Radioelectrocardiography during Exercise in Patients with the Anginal Syndrome Use of Multiple Leads

The electrocardiographic alterations during the period of and immediately following exercise were studied by means of radioelectrocardiography, in 90 patients with angina pectoris. Three leads (II, V 4 , and V 6 ) were utilized. The criteria for abnormality were based on the findings of 229 "normal" subjects between the ages of 17 and 39 and 300 "normal" subjects between the ages of 40 and 60. Sixty-eight of the 90 patients (76 per cent) with angina pectoris showed electrocardiographic abnormalities during and after the period of exercise. An additional seven patients (8 per cent) manifested alterations that were considered to be "probably abnormal." The incidence of false-negative tests was 10 per cent, those patients being excluded in whom the test had to be stopped early because of fatigue, leg pain, or other complaints. The findings indicate that the recording of the electrocardiogram during exercise adds considerably to the value of the test. In some patients (12 per cent), the electrocardiogram was positive only during the period of exercise, and in 30 per cent the abnormal findings were obtained chiefly during this period. The Master two-step test involves various technical and subjective difficulties such as interpretation of the alterations, wandering of the baseline, and lack of cooperation from the patient. In a certain percentage of patients with clinical angina pectoris false-negative tests are obtained. Also positive tests in subjects without definite anginal symptoms are not rare, but not enough long-term follow-up studies have been performed to delineate the significance of these findings. In spite of some limitations, the exercise electrocardiogram, especially that taken during as well as after exercise, is an important adjunct in the diagnosis of angina pectoris.