HEMODYNAMICS AND CARDIAC CONTRACTILE FUNCTION IN TYPE 1 DIABETES

The cardiohemodynamics was studied 1 week after the administration of streptozotocin (60 mg / kg) or 2 weeks after a dose of 30 mg / kg. All rats had a significantly elevated level of glucose in the blood (up to 27-31 mM). In an echocardiographic study, about 1/3 of diabetic animals exhibited systolic dysfunction, and the remaining 2/3 - diastolic dysfunction with an increase in isovolumic relaxation time by 1.5 times. The catheterization of the left ventricle (LV) with a sensor that allows simultaneous measuring LV pressure and volume in both groups revealed decreased cardiac output by 25-31% and maximal ejection rate by 34-50%. However, LV developed pressure, the maximal rate of its development and the level of blood pressure remained within the control values, thus reduced LV ejection rate was probably due to increased arterial stiffness - a negative correlation was found between these indicators (r = - 0.70). The diastolic dysfunction group differed from systolic dysfunction by a significantly smaller end diastolic volume by 22%. Thus, in type 1 diabetes, LV remodeling with reduced end diastolic volume allows to maintain a normal ejection fraction in the presence of distinct heart failure.