[Transesophageal echocardiography in combination with atrial stimulation for detection of ischemia-induced disorders of myocardial wall motion].

The diagnostic value of exercise echocardiography has been widely reported. In up to 20% of patients conventional transthoracic exercise echocardiography however is impossible due to impaired image quality related to exercise. In addition some patients will not be able to perform a conventional bicycle exercise test due to joint disease or peripheral vascular disease or a sufficient stress is not possible because of lack of patient motivation. In an attempt to overcome these limitations, a system has been developed which combines transesophageal echocardiography with simultaneous transesophageal atrial pacing via the same probe. Three circular silver pacing electrodes were installed at a distance of 7,9 and 12 cm from the tip of the echoscope. Square wave pulses of 10 ms and an intensity of 7 to 20 mA were delivered. After baseline recording at the patient's spontaneous heart rate, atrial pacing was initiated at a rate of 100 beats/min and increased stepwise every 2 min by 20 beats/min up to 85% of the age-predicted maximal heart rate. Pacing endpoints were designated to be the development of angina pectoris or dyspnea, persisting horizontal or downsloping ST-segment depression (0.2 mV 80 ms after the J-point in the 12-lead ECG) or the development of new segmental wall motion abnormalities. In a group of 50 patients with suspected coronary artery disease, coronary artery disease (luminal narrowing of more than 70% of at least one major vessel) was detected with high sensitivity (greater than 93%) and specificity (greater than 100%).(ABSTRACT TRUNCATED AT 250 WORDS)