Drugs and the QTc interval

DRUGS AND QTc INTERVAL DISPERSION

The measure of delayed ventricular repolarization most frequently used clinically is the ability of the new chemical entity to prolong the QTc interval on surface electrocardiogram. Intramyocardial dispersion of repolarization appears to play a more important role both in electrical stability of the ventricles and in arrhythmogenesis. The potential importance of myocardial dispersion of refract...

THE CLINICAL EVALUATION OF QT/QTc INTERVAL PROLONGATION AND PROARRHYTHMIC POTENTIAL FOR NON-ANTIARRHYTHMIC DRUGS

Ketamine-induced QTc interval prolongation

Sir, Ketamine is a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor. It is widely used as a dissociative anesthetic and is also used as an adjunct in pain management, particularly in opioid-tolerant patients. It blocks calcium channels and depresses sodium channel function as well as having anticholinergic effects. It inhibits the re-uptake of the catecholamines and may hav...

Insulin prolongs the QTc interval in humans.

Insulin hyperpolarizes plasma membranes; we tested whether insulin affects ventricular repolarization. In 35 healthy volunteers, we measured the Q-T interval during electrocardiographic monitoring in the resting state and in response to hyperinsulinemia (euglycemic 1-mU. min(-1). kg(-1) insulin clamp). A computerized algorithm was used to identify T waves; Bazett's formula was employed to corre...

The importance of correct QTc measurement in elderly patients treated with QT interval prolonging drugs.

J U L Y 2 0 1 4 , V O L . 7 2 , N O 6 © Van Zuiden Communications B.V. All rights reserved. To the Editor, We read with interest the recently published article by Kan et al. In this review, the authors address the identification and management of drug-intoxicated patients who may be at risk for prolongation of the QT interval corrected for heart rate (QTc) and possible torsades de pointes (TdP)...