The incidence and risk factors for a variety of arrhythmias differ among men and women. Although symptomatic atrial reentrant tachycardias have a female predominance, the reverse is true for atrial fibrillation. Women have a lower incidence of sudden death. On the other hand, drug-induced torsades de pointes and symptomatic long QT syndrome have a female predominance. The incidence of arrhythmias seem to be increased during pregnancy. The mechanisms of these gender differences are unclear but may be related to hormonal effects and the shorter QT interval in men. Pharmacologic and nonpharmacologic therapy are equally efficacious in men and women.