Rate Versus Rhythm Control Pharmacotherapy For Atrial Fibrillation: Where are We in 2008?

Abstract

Atrial fibrillation (AF) is the most common sustainedcardiac rhythm disturbance encountered by physicians. The management of AF isfocused on control of heart rate, correction of rhythm disturbance, andrisk-determined prophylaxis of thromboembolism. The goals of AF therapy are, aswith other serious disorders, to reduce mortality (if possible) and morbidity(improve quality of life, [QOL]). To this end, several large studies haveexamined rhythm-control versus rate-control strategies. Although a survivaladvantage to using rhythm control with currently available antiarrhythmic drugshas not been proven, neither has there been a significant excess risk versusrate control. Therefore, using our current therapies, the results have notsupported rate control or rhythm control as being a preferable first-linetherapy for AF as regards survival; importantly, neither do they disprove the hypothesis thatmaintenance of sinus rhythm is preferable to the continuation of AF,particularly if rate control fails to restore adequate QOL. Many post-hocanalyses and substudies have assessed QOL, functional status, and exercisetolerance, with the majority demonstrating important benefits associated withachievement of rhythm control. This review examines rate and rhythm controloptions, the clinical outcomes of several important AF trials, discusses thelimitations in applying the major morbidity/mortality findings to everydayclinical practice, and summarizes the lessons learned.