Department of Cardiology, Fujita Health University.
Department of Joint Research Laboratory of Clinical Medicine, Fujita Health University Hospital.
Circ J. 2018 Oct 25;82(11):2715-2721. doi: 10.1253/circj.CJ-18-0398. Epub 2018 Aug 11.
In atrial fibrillation (AF) patients, the effect of direct oral anticoagulant (DOACs) therapy on the incidence of left atrial appendage thrombus (LAT) remains poorly investigated. This study examined the prevalence and risk factors of LAT in AF patients on DOACs undergoing catheter ablation, and sought an anticoagulation strategy for LAT.
In 407 AF patients on DOACs, transesophageal echocardiography (TEE) was performed 1 day before ablation. If patients had LAT, initial DOACs were switched to dabigatran (300 mg) or warfarin based on their renal function; TEE was repeated after treatment for ≥4 weeks. LAT was detected in 18 patients (4.4%). The prevalence of persistent AF and low-dose treatment/inappropriate dose reduction of DOACs, CHADS/CHADS-VASc scores, serum N-terminal pro-brain natriuretic peptide levels, and LA dimension/LA volume index significantly increased in patients with LAT vs. those without LAT. AF rhythm on TEE and spontaneous echo contrast also increased in patients with LAT; LA appendage flow velocity decreased. In the multivariate analysis, persistent AF and inappropriately reduced DOAC dose were risk factors for LAT. On repeat TEE, LAT had disappeared in 13 of 16 patients treated with dabigatran and in 2 of 2 patients treated with warfarin.
DOACs still carry a finite risk of LAT in AF patients. Inappropriately reduced DOAC dose should be avoided to minimize the thromboembolic risk. Regular-dose dabigatran may have therapeutic efficacy against LAT.
在心房颤动（AF）患者中，直接口服抗凝剂（DOAC）治疗对左心耳血栓（LAT）发生率的影响仍研究甚少。本研究检测了正在接受导管消融治疗的 AF 患者中 DOAC 治疗时 LAT 的发生率和危险因素，并寻找 LAT 的抗凝策略。
在 407 例接受 DOAC 治疗的 AF 患者中，在消融前 1 天行经食管超声心动图（TEE）检查。如果患者存在 LAT，则根据肾功能将初始 DOAC 转换为达比加群（300 mg）或华法林；治疗≥4 周后重复 TEE。在 18 例患者（4.4%）中发现 LAT。与无 LAT 患者相比，持续性 AF 以及 DOAC 低剂量治疗/剂量不当减少、CHA2DS2-VASc 评分、血清 N 末端脑钠肽前体水平和左心房（LA）直径/LA 容积指数在 LAT 患者中显著增加。LAT 患者 TEE 上的 AF 节律和自发性回声对比也增加，LA 心耳血流速度降低。在多变量分析中，持续性 AF 和 DOAC 剂量不当减少是 LAT 的危险因素。在重复 TEE 检查中，16 例接受达比加群治疗的患者中有 13 例和 2 例接受华法林治疗的患者中 LAT 消失。
DOAC 治疗仍会给 AF 患者带来有限的 LAT 风险。应避免 DOAC 剂量不当减少，以最大程度降低血栓栓塞风险。常规剂量的达比加群可能对 LAT 有治疗作用。
