Department of Cardiology, Quebec Heart and Lung Institute, Laval University, Quebec City, Quebec, Canada.
Division of Cardiology, University of Vermont College of Medicine, Burlington, Vermont.
J Am Coll Cardiol. 2013 Dec 24;62(25):2349-2359. doi: 10.1016/j.jacc.2013.03.029. Epub 2013 Apr 10.
Transcatheter aortic valve implantation (TAVI) has emerged as a therapeutic alternative for patients with symptomatic aortic stenosis at high or prohibitive surgical risk. However, patients undergoing TAVI are also at high risk for both bleeding and stroke complications, and specific mechanical aspects of the procedure itself can increase the risk of these complications. The mechanisms of periprocedural bleeding complications seem to relate mainly to vascular/access site complications (related to the use of large catheters in a very old and frail elderly population), whereas the pathophysiology of cerebrovascular events remains largely unknown. Further, although mechanical complications, especially the interaction between the valve prosthesis and the native aortic valve, may play a major role in events that occur during TAVI, post-procedural events might also be related to a prothrombotic environment or state generated by the implanted valve, the occurrence of atrial arrhythmias, and associated comorbidities. Antithrombotic therapy in the setting of TAVI has been empirically determined, and unfractionated heparin during the procedure followed by dual antiplatelet therapy with aspirin (indefinitely) and clopidogrel (1 to 6 months) is the most commonly recommended treatment. However, bleeding and cerebrovascular events are common; these may be modifiable with optimization of periprocedural and post-procedural pharmacology. Further, as the field of antiplatelet and anticoagulant therapy evolves, potential drug combinations will multiply, introducing variability in treatment. Randomized trials are the best path forward to determine the balance between the efficacy and risks of antithrombotic treatment in this high risk-population.
经导管主动脉瓣植入术（TAVI）已成为高危或极高危手术风险的有症状主动脉瓣狭窄患者的一种治疗选择。然而，接受 TAVI 的患者也有较高的出血和中风并发症风险，并且该手术本身的特定机械方面会增加这些并发症的风险。围手术期出血并发症的机制似乎主要与血管/入路部位并发症（与在非常年老和脆弱的老年人群中使用大导管有关）有关，而脑血管事件的病理生理学仍知之甚少。此外，尽管机械并发症，特别是瓣膜假体与原生主动脉瓣之间的相互作用，可能在 TAVI 期间发生的事件中起主要作用，但术后事件也可能与植入瓣膜引起的促血栓形成环境或状态、房性心律失常的发生以及相关合并症有关。TAVI 中的抗血栓治疗是根据经验确定的，在手术过程中使用普通肝素，然后使用阿司匹林（无限期）和氯吡格雷（1 至 6 个月）进行双联抗血小板治疗是最常推荐的治疗方法。然而，出血和脑血管事件很常见；通过优化围手术期和术后药理学可以减少这些事件的发生。此外，随着抗血小板和抗凝治疗领域的发展，潜在的药物组合将会增加，从而导致治疗的变异性。随机试验是确定这种高危人群中抗血栓治疗的疗效和风险之间平衡的最佳途径。
