Exercise induced fatal sinusoidal ventricular tachycardia secondary to moricizine

Moricizine has been touted as having a low incidence of proarrhythmic effects. We present a case of proarrhythmia from moricizine, which presented as exercise induced ventricular tachycardia, and review the literature suggesting that this antiarrhythmic drug shares the proarrhythmic profile of other agents with predominant type Ic action. We conclude that moricizine has certain clinical and electrophysiological features that resemble type Ic antiarrhythmic agents. Precautions similar to those used when prescribing other drugs of this type should be followed when prescribing moricizine, including predischarge exercise testing.