Verheugt Freek
Universitair Medisch Centrum St Radboud, afd. Cardiologie, Nijmegen, The Netherlands.
Ned Tijdschr Geneeskd. 2011;155:A2143.
Cerebral infarction is the most serious complication of atrial fibrillation. Coumarin derivatives (vitamin K antagonists) counteract systemic thromboembolism and reduce the risk of stroke by more than 60%, but carry a risk of serious bleeding. Antiplatelet therapy and subcutaneous low-molecular-weight heparin are as yet not sufficiently effective and are associated with a bleeding risk similar to vitamin K antagonists. Vitamin K antagonists require intensive INR monitoring to ensure efficacy and safety. In the past decade, oral agents have been developed that directly inhibit the activity of thrombin (factor IIa) and of activated factor X (Xa), which is the first compound in the final common pathway of the coagulation cascade. These do require INR monitoring and have rapid onset and offset of action. The first results with thrombin blockers, such as dabigatran, look promising in efficacy and safety and Xa inhibitors are currently under investigation in atrial fibrillation in 3 large clinical trials. Long-term safety of the new agents in patients with atrial fibrillation has not yet been determined.
脑梗死是心房颤动最严重的并发症。香豆素衍生物（维生素K拮抗剂）可对抗全身性血栓栓塞，并将中风风险降低60%以上，但存在严重出血风险。抗血小板治疗和皮下注射低分子量肝素目前效果尚不充分，且出血风险与维生素K拮抗剂相似。维生素K拮抗剂需要密切监测国际标准化比值（INR）以确保疗效和安全性。在过去十年中，已开发出口服药物，可直接抑制凝血酶（因子IIa）和活化因子X（Xa）的活性，Xa是凝血级联反应最终共同途径中的首个化合物。这些药物无需监测INR，起效和失效迅速。凝血酶阻滞剂（如达比加群）的初步结果在疗效和安全性方面看起来很有前景，Xa抑制剂目前正在3项大型临床试验中用于心房颤动的研究。新型药物对心房颤动患者的长期安全性尚未确定。
