Anticoagulation Clinic, University of New Mexico Health Sciences Center, 1 University of New Mexico MSC, 07 4025, Albuquerque, NM 87131, USA.
Thromb Res. 2012 Jan;129(1):9-16. doi: 10.1016/j.thromres.2011.09.023. Epub 2011 Oct 21.
Nonvalvular atrial fibrillation is the most common clinically significant cardiac arrhythmia in the United States. It increases both the risk for and the severity of strokes and is associated with substantial morbidity, mortality, decreased quality of life, and related health care costs. Guidelines recommend anticoagulation therapy for the majority of patients with atrial fibrillation. Clinical trials have established that vitamin K antagonists are effective for stroke prevention for patients with atrial fibrillation for whom anticoagulation is recommended. However, vitamin K antagonists remain underutilized for a variety of reasons, including drug, physician, and patient factors. While vitamin K antagonists considerably reduce the risk of stroke, the absolute risk reduction varies according to individual patient risk factors. Accurately assessing each patient's true risk of stroke and bleeding is essential when determining which (if any) antithrombotic strategy should be used. Several stroke risk stratification schemes exist; of these, CHADS(2) is widely employed and simple. New, more sophisticated schemes may generate more precise risk estimates and better identify those patients for whom anticoagulant therapy offers a net clinical benefit. More studies are needed to determine the utility of bleeding risk stratification systems, as well as the role of surgical and interventional alternatives to anticoagulation treatment. Several novel oral anticoagulants are in (or have completed) phase 3 clinical trials. Dabigatran etexilate, approved in the United States in October 2010 for reducing the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, now offers the first oral alternative to warfarin for patients with atrial fibrillation.
非瓣膜性心房颤动是美国最常见的具有临床意义的心律失常。它增加了中风的风险和严重程度，并与大量的发病率、死亡率、生活质量下降以及相关的医疗保健费用有关。指南建议对大多数心房颤动患者进行抗凝治疗。临床试验已经证实，维生素 K 拮抗剂对推荐抗凝的心房颤动患者预防中风是有效的。然而，由于多种原因，维生素 K 拮抗剂的应用仍然不足，包括药物、医生和患者因素。虽然维生素 K 拮抗剂大大降低了中风的风险，但绝对风险的降低因个体患者的危险因素而异。在确定应使用哪种（如果有）抗血栓形成策略时，准确评估每个患者中风和出血的真正风险至关重要。存在几种中风风险分层方案；其中，CHADS(2) 被广泛应用且简单。新的、更复杂的方案可能会产生更精确的风险估计，并更好地识别出那些抗凝治疗有净临床获益的患者。需要更多的研究来确定出血风险分层系统的效用，以及手术和介入替代抗凝治疗的作用。几种新型口服抗凝剂正在（或已完成）3 期临床试验。达比加群酯于 2010 年 10 月在美国获得批准，用于降低非瓣膜性心房颤动患者中风和全身性栓塞的风险，现在为心房颤动患者提供了华法林的第一个口服替代药物。
