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Updated: Jun 10, 2026

Contractions of Human-iPSC-derived Cardiomyocyte Syncytia Measured with a Ca-sensitive Fluorescent Dye in Temperature-controlled 384-well Plates
Published on: October 18, 2018
[Ionic mechanisms of action of class III antiarrhythmic drugs]
Abstract:
In this review we discuss mechanisms of antiarrhythmic and adverse proarrhythmic action of class III drugs. Special attention is given to ionic currents and channels which determine specific features of their effects (IKr, IKa, IKur). We consider general patterns of changes of bioelectrical activity in atria and ventricles leading to development of arrhythmias or stabilization of rhythm. We also discuss value of QT interval as predictor of torsade de pointes. Perspectives and limitations of development of novel class III antiarrhythmic drugs are discussed as well. We present consideration of efficacy and mechanisms of action of such compounds as dronedarone and vernacalant suggested for termination of atrial fibrillation and maintenance of sinus rhythm. Special attention is given to RG 2 - a novel compound with class III activity.
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