Echocardiographic Equipment and Study Protocols
Transthoracic echocardiography was performed on all patients with use of the Vivid 7 system (GE-Vingmed Ultrasound AS, Horten, Norway), iE33 ultrasound system (Philips Medical Systems, Bothell, WA). Transesophageal echocardiography was performed with the use of iE33 ultrasound system (Philips Medical Systems, Bothell, WA). All patients were examined by routine 2-dimensional echocardiography. Color Doppler imaging was used to assess the occurrence of perforation and evaluate the function of the atrioventricular or semilunar valves.