- New onset atrial fibrillation (within 48 hours), persist for at least 1 hour, ventricular rate 120 beats per min or more without evidence of volume depletion (CVP 8 mmHg or more or receive volume resuscitation about 20-30 ml/kg), oxygen saturation not less than 90%, serum Potassium level between 3.0-5.0 mEq/l, serum Calcium level between 8.0-11.0 mg/dl