The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study: approaches to control rate in atrial fibrillation

J Am Coll Cardiol. 2004 Apr 7;43(7):1201-8. doi: 10.1016/j.jacc.2003.11.032.


Objectives: We sought to evaluate approaches used to control rate, the effectiveness of rate control, and switches from one drug class to another in the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study.

Background: The AFFIRM study showed that atrial fibrillation (AF) can be treated effectively with rate control and anticoagulation, but drug efficacy to control rate remains uncertain.

Methods: Patients (n = 2,027) randomized to rate control in the AFFIRM study were given rate-controlling drugs by their treating physicians. Standardized rate-control efficacy criteria developed a priori included resting heart rate and 6-min walk tests and/or ambulatory electrocardiographic results.

Results: Average follow-up was 3.5 +/- 1.3 years. Initial treatment included a beta-adrenergic blocker (beta-blocker) alone in 24%, a calcium channel blocker alone in 17%, digoxin alone in 16%, a beta-blocker and digoxin in 14%, or a calcium channel blocker and digoxin in 14% of patients. Overall rate control was achieved in 70% of patients given beta-blockers as the first drug (with or without digoxin), 54% with calcium channel blockers (with or without digoxin), and 58% with digoxin alone. Adequate overall rate control was achieved in 58% of patients with the first drug or combination. Multivariate analysis revealed an association between first drug class and several clinical variables. There were more changes to beta-blockers than to the other two-drug classes (p < 0.0001).

Conclusions: Rate control in AF is possible in the majority of patients with AF. Beta-blockers were the most effective drugs. To achieve the goal of adequate rate control in all patients, frequent medication changes and drug combinations were needed.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adrenergic beta-Antagonists / therapeutic use
  • Aged
  • Anti-Arrhythmia Agents / therapeutic use
  • Atrial Fibrillation / physiopathology*
  • Atrial Fibrillation / therapy
  • Calcium Channel Blockers / therapeutic use
  • Catheter Ablation
  • Digoxin / therapeutic use
  • Drug Therapy, Combination
  • Electrocardiography, Ambulatory
  • Female
  • Follow-Up Studies
  • Heart Rate / drug effects
  • Heart Rate / physiology*
  • Humans
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Pacemaker, Artificial
  • Stroke Volume / drug effects
  • Stroke Volume / physiology
  • Treatment Outcome


  • Adrenergic beta-Antagonists
  • Anti-Arrhythmia Agents
  • Calcium Channel Blockers
  • Digoxin