Psychological determinants of anginal pain perception during exercise testing of stable patients after recovery from acute myocardial infarction or unstable angina pectoris.

The objective of this study was to test the hypothesis that psychological factors are determinants of anginal symptoms during positive exercise tests. The sample consisted of clinically stable patients who were enrolled in the Multicenter Study of Myocardial Ischemia 1 to 6 months after admission to a coronary care unit. Among 186 post-myocardial infarction patients, 151 developed ischemia (i.e., a stress-induced myocardial perfusion defect) without symptoms (silent ischemia) and 35 developed angina with ischemia (symptomatic ischemia) during a thallium exercise test; among 39 patients who had been hospitalized for unstable angina, 24 developed silent ischemia and 15 developed symptomatic ischemia. Two sets of psychometric tests were administered: set 1, factors that influence awareness of physical symptoms, and set 2, factors associated with biases toward or against reporting perceived symptoms. Two hundred eleven patients produced complete data in each set. Analysis of set 1 factor scores revealed significant effects of symptom status (p = 0.006) and index event (p = 0.02), but no interaction. No effects were found in set 2. Patients who are clinically stable after recovery from an acute coronary event and who experience angina during exercise testing are more aware of physical symptoms in general than are comparable patients with silent ischemia. Psychological biases toward or against reporting perceived symptoms do not differentiate these groups. Thus, it appears that silent ischemia is probably "silent" in the sense of being truly asymptomatic rather than of stoic endurance or denial of perceived symptoms.