Taking the Pulse of Atrial Fibrillation: A Practical Approach to Rate Control

Abstract

Despite major advances in atrial fibrillation (AF) catheter ablation, rate control remains the most widely used management strategy for AF in the general population. In addition to its use as a primary approach to control symptoms and prevent complications of AF, rate control is often a necessary complement to rhythm-control strategies, especially with antiarrhythmic drugs. The value of rate-control therapy is supported by several large randomized clinical trials showing no difference in major cardiovascular outcomes between rate-control and rhythm-control strategies with currently available therapeutic approaches (antiarrhythmic drugs and/or catheter ablation). Despite its extensive use, the rational basis for rate-control therapy is underemphasized in clinical teaching and practice. In this article, we aim to provide evidence-based thoughts on important practical aspects of rate-control therapy in AF by reviewing 5 clinically relevant issues. We (1) highlight the pharmacological differences between the mechanisms of action of β-blockers and Ca²⁺-channel blockers for AF rate control and the practical implications for therapeutic decision making; (2) review the controversies surrounding the use of digoxin for AF rate control in the light of recently published work; (3) discuss the evidence for rate-control heart rate targets in patients with AF and preserved left-ventricular function; (4) examine how heart rate targets may differ in patients with heart failure and reduced vs preserved left-ventricular ejection fraction and the importance of heart-rate lowering for the effectiveness of cardiac resynchronization therapy in patients with heart failure and AF; (5) discuss the relationship between AF, exercise capacity, and rate-controlling drug class.