ventricle can be obtained to see wall motion in the basal, mid, and distal sections. If the probe is rotated clockwise, then the right heart and tricuspid valve can be visualized. It is in the transgastric position that is best used to quantify the aortic valve with pulse- and continuous-wave Doppler as this is the best view to be best coaxial with the valve. History The transesophageal echocardiogram was first invented by Dr. Leon Frazin in 1974 while working at the Loyola University Stritch School of Medicine, Maywood, and Veterans Administration Hospital, Hines, Illinois. His early findings were published in 1976 in Circulation Diseases While TEE can be used to answer many questions that a transthoracic echo can answer, the TEE is used for some diseases in particular. Infective endocarditis to get better quality images of the affected valve and better plan surgery, or need for surgery Aortic root abscess, which generally is not visible on transthoracic echo Eccentric mitral regurgitation can be better appreciated on TEE due to Coandă effect Left atrial appendage thrombus and evaluation, follow up, and insertion of a left atrial appendage occlusion device Evaluation for patent foramen ovale and atrial septal defect after a stroke, and insertion of a PFO/ASD plug Monitoring during a procedure to cross the interatrial septum safely without poking the needle through an undesired structure During cardiothoracic surgery for numerous procedures including immediately before and after replacement of a valve References External links Virtual TEE – online interactive learning resource TEE online simulator, interactive Cardiac imaging Medical ultrasonography