Restacorin is a recently developed effective antiarrhythmic agent with primarily class Ic properties. The present paper reviews the electrophysiologic and hemodynamic effects of this compound. The major electrophysiologic effects are a depression of V-max and an increase in AH, HV and QRS duration. The administration of restacorin does not induce significant side effects. In subjects with a normal left ventricular function, restacorin does not show negative inotropic effects. However, in patients with a decreased left ventricular function, restacorin produces a moderate negative inotropic effect