Is CHA2DS2-VASc score a predictor of left atrial thrombus in patients with paroxysmal atrial fibrillation? - Tang, Ri-Bo; Dong, Jian-Zeng; Liu, Xing-Peng; Long, De-Yong; Yu, Rong-Hui; Du, Xin; Liu, Xiao-Hui; Ma, Chang-Sheng (Thrombosis and Haemostasis, 2011)