thrombi, two of whom developed pulmonary infarction. Histologically, there were three cases with the fibrosis dominant type, two with the hypertrophy dominant type, one with the degenerative type, and one of the mixed type, respectively.