A Case of Phenothiazine-induced Torsades de Pointes / 대한내과학회지

ABSTRACT

Torsades de pointes (TdP) is a form of polymorphic ventricular tachycardia associated with a prolonged QT interval or increased U wave. It may occur either in the congenital(idiopathic) form or in the aquired form. Although aquired TdP could be found in many clinical settings such as various drugs, bradycardia, or electrolyte imbalance, it is most commonly induced by drugs. The underlying mechanism is though to be the triggered activity arising as a consequence of early afterdepolarization. Phenothiazine has many derivatives that can lead to occur the cardiovascular events including hypotension, syncope, tachycardia and various ECG changes. Chloropromazine is a propylamine derivative of phenothiazine. We report a case of TdP occurred after chloropromazine usual dosage.