Enhanced sensitivity to drug-induced QT interval lengthening in patients with heart failure due to left ventricular systolic dysfunction.

ABSTRACT: Patients with heart failure (HF) are at increased risk for drug-induced torsades de pointes (TdP) due to unknown mechanisms. Our objective was to determine if sensitivity to drug-induced QT interval lengthening is enhanced in patients with HF. In this multicenter, prospective study, 15 patients with atrial fibrillation or flutter requiring conversion to sinus rhythm were enrolled: 6 patients with New York Heart Association class II to III HF (mean ejection fraction [EF], 30% ± 9%), and 9 controls (mean EF, 53% ± 6%). Patients received ibutilide 1 mg intravenously. Blood samples and 12-lead electrocardiograms were obtained prior to and during 48 hours postinfusion. Serum ibutilide concentrations at 50% maximum effect on Fridericia-corrected QT (QT(F)) intervals (EC(50)) were determined, and

SUBMITTER: Tisdale JE 

PROVIDER: S-EPMC3857021 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature