Digoxin has traditionally been the
drug of choice for ventricular rate control in patients with chronic
atrial fibrillation (AF), with or without
heart failure (HF) with systolic dysfunction. In patients with permanent AF,
digoxin monotherapy is ineffective to control ventricular rate during exercise, but the combination of
digoxin with a beta-blocker or a non-
dihydropyridine calcium channel antagonist can control heart rate both at rest and during exercise. Only a few randomised, controlled studies have evaluated the adverse effects of
digoxin in patients with AF in a systematic way and side effects requiring
drug withdrawal have rarely been reported. When reported, the most frequent adverse effects were
cardiac arrhythmias (ventricular arrhythmias,
AV block of varying degrees and sinus pauses). This evidence suggested that, in contrast to other
antiarrhythmic drugs,
digoxin is a safe
drug in patients with AF. However, this safety profile can be erroneous due to the short follow-up of the studies and patient selection. Because patients with HF have been excluded in most studies, the safety profile of
digoxin in this population has not been directly addressed. Early recognition that an
arrhythmia is related to
digoxin intoxication as well as recognition of concomitant medications or medical conditions that may directly alter the pharmacokinetic profile of
digoxin, or indirectly alter its cardiac effects by pharmacodynamic interactions remain essential for safe and effective use of
digoxin in patients with AF.