Changes in systolic time intervals during treatment of diabetes mellitus.

Abstract

The cardiovascular response to the control of diabetes by sulphonylurea drugs has been investigated using systolic time intervals in a group of 19 diabetics. Before treatment a significantly greater heart rate and shortening of QS2 interval and left ventricular ejection time index were encountered among the more hyperglycaemic diabetic patients requiring drug therapy while all diabetics had a reduction of pre-ejection period index. There was a gradual return of resting heart rate and systolic time intervals to control values along with the fall in plasma sugar concentration during treatment. A likely explanation of the findings is that uncontrolled diabetics, particularly those more severely affected, are subjected to an increased adrenergic stimulus to the cardiovascular system which disappears with therapy. There is no evidence of positive inotropic action of sulphonylurea drugs in this study.

Inhibition of Na+-K+ Pump and L-Type Ca2+ Channel by Glibenclamide in Guinea Pig Ventricular Myocytes

“…Similar inhibitory effect of 10 to 100 M glibenclamide on the I Ca,L was also observed in rat aortic smooth muscle (Yoshitake et al, 1991;Bian and Hermsmeyer, 1994). Some investigators did not observe a negative inotropic effect of glibenclamide in the heart (Sykes et al, 1977;Del Valle et al, 2001). They applied glibenclamide via oral administration or intravenous injection, and the concentration of glibenclamide in plasma might be around 0.5 to 2.5 M (Del Valle et al, 2001).…”

Measurement of systolic time intervals.

“…In recent years, the use of the measurement of systolic time intervals (STI) as a measure of cardiac contractility has become increasingly more popular (Dobbs, Kenyon & Dobbs, 1977;Lewis, Milne & Goldberg, 1976;Sykes, Wright, Malins & Pentecost, 1977 The data leading to these regression equations were obtained from a large number of normal male subjects (similar data were obtained from female subjects) with the recordings being made between 08.00 and 10.00 h, although the latter time could be extended to 15.00 h. This technique has been applied to investigations into the pharmacodynamic effects of digoxin and beta methyl digoxin in man (Das, Talmers & Weissler, 1977;Hinderling & Garrett, 1977) where the shortening of QS2 or LVET has been used as a measure of the cardiac effects of these drugs. However position following a 10 min rest period.…”

Diabetic heart disease: The clinical and pathological spectrum—Part I

“…As blood glucose normalizes in newly treated diabetics, the heart rate-corrected pre-ejection period (PEP), QS, interval, and left ventricular ejection time increase and become closer to normal. 47 Average resting ejection fraction is higher with hyperglycemia than with normoglycemia in insulin-dependent diabetes mellitus (IDDM) patients. 48 An interesting animal model correlate has been observed: diabetic cardiomyopathies in rats can be prevented49 and even reversedSo by treatment with insulin.…”