[Ventricular tachyarrhythmia induced by low doses of sotalol: torsade de pointes or polymorphous ventricular tachycardia?].

A case of QT prolongation and ventricular tachyarrhythmia in a 57-year-old patient treated with small therapeutic doses of sotalol is reported. There was no concomitant treatment prolonging the QT interval. Hypokalemia could be excluded. Before treatment an electrophysiological study was performed, and ventricular tachycardia could not be initiated. Coronary artery disease was excluded. QT prolongation and ventricular tachyarrhythmias induced by small therapeutic doses of sotalol in normokalemia may occur on rare occasions. It may be problematic to differentiate between torsade de pointes and polymorphous ventricular tachycardia when describing such a ventricular tachyarrhythmia.