ECG-CHANGES DURING TRANSESOPHAGEAL ECHOCARDIOGRAPHY IN PATIENTS WITH CORONARY HEART-DISEASE

There is only little knowledge about ECG-changes during transesophageal echocardiography in patients suffering from coronary heart disease. In 30 patients with a history of angina on exercise (n = 29) or angina at rest (n = 13) which were admitted to the cardiology department for further diagnostic procedures (group I) we analyzed ECG-changes during transesophageal echocardiography. Coronary heart disease was documented by exercise-ECG, dipyridamole test and coronary arteriography. 8 volunteers without coronary heart disease were studied in the control group (group II). All patients had no ischemic signs during ECG at rest prior to the transesophageal investigation. Blood pressure was measured before and immediately after the insertion of the esophageal probe. ECG was registered before and continuously during the transesophageal investigation. Concerning the sensitivity for ST-segment depression during transesophageal echocardiography the following data were calculated in relation to: exercise-ECG: 100%, dipyridamole test: 83%, and coronary angiography: 92%. The data for specificity were calculated with 50, 75 and 100%. Most of the patients with pathologic angiograms showed relevant ST-segment depression during exercise-ECG (72.2%), dipyridamole test (94.4%) and transesophageal echocardiography (88.8%). Only one patient suffered from angina pectoris during the transesophageal procedure. In the control group neither ST-segment depression nor angina pectoris were found. In group I we found an increase of heart rate of 40% (p < 0.0001) and of systolic blood pressure of 7% (p < 0.005). In group II similar data were found which were also statistically significant. Thus, doing transesophageal echocardiography in patients with coronary heart disease one has to be aware of ST-segment depression. These ECG-changes could be indicators for episodes of silent myocardial ischemia.