New Therapies for Stroke Prevention in Atrial Fibrillation

Atrial fibrillation is the most frequent sustained arrhythmia seen in clinical practice, and the public health implications of this growing epidemic are sobering. Approximately 2.3 to 3.2 million people are currently affected in the United States; the risk of stroke ranges from 1% to 7% per year; and atrial fibrillation accounts for ≈45% of embolic strokes annually, which amounts to ≈100 000 strokes per year.1,2 Moreover, atrial fibrillation is an independent predictor of mortality in most studies.3Article see p 1029 Atrial fibrillation is a frequent cause for hospitalization, and during the last 2 decades, hospitalization rates for atrial fibrillation as the principal diagnosis have increased substantially.4,5 The economic consequences of this disorder are substantial.6 In the United Kingdom, the cost of hospitalizations for atrial fibrillation increased 123% between 1995 and 20007 and in 1995 accounted for 0.62% of the entire budget of the National Health Service.Future projections are even more disturbing. The prevalence of atrial fibrillation increases with age, and the demographic tide around the world is resulting in increasingly aging societies. Moreover, the age-adjusted incidence and prevalence of atrial fibrillation in Olmsted County have increased significantly between 1980 and 2000, and on the basis of these projections, the number of persons with atrial fibrillation could exceed 12 million by 2050.1 It is estimated that 35% of the increased prevalence is due to an increased incidence, 43% to the result of greater longevity, and 22% to a growing census. In summary, atrial fibrillation is a costly disease from both a clinical and economic perspective, and the burden is increasing. There is a dire need for new therapies and preventive approaches.In atrial fibrillation, the primary therapeutic objectives are to prevent stroke and to improve symptoms, whether by controlling the ventricular response rate …