Effect of acute hyperinsulinemia on ventricular repolarization in uncomplicated obesity

Background: Acute hyperinsulinemia has been shown to increase QTc interval in lean subjects, but data on obese subjects are still unclear. Aim of this study was to evaluate the effect of acute hyperinsulinemia on QTc interval and QTc dispersion in uncomplicated obesity. Methods: We calculated QTc duration and QTc dispersion in 30 uncomplicated obese subjects (mean age 32.2±7, BMI 36.7±9.4 kg/m2) by measurements of 12-lead ECG recording during a euglycemic hyperinsulinemic clamp. Results: Insulin infusion during the clamp did not significantly modify QTc interval and QTc dispersion in uncomplicated obese subjects (401.5±29.2 vs. 413.7±30.5; 35.4±10.5 vs. 38.7±14.5, respectively). Conclusions: Acute hyperinsulinemia seems to no significantly affect ventricular repolarization in uncomplicated obesity. Insulin resistance and the absence of diabetes and hypertension could explain, at least in part, this finding.