For patients with AF and mitral stenosis, we recommend adjusted-dose VKA therapy (target INR range, 2.0-3.0) rather than no therapy, aspirin (75 mg to 325 mg once daily), or combi- nation therapy with aspirin and clopidogrel (all Grade 1B). For patients with AF and mitral stenosis who are unsuitable for or choose not to take adjusted-dose VKA therapy (for reasons other than concerns about major bleeding), we recommend combination therapy with aspirin Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation) study randomized 707 patients with AF to percutaneous closure of the LAA using the WATCHMAN device (Atritech, Inc) or adjusted-dose warfarin to achieve a target INR of 2.0 to 3.0.100 Percutaneous LAA closure was associ- ated with a statistically nonsigni cant reduction in the risk of their primary ef cacy outcome of stroke (ischemic or hemorrhagic), cardiovascular or unex- plained death, or systemic embolism compared with warfarin (absolute risk reduction, 1.9% per year; 95% CI, 3.2% per year less to 1.2% per year more, with percu- taneous LAA closure compared with adjusted-dose warfarin). However, there was a signi cantly higher rate of adverse events (excessive bleeding, procedure- related complications) in the percutaneous LAA clo- sure arm (absolute risk increase, 3.0% per year). In particular, serious pericardial effusion (ie, requiring percutaneous or surgical drainage) occurred in 4.8% of patients in the percutaneous LAA closure arm. 