This study presents the initial experience of our department with transesophageal echocardiography. Transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE) were performed simultaneously in 31 clinical patients (16 to 76 years old). 13 pts with aortic (9) and mitral (4) valve disease, 10 pts with ischemic heart disease (including 7 AMI), 3 pts with congestive cardiomyopathy, 2 pts with aortic aneurysm and 3 pts with other heart diseases. The investigations were performed with use of Aloka SSD 650 machine and 7.5 MHz transesophageal convex transducer. The patients were prepared for the examination in the typical way by local anesthesia, administration of sedatives and heart monitoring. The following projections were used: basic short- and long-axis view, four chamber view, and transgastric view. These investigation confirmed the usefulness TEE for evaluation of aortic and mitral valves, especially their morphology, atrial septum and atrial cavities. Contractility and other heart structures were difficult to be evaluated by TEE. It seems to be possible to estimate the proximal sections of the coronary arteries. Only few complications were found: supraventricular (2) and ventricular extrasystoles (8), transient supraventricular tachycardia (3), and bradycardia (3). Late complications were not found.