Assessing thromboembolic risk is crucial for proper management of patients with atrial fibrillation. Left atrial volume is a promising predictor of cardiac thrombosis. To determine whether left atrial volume can predict left atrial appendage thrombus in patients with atrial fibrillation, we conducted a prospective study of 73 patients. Left atrial and ventricular volumes were evaluated by cardiac computed tomography with retrospective electrocardiographic gating and then indexed to body surface area. Left atrial appendage thrombus was confirmed or excluded by cardiac computed tomography with delayed enhancement.

Seven patients (9.6%) had left atrial appendage thrombus; 66 (90.4%) did not. Those with thrombus had a significantly higher mean left atrial end-systolic volume index (139 ± 55 vs 101 ± 35 mL/m²; P =0.0097) and mean left atrial end-diastolic volume index (122 ± 45 vs 84 ± 34 mL/m²; P =0.0077). On multivariate logistic regression analysis, left atrial end-systolic volume index (per 10 mL/m² increase) was significantly associated with left atrial appendage thrombus (odds ratio [OR]=1.24; 95% CI, 1.03–1.50; P =0.02); so too was the left atrial end-diastolic volume index (per 10 mL/m² increase) (OR=1.29; 95% CI, 1.05–1.60; P =0.02).

These findings suggest that increased left atrial volume increases the risk of left atrial appendage thrombus. Therefore, patients with atrial fibrillation and an enlarged left atrium should be considered for cardiac computed tomography with delayed enhancement to confirm whether thrombus is present.

评估血栓栓塞风险对于正确管理房颤患者至关重要。左心房容积是心脏血栓形成的有希望的预测指标。为了确定左心房容积是否可以预测心房颤动患者的左心耳血栓，我们对 73 名患者进行了前瞻性研究。左心房和心室容积通过心脏计算机断层扫描与回顾性心电图门控进行评估，然后根据体表面积进行索引。通过延迟增强的心脏计算机断层扫描证实或排除左心耳血栓。

7 名患者 (9.6%) 有左心耳血栓；66 (90.4%) 没有。血栓患者的平均左心房收缩末期容积指数（139 ± 55 vs 101 ± 35 mL/m ²；P  = 0.0097）和平均左心房舒张末期容积指数（122 ± 45 vs 84 ± 34 mL /m ²；P  = 0.0077)。在多变量逻辑回归分析中，左心房收缩末期容积指数（每增加10 mL/m ²）与左心耳血栓显着相关（优势比 [OR]=1.24；95% CI，1.03–1.50；P  =0.02 ); 左心房舒张末期容积指数（每增加10 mL/m ²）也是如此（OR=1.29；95% CI，1.05–1.60；P  =0.02）。

这些发现表明左心房容积增加会增加左心耳血栓的风险。因此，房颤和左心房扩大的患者应考虑进行延迟增强的心脏计算机断层扫描，以确认是否存在血栓。