Left Atrial Thrombus and Dense Spontaneous Contrast in Direct Oral Anticoagulant Therapy of Atrial Fibrillation: Insights from a Reference Center

Abstract Background In the treatment of atrial fibrillation (AF), the most frequently sustained arrhythmia, with catheter ablation (CA) or electrical cardioversion (ECV), the periprocedural period is one of the most critical phases. Currently, the use of new direct action oral anticoagulants (DOAC) is increasingly frequent; however, in the real world, there are still few data on studies on the thrombus incidence in the left atrium (TrLA) or dense spontaneous contrast (DSC) on transesophageal echocardiogram (TEE). Objective To evaluate the prevalence of events and association with risk factors in patients using DOACs. Primary objective: to analyze the prevalence of thrombus in the LA by TEE in patients using DOAC undergoing ECV/CA. Second, evaluate the association of comorbidities with the presence of thrombi and DSC. Methods Retrospective cohort, single-center study with patients followed at the Arrhythmia Outpatient Unit (InCor-HCFMUSP). Patients indicated for procedures and using DOACs were selected, and their clinical/echocardiographic data were analyzed. A significance level of 5% was considered. Results 354 patients were included, a total of 400 procedures, from March 2012-March 2018. Thrombus in the LA was found in 11 patients (2.8%), associated with advanced age (p=0.007) and higher CHA2DS2-VASc (p<0.001) score. DSC in the LA before TEE was found in 29 patients (7.3%), with lower LVEF (p<0.038) and greater LA dimension (p<0.0001). Conclusion The incidence of LA thrombus and DSC in patients using DOC in the context of AF ECV/CA, although small, is not negligible. Patients with higher CHA2DS2-VASc scores, especially older and with larger LA diameter, are more prone to these echocardiographic findings.

摘要 背景 心房颤动（AF）是最常见的持续性心律失常，在采用导管消融（CA）或电复律（ECV）治疗该疾病时，围手术期是最为关键的阶段之一。目前，新型直接口服抗凝药（DOAC）的应用日益广泛；但在真实世界中，关于经食管超声心动图（TEE）下左心房血栓（TrLA）或致密自发显影（DSC）发生率的研究数据仍较为匮乏。
目的 评估使用直接口服抗凝药（DOAC）患者的相关事件发生率及其与危险因素的相关性。首要研究目标：分析拟行电复律（ECV）或导管消融（CA）且使用DOAC的患者中，经TEE检出的左心房血栓患病率。次要研究目标：评估合并症与左心房血栓及DSC存在的相关性。
方法 本研究为单中心回顾性队列研究，研究对象为在心律失常门诊（InCor-HCFMUSP）随访的患者。筛选拟行相关手术且使用DOAC的患者，对其临床及超声心动图数据进行分析，检验水准设定为5%。
结果 本研究共纳入354例患者，涵盖2012年3月至2018年3月期间的400例次手术。其中11例患者（2.8%）检出左心房血栓，其与高龄（p=0.007）及较高的CHA₂DS₂-VASc评分（p<0.001）显著相关。29例患者（7.3%）在TEE检查前检出左心房DSC，该表现与较低的左心室射血分数（LVEF，p<0.038）及更大的左心房内径（p<0.0001）相关。
结论 在心房颤动患者行ECV/CA且使用DOAC的背景下，左心房血栓及DSC的发生率虽较低，但仍不可忽视。CHA₂DS₂-VASc评分较高的患者，尤其是高龄及左心房内径更大的患者，更易出现上述超声心动图表现。