Conclusions
The cardiac blood cyst is a rare benign primary tumor of the heart. The difference in location can cause different hemodynamic effects. Small blood cyst which causes no hemodynamic effects do not require any treatment and only requires regularly followed up. When the hemodynamic changes are caused, the operation can be performed and the prognosis is good. Transthoracic and transesophageal echocardiography can increase the diagnostic accuracy and transesophageal echocardiography is sensitive to small cyst less than 5mm. To manage the echocardiography characteristics of the cardiac blood cyst, it is helpful by doing early detection, diagnosis, and clinical treatment.