丹麦哥本哈根大学医院Ole De Backer研究组探索了经导管主动脉瓣置换术后小叶运动减少的预防方案。2019年11月16日，《新英格兰医学杂志》发表了这一最新研究成果。

生物人工主动脉瓣亚临床小叶增厚和小叶运动减少已由四维CT证实。抗凝治疗是否能减少经导管主动脉瓣置换术（TAVR）后该现象的发生尚不明确。

在这项大型随机试验的子研究中，研究组招募成功接受TAVR且无长期抗凝指征的患者，将其随机分组，分别接受利伐沙班+阿司匹林抗凝（利伐沙班组）或氯吡格雷+阿司匹林治疗（抗血小板组）。

研究组共招募了231例患者。治疗90天后，经四维CT评估，利伐沙班组97例患者中有2例（2.1%）观察到至少一个人工瓣膜小叶呈3级及以上活动度降低，抗血小板组101例患者中有11例（10.9%）；利伐沙班组中有12例（12.4%）观察到至少一个小叶增厚，抗血小板组中有33例（32.4%）。在主要试验中，利伐沙班组死亡或血栓栓塞事件的风险较高，风险比为1.35；危及生命、致残或大出血风险也较高，风险比为1.50。

总之，对于无长期抗凝指征的TAVR成功的患者，利伐沙班为基础的抗凝方案与抗血小板方案相比，可以更有效地预防亚临床小叶运动异常，但死亡或血栓栓塞等并发症以及出血的风险较高。

附：英文原文

Title: Reduced Leaflet Motion after Transcatheter Aortic-Valve Replacement

Author: Ole De Backer, M.D., Ph.D.,, George D. Dangas, M.D.,, Hasan Jilaihawi, M.D.,, Jonathon A. Leipsic, M.D.,, Christian J. Terkelsen, M.D., D.M.Sc., Ph.D.,, Raj Makkar, M.D.,, Annapoorna S. Kini, M.D.,, Karsten T. Veien, M.D.,, Mohamed Abdel-Wahab, M.D., Ph.D.,, Won-Keun Kim, M.D.,, Prakash Balan, M.D.,, Nicolas Van Mieghem, M.D., Ph.D.,, Ole N. Mathiassen, M.D., Ph.D.,, Raban V. Jeger, M.D.,, Martin Arnold, M.D.,, Roxana Mehran, M.D.,, Ana H.C. Guimares, Ph.D.,, Bjarne L. Nrgaard, M.D., Ph.D.,, Klaus F. Kofoed, M.D., D.M.Sc.,, Philipp Blanke, M.D.,, Stephan Windecker, M.D.,, and Lars Sndergaard, M.D., D.M.Sc.

Issue&Volume: November 16, 2019

Abstract:

Background

Subclinical leaflet thickening and reduced leaflet motion of bioprosthetic aortic valves have been documented by four-dimensional computed tomography (CT). Whether anticoagulation can reduce these phenomena after transcatheter aortic-valve replacement (TAVR) is not known.

Methods

In a substudy of a large randomized trial, we randomly assigned patients who had undergone successful TAVR and who did not have an indication for long-term anticoagulation to a rivaroxaban-based antithrombotic strategy (rivaroxaban [10 mg] plus aspirin [75 to 100 mg] once daily) or an antiplatelet-based strategy (clopidogrel [75 mg] plus aspirin [75 to 100 mg] once daily). Patients underwent evaluation by four-dimensional CT at a mean (±SD) of 90±15 days after randomization. The primary end point was the percentage of patients with at least one prosthetic valve leaflet with grade 3 or higher motion reduction (i.e., involving >50% of the leaflet). Leaflet thickening was also assessed.

Results

A total of 231 patients were enrolled. At least one prosthetic valve leaflet with grade 3 or higher motion reduction was found in 2 of 97 patients (2.1%) who had scans that could be evaluated in the rivaroxaban group, as compared with 11 of 101 (10.9%) in the antiplatelet group (difference, 8.8 percentage points; 95% confidence interval [CI], 16.5 to 1.9; P=0.01). Thickening of at least one leaflet was observed in 12 of 97 patients (12.4%) in the rivaroxaban group and in 33 of 102 (32.4%) in the antiplatelet group (difference, 20.0 percentage points; 95% CI, 30.9 to 8.5). In the main trial, the risk of death or thromboembolic events and the risk of life-threatening, disabling, or major bleeding were higher with rivaroxaban (hazard ratios of 1.35 and 1.50, respectively).

Conclusions

In a substudy of a trial involving patients without an indication for long-term anticoagulation who had undergone successful TAVR, a rivaroxaban-based antithrombotic strategy was more effective than an antiplatelet-based strategy in preventing subclinical leaflet-motion abnormalities. However, in the main trial, the rivaroxaban-based strategy was associated with a higher risk of death or thromboembolic complications and a higher risk of bleeding than the antiplatelet-based strategy.

DOI: 10.1056/NEJMoa1911426

Source: https://www.nejm.org/doi/full/10.1056/NEJMoa1911426