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* Objective: To compare the relative risks and benefits of several clinical strategies for managing patients with chronic atrial fibrillation. * Design: Five recent randomized controlled trials of warfarin in atrial fibrillation, 6 randomized controlled trials of quinidine, and 13 longitudinal studies of low-dose amiodarone were used. A MEDLINE search was also done (1966 to present). * Measurements: A Markov decision analysis model was used to assess outcomes in large, hypothetical cohorts of patients with atrial fibrillation followed from 65 to 70 years of age within four clinical strategies: 1) no treatment; 2) warfarin; 3) electrical cardioversion followed by quinidine to maintain normal sinus rhythm; and 4) electrical cardioversion followed by low-dose amiodarone. * Results: In this hypothetical cohort, fewer patients had disabling events with amiodarone (1.4%) than with quinidine (1.8%), warfarin (2.6%), or no treatment (7.4%). Amiodarone appeared to be associated with the lowest 5-year mortality (13.6%) when compared with warfarin (14.4%), quinidine (15.2%), and no treatment (18.2%). In terms of quality-adjusted life-years, amiodarone had the highest expected value (4.75 years), followed by warfarin (4.72 years), quinidine (4.68 years), and no treatment (4.55 years). Amiodarone remained the preferred strategy using the most plausible scenarios of risks associated with atrial fibrillation. Choices among warfarin, quinidine, and no treatment depended on estimates of bleeding rates with warfarin, stroke rates after discontinuing warfarin, quinidine-related mortality, and the quality of life with warfarin. * Conclusion: Cardioversion followed by low-dose amiodarone to maintain normal sinus rhythm appears to be a relatively safe and effective treatment for patients with chronic atrial fibrillation., Cardioversion and low-dose amiodarone may be an effective treatment for chronic atrial fibrillation. Atrial fibrillation is the rapid, random contraction of individual fibers of the heart muscle causing an irregular, rapid heart beat. Cardioversion is used to restore the normal rhythm of the heart by electrical shock. Researchers applied a decision analysis model to a hypothetical set of patients based on the patients of 24 studies. They evaluated the efficacy of no treatment, warfarin, cardioversion followed by quinidine and cardioversion followed by low-dose amiodarone. Among the hypothetical patients, 1.4% had disabling cardiac events with amiodarone, compared to 1.8% with quinidine, 2.6% with warfarin and 7.4% with no treatment. Amiodarone was also associated with the lowest five-year mortality rate (13.6%) and the highest expected value for quality-adjusted life years (4.75 years) when compared to the other treatments.

Background: Physicians managing patients with nonvalvular atrial fibrillation must consider the risks, benefits, and costs of treatments designed to restore and maintain sinus rhythm compared with those of rate control with antithrombotic prophylaxis. Objective: To compare the cost-effectiveness of cardioversion, with or without antiarrhythmic agents, with that of rate control plus warfarin or aspirin. Design: A Markov decision-analytic model was designed to simulate long-term health and economic outcomes. Data Sources: Published literature and hospital accounting information. Target Population: Hypothetical cohort of 70-year-old patients with different baseline risks for stroke. Time Horizon: 3 months. Perspective: Societal. Intervention: Therapeutic strategies using different combinations of cardioversion alone, cardioversion plus amiodarone or quinidine therapy, and rate control with antithrombotic treatment. Outcome Measures: Expected costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness. Results of Base-Case Analysis: Strategies involving cardioversion alone were more effective and less costly than those not involving this option. For patients at high risk for ischemic stroke (5.3% per year), cardioversion alone followed by repeated cardioversion plus amiodarone therapy on relapse was most cost-effective ($9300 per QALY) compared with cardioversion alone followed by warfarin therapy on relapse. This strategy was also preferred for the moderate-risk cohort (3.6% per year), but the benefit was more expensive ($18 900 per QALY). In the lowest-risk cohort (1.6% per year), cardioversion alone followed by aspirin therapy on relapse was optimal. Results of Sensitivity Analysis: The choice of optimal strategy and incremental cost-effectiveness was substantially influenced by the baseline risk for stroke, rate of stroke in sinus rhythm, efficacy of warfarin, and costs and utilities for long-term warfarin and amiodarone therapy. Conclusions: Cardioversion alone should be the initial management strategy for persistent nonvalvular atrial fibrillation. On relapse of arrhythmia, repeated cardioversion plus low-dose amiodarone is cost-effective for patients at moderate to high risk for ischemic stroke., Restoration of a normal heart rhythm, plus treatment with antiarrhythmic drugs or aspirin, most effectively reduce the risk of stroke in patients with nonvalvular atrial fibrillation. Atrial fibrillation is a disordered rhythm of the upper chambers of the heart. Researchers compared treatments for a hypothetical group of 70-year-old patients with the arrhythmia. Cardioversion, or the restoration of a normal sinus rhythm with an electric shock, was the most cost-effective treatment for all patients. Depending on the risk of stroke, patients may then benefit from drug therapy with amiodarone or aspirin to control the arrhythmia and reduce the formation of blood clots.