Non invasive evaluation of left ventricular performance in 294 diabetic patients without clinical heart disease

The authors studied the modification of systolic time intervals (STI), pre-ejection period (PEP) and left ventricular ejection time (LVETc), before and after isometric exercise, in 294 diabetic patients without clinical evidence of cardiomyopathy and in good metabolic control compared to 132 normal subjects. The study was aimed at detecting preclinical alterations of left ventricular function. Diabetic patients considered together did not show any difference in STI in basal conditions or after isometric exercise compared to normal subjects. When diabetic patients were divided into sub-groups according to their treatment, the insulin-treated diabetics showed modification of STI after isometric exercise, which indicated an alteration of left ventricular function. Also subjects treated with oral hypoglycemic agents showed similar but less evident changes. In diabetic patients on diet only and in those with duration of diabetes of 6 months or less, STI was identical to that of normal subjects. These data do not explain the pathogenesis of myocardial involvement, although they are in accordance with studies which have laid emphasis on the alteration of compliance of the diabetic heart.