The extent of preoperative TEE
TEE was performed using the Philips iE33 or the GE Vivid S 70 ultrasound machine equipped with X7-2t Live 3D or 6VT-D probes. Images were obtained before the procedure, after general anesthesia and tracheal intubation, during preparation of the surgical field and dissection and stabilization of the leads in the device pocket. Leads were evaluated in the mid-esophageal, inferior esophageal and modified transgastric views to visualize the right ventricle and the tricuspid valve. In order to obtain complete visualization of the structures (and assessment of lead/heart interaction) non-standard imaging planes were sometimes required. After the procedure the results were entered into a computer database. We analyzed the number, location and course of the leads: in the superior vena cava (SVC), right atrium (RA), right ventricle (RV) (taking into account excess lead loops). We also assessed lead mobility, presence of sites at which the lead was bound to cardiac structures, lead-to-lead binding sites and additional masses attached to the leads. An important part of the imaging protocol was assessment of the effect of the lead on tricuspid function. Additionally, we assessed left ventricular function (LVEF), pericardial function and possible presence of structural heart disease (atrial or ventricular septal defects).