EFFICACY OF AJMALINE AND PROPAFENONE IN PATIENTS WITH ACCESSORY PATHWAYS - A PROSPECTIVE RANDOMIZED STUDY

In a prospective randomized study, we assessed the electrophysiologic effects and the efficacy of ajmaline versus propafenone in patients wi th accessory pathways (APs). During initiated atrioventricular (AV) re entrant tachycardia or atrial fibrillation (AF), ajmaline (1 mg/kg as bolus followed by infusion of 15 mu g/kg/min) or propafenone (2 mg/kg, followed by infusion of 30 mu g/kg/min.) were randomly administered i ntravenously (i.v.) in 40 patients with APs. AV reentrant tachycardia terminated in 15 of 16 patients (94%) on ajmaline and in 12 of 15 pati ents (80%, NS) on propafenone. AF ceased in 4 of 4 patients receiving ajmaline and in 3 of 5 patients receiving propafenone (n.s.). During c ontinuous infusion of drugs, AV reentrant tachycardia became noninduci ble in 10 (50%) patients receiving ajmaline, as compared with 6 (32%) receiving propafenone (NS). Both drugs significantly prolonged the ant erograde and retrograde effective refractory periods (ERPs) of the AP. There were no significant differences in changes in electrophysiologi c parameters between the two drugs. Ajmaline and propafenone are highl y effective and safe in terminating and preventing reinitiation of AV reentrant tachycardia or AF in patients with APs. Both drugs significa ntly prolonged the anterograde and retrograde ERPs of the APs.