- Backgound: The use of intraoperative transesophageal echocardiogram in patients with infective endocarditis is usually reserved for cases of inadequate preoperative testing or suspected extension to perivalvular tissue. Objectives: To explore the impact of routine intraoperative TEE in patients with infective endocarditis. Methods: The impact of intraoperative TEE on the operative plan, anatomic-physiologic results, and hemodynamic assessment or de-airing was analyzed in 59 patients (38 males, 21 females, mean age 57.7 ± 16.8 years, range 20–82) operated for active infective endocarditis over 56 months. Results: Immediate pre-pump echocardiography was available in 52 operations (86.7%), and changed the operative plan in 6 of them (11.5%). Immediate post-pump study was available in 59 patients (98.3%) and accounted for second pump-run in 6 (10.2%): perivalvular leak (3 cases), and immobilized leaflet, significant mitral regurgitation following vegetectomy, and failing right ventricle requiring addition of vein graft (1 case each). Prolonged de-airing was necessary in 6 patients (10.2%). In 5 patients (8.5%) the postoperative study aided in the evaluation and treatment of difficult weaning from the cardiopulmonary bypass pump. In 21 patients (35.6%) the application of intraoperative TEE affected at least one of the four pre-specified parameters. Conclusions: Intraoperative TEE has an important role in surgery for infective endocarditis and should be routinely implemented.