Increased myocardial contractility during intravenous insulin infusion in type 1 (insulin-dependent) diabetic patients: an echocardiographic study.
On two occasions eight insulin-dependent diabetic patients were connected to an artificial beta-cell, and insulin was administered by continuous intravenous infusion at a rate of 2 mU/kg/min, producing a moderate hyperinsulinaemia (mean 116 microU/ml). At random, blood glucose was kept constant by concomitant glucose infusion, or allowed to decrease to a mean value of 5.3 mmol/l. M-mode echocardiography was performed before, at 90 and at 180 min of insulin infusion. Following the euglycaemic insulin infusion periods, the fractional shortening of the left ventricle increased from 38.2% to 41.0 and 40.2%, respectively (p less than 0.02). The diastolic diameter (pre-load) and end-systolic meridional wall stress (after-load) remained constant in this experiment. In contrast, no change in fractional shortening could be demonstrated during falling blood glucose, possibly because pre-load was altered to a significant degree during this experimental condition. In conclusion, concomitant infusion of insulin and glucose, producing an euglycaemic hyperinsulinaemia, is followed by increased myocardial contractility.
Thuesen
L
L
University Department of Cardiology, Aarhus Kommunehospital, Denmark.
Christiansen
J S
JS
Schmitz
O
O
Christensen
N J
NJ
Orskov
H
H
Henningsen
P
P
D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy / Q000503:physiopathology*; D004452:Echocardiography; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage* / Q000097:blood; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*
D001786:Blood Glucose; D007328:Insulin