Diabetic cardiomyopathy. A morphological study of intramyocardial arteries.

The mechanism of heart failure in patients with diabetic cardiomyopathy is not clear. Previous studies suggested that vascular lesions specific for diabetes mellitus were present and that the lesions could be the basis for impaired cardiac function. We have investigated the histologic and histochemical characteristics of intramyocardial vessels (20 to 500 microns) in a group of diabetics using comparable groups of patients with hypertension, patients with hypertension and diabetes mellitus, and, as controls, patients with neither hypertension nor diabetes mellitus. Analysis of multiple blocks taken from the 42 study patients disclosed no lesions specific for diabetes mellitus or hypertension. The discrepancy between our findings and earlier reports is probably due to a lack of controls and the use of non-perfusion-fixed material in the earlier studies.