Hemodynamic changes and time to reversion to sinus rhythm were studied in 30 patients with atrial fibrillation undergoing valve replacement. The patients were randomly divided into two equal groups. Propafenone (Class IC anti-arrhythmic) was given to one group at a dose of 1-2 mg/kg in 10 minutes followed by a maintenance dose of 1 mg/kg over the subsequent 48 hours. Amiodarone (Class III anti-arrhythmic) was given to the other group at a dose of 5-10 mg/kg in 10 minutes followed by a maintenance dose of 15 mg/kg over the subsequent 48 hours.There was no significant difference between the two groups as regards ABP, CVP, CO, CI, PAP, PCWP and the time to reversion to sinus rhythm. Some patients of both groups required the infusion of inotropic drugs as (Dobutamine 10-15 mug/kg/min or Adrenaline 0.01-0.1 mug/kg/min) without significant rise in one group than the other and some others required the infusion of vasodilators as nitroglycerin or Sodium Nitropruside