In addition, the investigators will compare the incidence of postoperative nausea and vomiting (PONV) in both groups of patients after the procedure (globally and between the patients, who needed Transesophageal Echocardiography - TEE and not). In the case of PONV, Ondansetron (Zofran) will be ordered in the dose of 0.1mg/kg IV. If the PONV continues after ondansetron administration, the second dose of this drug will be given at the dose of 0.1 mg/kg.