[Significance of an upward shift of the ST segment during an exercise test]

The objective of this study is to investigate the significance of the occurrence of an upward shift of the ST segment curing a stress test in patients with no previous history of myocardial infarction. Over 10 years, totalling 9,500 stress tests, we have collected 10 cases. They always concern men including one with angina on exertion, one with spontaneous angina, one with spontaneous angina occurring at the end of an intense stress, and 7 with mixed angina. None of them had a previous history of myocardial infarction or documented spastic angina. The upward shift of the ST segment occurred 9 times during stress and once during recovery. 9 patients had a coronary arteriogram with in 8 cases severe fixed coronary lesions. The patient with the upward shift of ST during the recovery period had a normal coronary arteriogram with a positive methylergometrin test. There is a good correlation between the appearance of an upward shift of ST during stress in the anterior derivations and a significant involvement of the anterior interventricular artery. In our series, there were no complications, especially myocardial infarction, in the immediate period following the stress test. 7 patients underwent an aorto-coronary by-pass. The 10 patients are presently asymptomatic after a 47 months follow-up. The occurrence of an upward shift of ST during stress, in the absence of a previous history of myocardial infarction, represents in more than 80 p. cent of the cases the existence of severe coronary lesions leading to hospitalization and the immediate performance of a coronary arteriogram.(ABSTRACT TRUNCATED AT 250 WORDS)