Propafenone—Clinical Electrophysiology and Efficacy in Patients with Documented or Potentially Life-threatening Arrhythmias

Propafenone is a new antiarrhythmic agent that inhibits the fast sodium channel and decreases phase 0 of the cardiac action potential. Since it has relatively little effect on the action potential duration, it has been classified as a type IC agent. Propafenone prolongs electrocardiographic intervals including PR and QRS. In addition, atrial and ventricular refractory periods generally are lengthened. Initial reports suggest a favorable effect on suppressing conduction over accessory pathways. Propafenone has been shown to have effectiveness in suppressing life-threatening ventricular arrhythmias as well. Electrophysiological testing is useful, but data such as mode of induction and rate of induced tachycardia should be considered in addition to inducibility status.