Abstract 12707: Chads2 and Chads2vasc Scores Predict the Risk for Left Atrial Thrombus in Patients With Atrial Fibrillation

Background: The study was to evaluate the value of CHADS2 and CHADS2VASC scores on predicting left atrial (LA) thrombus in the patients with atrial fibrillation (AF). Methods and Results: All the non-valvular AF patients undergoing AF ablation from June 2010 to June 2012 were included and divided into two groups: patients without anticoagulation and with Coumadin anticoagulation for at least 4 weeks. The relationship between CHADS2 and CHADS2VASC scores and LA thrombus as identified on transesophageal echocardiography (TEE) was analyzed prior to ablation. A total of 397 patients underwent pre-ablation TEE: 212 patients without anticoagulation, and 185 with anticoagulation. There were no differences in the CHADS2 and CHADS2VASC scores in the two groups. LA thrombus was present in 15.6% and 5.9% for the patients without anticoagulation and for those with anticoagulation, respectively (p = 0.002). There was a strong association between CHADS2 and LA thrombus, and between CHADS2VASC and LA thrombus in the two groups. No thrombus was identified in patients with CHADS2VASC score of 0 in both groups. However, thrombus was detected in 3.5% of patients with CHADS2 score of 0 in the group without anticoagulation, while no thrombus was present in the ones with anticoagulation. CHADS2VASC score of ≥1 (r=2.03, p = 0.04) was the only factor independently associated with LA thrombus in patients without anticoagulation, while both CHADS2VASC score of ≥2 (r=2.61, p=0.02) and CHADS2 score of ≥2 (r=2.73, p=0.01) were independently associated with LA thrombus. Further analyses showed that CHADS2VASC score was a better predictor for LA thrombus than CHADS2 score in patients without anticoagulation. However, there was no difference between the two scoring systems in predicting LA thrombus in patients with anticoagulation. Conclusions: LA thrombus was associated with CHADS2VASC and CHADS2 scores in non-valvular AF patients without anticoagulation. CHADS2VASC score was a better predictor than CHADS2 score for LA thrombus in patients without anticoagulation. The data suggested that it might be unnecessary to undergo a TEE evaluation for LA thrombus in low risk patients identified by CHADS2VASC score regardless anticoagulation therapy prior to cardioversion or ablation.