Predictors of left atrial thrombi for subsequent thromboembolisms: Risk factors derived from echocardiography

Evidence regarding the management of left atrial thrombi (LATs) is limited.

We aimed to investigate factors associated with subsequent thromboembolism in patients with LATs and explored potential management approaches.

This multicenter retrospective study consecutively enrolled patients who underwent morphological assessment of LAT using echocardiography. We evaluated associations between clinical and echocardiographic variables and the occurrence of symptomatic thromboembolism.

Two hundred six patients from 15 centers were enrolled. During follow-up period after echocardiographic diagnosis (651 days; interquartile range 174-1316 days), 19 patients (9.2%) developed thromboembolism. Cox regression analysis identified 3 independent predictors of thromboembolism: LAT maximum length > 20 mm (hazard ratio [HR] 2.63; 95% confidence interval [CI] 1.03-6.68; P=.043), reduced left ventricular ejection fraction (≤40%) (HR 2.95; 95% CI 1.14-7.63; P=.026), and thrombus mobility (HR 3.40; 95% CI 1.27-9.11; P=.015). Patients with ≥2 of these factors (52 [25.2%]) were categorized as the high-risk group, while those with <2 factors (154 [74.8%]) formed the low-risk group. Patients in the high-risk group had a higher incidence of thromboembolism (12 [23.1%] vs 7 [4.5%]; P<.001), despite a higher proportion undergoing urgent surgical thrombectomy (UST; 9 [17.3%] vs 9 [5.8%]; P=.025) compared with the low-risk group. In high-risk patients, UST was associated with a significantly lower rate of adverse outcomes, including all-cause mortality, heart failure hospitalizations, major bleeding, and thromboembolisms, at 90 days (0% vs 35.6%; log-rank, P=.048).

In patients with LATs, large thrombus size, reduced left ventricular ejection fraction, and thrombus mobility were associated with subsequent thromboembolism. UST was associated with fewer adverse clinical outcomes in patients with ≥2 risk factors.