[The dynamics of cardiac contraction in dogs with alloxan diabetes]

Development of alloxan diabetes was accompanied in dogs by regular changes in the phasic structure of the cardiac contractions. Direction of the changes in the indices of phasic analysis in the groups of dogs with an average (up to 144.3 +/- 12.5 mg%) and marked (up to 258.0 +/- 22.8 mg%) increase in the blood sugar level was the same, but their expression increased with the elevation of hyperglycemia. In marked hyperglycemia there was established an increase (in comparison with normal values) of the index of myocardial tension, a shortening of the period of ejection, a decrease of the mechanical coefficient and of the intrasystolic index, this coinciding with the character of changes of the corresponding indices in the patients suffering from diabetes mellitus, depending on the severity of the disease. The data obtained pointed to the significant influence of metabolic changes (assessed by hyperglycemia level) on the contractile function of the heart.