Antithrombotic therapy for patients with atrial fibrillation and atherothrombotic vascular disease: striking the right balance between efficacy and safety

Atrial fibrillation (AF), the most prevalent cardiac arrhythmia, is estimated to affect 1.5% to 2.0% of the general population, that is, at least 100 million people worldwide.1 Left untreated, patients with nonvalvular AF (NVAF) are exposed to an annual risk of thromboembolic stroke of ≈5%, resulting in 5 million AF-related strokes each year.1 Properly dosed anticoagulation (eg, warfarin adjusted to an international normalized ratio of 2.0–3.0) is extremely effective in preventing AF-related strokes, reducing risk by two thirds compared with no therapy and by one-half compared with aspirin.1 In contrast, aspirin alone achieves a 21% relative reduction in risk of nonfatal stroke compared with no treatment, and aspirin plus clopidogrel yields an additional 11% reduction compared with aspirin alone.1 Thus, anticoagulation is the unchallenged current treatment of choice for patients with NVAF at moderate to high risk of thromboembolic complications.