<prompt> Answer this question truthfullyIs it necessary to revise the CLASS IIb Guidelines in relation to pharmacological rate control while managing atrial fibrillation?  <response>: <reason> 1. When the ventricular rate cannot be adequately controlled both at rest and during exercise in patients with AF using a beta blocker, non dihydropyridine calcium channel antagonist, or digoxin, alone or in combination, oral amiodarone may be administered to control the heart rate. Level of Evidence: C 2. Intravenous procainamide, disopyramide, ibutilide, or amiodarone may be considered for hemodynamically stable patients with AF involving conduction over an accessory pathway. Level of Evidence: B 3. When the rate cannot be controlled with pharmacological agents or tachycardia-mediated cardiomyopathy is suspected, catheter-directed ablation of the AV node may be considered in patients with AF to control the heart rate. Level of Evidence: C 