[Cardiomyopathy in diabetes. Ultrastructural examinations]

The functional and morphological changes in myocardium of diabetic patients is caused by diabetic macroangiopathy, diabetic microangiopathy, autonomic neuropathy and metabolic disorders. Mechanism of these changes in the course of diabetes is not fully known. To determine whether there are myocardial ultrastructure differences between patients with diabetic cardiomyopathy (normal coronary angiograms) and diabetic patients with coronary artery disease, electron microscopy examination were performed of 70 sections received from seven biopsied patients (1F, 6M), average age 53 years (range: 42-60) with diabetes type II WHO (group A) without clinical evidence of prior coronary artery disease and hypertension, and 100 sections from 10 patients (2F, 8M), average age 54 years (range: 42-65) with diabetes and coronary atherosclerosis. These patients had clinical evidence of heart failure and were submitted to bypass-graft operations (group B). Endomyocardial biopsy tissues were obtained from the right ventricle without complications either during or after the procedure. Obtained biopsy specimens were fixed in 3% glutaraldehyde stabilized with 1M cacodylate buffer at pH 7.4, postfixed in 1% OsO4 on cacodylate buffer. The materials were then dehydrated and embedded in epon. The Irvin-Fischer test for statistical analysis was used. A p value < 0.05 was considered significant. The presence of focal mild loss of myofibrils (+) was statistically more frequent in the patients in A group (p < 0.05). It was found in 86% (6/7) of cases in A group, while in the B group was observed in 20% of (2/10) cases.(ABSTRACT TRUNCATED AT 250 WORDS)