ABSTRACT
The impact of type 2 diabetes and obesity on left ventricular size and function is not well established and still a matter of debate. The study was performed to assess LV size and function in type 2 diabetic patients obese or not. The study included 40 normotensive patients with type 2 diabetes, 20 of them were obese [group I], and the other 20 patients were lean [group II]. The control of the study included 40 healthy subjects with age and sex matched, 20 of them were obese [group III], and the other 20 subjects were lean [group IV]. The study was performed at Al-Azhar University hospitals from October 2005 to July 2006. Patients and controls were subjected to clinical evaluation, with special emphasis to measurements of body mass index [BMI], waist hip circumference ratio [WHR], ECG and standard 2-D echocardiograms. Laboratory investigations include; lipid profile, HbA1c, fasting blood sugar [FBS], fasting serum insulin and measurements of insulin resistance [IR]. LV functions [EF, FS% and E/A ratio] were significantly impaired in-group I and II when compared to controls [p<0.05] and more significantly impaired in-group I when compared to group II [p<0.05]. Left ventricular mass was significantly higher in obese groups [group I and III] when compared to lean groups [group II and IV], [p<0.01], and no significant changes were found between obese diabetic and non-diabetics. All values of LV mass, EF and FS% are still within the normal reference range and all patients had no ECG abnormalities. Hyperinsulinemia and insulin resistance were significantly higher in diabetic groups when compared to controls [p<0.01] and in-group I when compared to group II [p<0.01]. Total cholesterol, LDL-cholesterol, triglycerides, HbA1c, fasting insulin and IR were significantly higher, while HDL-cholesterol was significantly lower in-group I when compared to group II, in-group I when compared to group III, and in-group II when compared to group IV. In obese diabetic patients LV mass was correlated with BMI, waist circumference, serum insulin, and IR. EF and FS% correlated with BMI, waist circumference, triglycerides, HDL-cholesterol, disease duration, HbA1c, serum insulin, and IR. E/A ratio correlated with BMI, waist circumference, HDL-cholesterol, triglycerides, disease duration, HbA1c, serum insulin, and IR. In obese non-diabetic subjects LV mass was correlated with BMI, waist circumference, serum insulin and IR. EF and FS% correlated with BMI, waist circumference, serum insulin, and IR. E/A ratio correlated with BMI, waist circumference, serum insulin, and IR. We can claim that simple obesity has its main impaction on LV size rather than functions, while diabetes has its main impaction on the LV functions. These denoting the other mechanisms of cardiovascular affection in diabetes including endothelial dysfunction and microvascular angiopathy