Torsade de pointes ("twisting of the points") is a ventricular tachycardia with QRS complexes of changing amplitude that seem to "twist" around the isoelectric line. It is a re-entrant arrhythmia associated with malfunction of ion channels involved in myocyte repolarization. Certain drugs may result in prolongation of the QT interval and development of torsades, especially if certain clinical or electrocardiographic findings are present.