Atrial fibrillation should be controlled with a ventricular rate of at least 100-120 beats per minute. Patients with atrial fibrillation usually have a ventricular rate of 120-160 beats per minute, and in severe cases, 300-600 beats per minute, which is a common persistent arrhythmia. Drugs that are effective in controlling the ventricular rate in patients with atrial fibrillation include digitalis, beta-blockers, and dihydropyridine calcium antagonists, all of which can control the ventricular rate to less than 120 beats per minute in severe atrial fibrillation.