We examined the relation between the echocardiographic morphology of cardiac myxoma and systemic embolism in 25 patients. Two distinct types of myxoma could be identified by echocardiography: round type characterized by solid and round shape with nonmobile surface (n = 13, 52%), and polypoid type characterized by soft and irregular shape with mobile surface (n = 12, 48%); multiple regression analysis revealed the polypoid type of tumor was the only independent predictor of systemic embolism (p = 0.0029).