Pharmacotherapy of atrial fibrillation: a pathophysiological perspective and review

Atrial fibrillation (AF) is one of the most common arrhythmia encountered in clinical practice. Although AF is due to the structural and electrophysiological alterations in the atria, its sustainability is multifactorial, and the actual mechanisms are still not clear. Despite the recent advances in catheter ablation technology and techniques, pharmacotherapy still remains the first-line therapy for the management of AF. Current pharmacotherapy targets ion channel alterations that in fact represent only one aspect of the management of this complex arrhythmia. Successful pharmacological treatment of AF and restoration of sinus rhythm is limited and is in part due to its potential deleterious side effects. Newer agents having diverse mechanisms acting on the recently uncovered pathophysiological processes are on the horizon. These include atrial repolarization delaying agents, newer class III agents, Na(+)-Ca(2+) channel blockers, stretch receptor blockers, I(KACH) blockers, gap junction modifiers, upstream therapies, and agents targeting ischemia-induced AF. Gene- and cell-specific therapies including 'tailored nanopharmacy,' newer rate control medications with minimal side effects and the emergence of novel drugs targeting multiple areas of AF arrhythmogenesis in tandem with electrical therapy may be the future direction in the management of AF.