Stroke Prevention in Nonvalvular€Atrial€Fibrillation

Ischemic stroke in patients with atrial fibrillation is associated with substantial morbidity and mortality. The growing epidemic of atrial fibrillation worldwide has raised concerns about the dire need for effective stroke prevention systems in these patients. Fortunately, the last decade has witnessed a plethora of data on novel stroke prevention methods in patients with nonvalvular atrial fibrillation. However, optimal selection and effective implementation of these preventative strategies require an integrative approach that takes into account not only the available clinical data but also the perspective of each of the stakeholders involved (patient, physician, and society). The goal of this review was to discuss the contemporary issues surrounding stroke prevention in atrial fibrillation from the perspective of these 3 major stakeholders. (J Am Coll Cardiol 2018;71:2790–801) © 2018 by the American College of Cardiology Foundation. P revention of stroke in the setting of nonvalvular atrialfibrillation (AF) is a priority for physicians, patients, and their families, as well as society at large, because of the considerable associatedmorbidity andmortality. A number of strategies have been developed, some of which are complementary but others of which are competitive with each other. Selection of the optimal approach needs to consider not only the quality of the available data but also individual patient preferences. In that latter discussion, evaluation of the risks and benefits of the different strategies may vary dramatically among patients and among the other stakeholders. Although there is a plethora of clinical data on stroke prevention in AF, none has considered this issue by using an integrative multi-stakeholder approach. The purpose of the present paper is to review the issues surrounding stroke prevention in patients with AF from the perspectives of 3 major stakeholders: patient, physician, and society. STROKE AND AF: SCOPE OF THE PROBLEM AF, the most common sustained cardiac arrhythmia (1), is emerging as a growing epidemic (1–4). The rising prevalence of AF is more pronounced in high-income countries, and >12 million patients are projected to have AF in the United States by 2030 (Figure 1) (5). Stroke is the most debilitating complication of AF. Up to 125,000 strokes annually in the United States are attributed to AF (6), and 40% of all strokes in patients >80 years of age are related to AF (6,7). Furthermore, the prevalence of AF among patients admitted with acute ischemic stroke (AIS) has increased from 16% in 2003 to 20% in 2014 (Figure 2) (8). The impact of AF-associated stroke is substantial on patients, physicians, and society at large: 1) Impact on patients: AF-associated strokes are more disabling, more likely to recur, and are associated with significantly higher mortality than non–AF-associated strokes (6–11). In some studies, 15% to 20% of AF-associated strokes were fatal (7,12). In a large observational study, at 5 years only 2 in 5 AIS patients with AF were alive, and 1 in 5 had experienced recurrent stroke (13). Despite the improvement in AIS-related mortality overall, the differential negative impact of AF on the morbidity and mortality and cost of AIS was steady over the last decade (Figure 2). 2) Impact on physicians: Stroke prevention in patients with AF poses an ongoing challenge to physicians because it requires continuous personalized risk/benefit assessment, extended discussions for informed shared decision-making, repeated counseling on medication adherence, and monitoring of anticoagulation among other issues. Clinicians are also faced with grim statistics when it comes to the undertreatment of AF with oral anticoagulants (OACs). In a national quality improvement U.S. registry (the National Cardiovascular Data Registry–PINNACLE registry), OAC prescription prevalence did not exceed 50% even in higher risk patients (14). Only one-half of OACeligible patients with AF are prescribed OACs in line with guidelines (15). In a large U.S. commercial insurance database, adherence to anticoagulation was poor in practice and only modestly improved with non–vitamin K antagonist oral anticoagulants FIGURE 1 Projected Number United States (Millions) Pr oj ec te d Nu m be r o f P er so ns w ith A F (M ill io ns ) 200