Abstract：
Current guidelines exclusively recommend vitamin-K-antagonists (VKA) as anticoagulation for patients after mechanical aortic valve replacement due to the increased postoperative risk of valve thrombosis and thrombo-embolism. Strict and regular assessments are mandatory during VKA therapy to ensure a potent anticoagulatory effect within the desired range. From the patients\' perspective, VKA are associated with relevant interactions and side effects reducing the quality of life and contributing to a high number of patients not achieving the optimal therapeutic target. Direct oral anticoagulants (DOAC) have replaced VKA therapy in the past for several indications, e.g., atrial fibrillation. However, it is still unclear if DOACs could replace VKA therapy in patients after mechanical aortic valve replacement. While the PROACT-Xa study did not show a sufficient anticoagulatory effect of apixaban plus aspirin compared to VKA therapy in patients after mechanical aortic valve replacement, the direct thrombin inhibitor dabigatran and the oral factor Xa inhibitors apixaban and rivaroxaban showed promising results in comparable patient cohorts in smaller studies and case reports. Factor Xa inhibitors were able to prevent thrombosis and thrombo-embolic events in patients after mechanical aortic valve replacement. Therefore, factor Xa inhibitors or factor XI inhibitors could provide a potent alternative to VKA for patients after a mechanical aortic valve replacement.
摘要：
由于术后瓣膜血栓形成和血栓栓塞的风险增加，目前的指南仅推荐维生素K拮抗剂（VKA）作为机械主动脉瓣置换术后患者的抗凝药物。在VKA治疗期间必须进行严格和定期的评估，以确保在所需范围内的有效抗凝作用。从病人的角度来看，VKA与降低生活质量的相关相互作用和副作用相关,并导致大量患者未实现最佳治疗目标。直接口服抗凝药（DOAC）已取代VKA治疗在过去的几个适应症，例如，心房颤动。然而,目前尚不清楚DOAC能否替代机械主动脉瓣置换术后患者的VKA治疗.虽然在机械主动脉瓣置换术后的患者中，与VKA治疗相比，PROACT-Xa研究未显示阿哌沙班加阿司匹林的抗凝作用。在规模较小的研究和病例报告中,直接凝血酶抑制剂达比加群和口服因子Xa抑制剂阿哌沙班和利伐沙班在可比的患者队列中显示了有希望的结果.Xa因子抑制剂能够预防机械主动脉瓣置换术后患者的血栓形成和血栓栓塞事件。因此,Xa因子抑制剂或XI因子抑制剂可以为机械主动脉瓣置换术后的患者提供VKA的有效替代方案.
