From the Departments of Radiology (W.Y., G.R., X.Z., L.W., H.L.), Cardiovascular Surgery (X.J.), and Adult Echocardiography (O.C., Q.M., H.F., Q.L.), Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, No. 106 Zhongshan 2nd Road, Guangzhou, Guangdong, P. R. China 510080.