Angina Score Analysis Based on Clinical Findings and on the Results of Stress-Echocardiography Exercise Test in Patients With Silent Myocardial Ischemia

Introduction. Stress echocardiography is an important method for detecting silent myocardial ischemia. Aim of the study was to analyze the exercise test results in silent ischemia and ordinary angina (control group) and compare angina scores based on exercise tests or clinical findings. Materials and Methods. Data of 202 patients were analyzed. Stress tests were performed using a treadmill. The statistics included parametric t-test criterion for normally distributed samples and nonparametric Mann-Whitney and Fisher criteria for the other ones. Differences were considered significant at p<0.05. Results and Discussion. According to exercise tests in patients with ST depression, the angina scores were higher in the control group (M=2.1) than in the silent ischemia group (M=1.03, p=0.000001). Angina scores based on clinical findings did not differ between the groups. Among patients with decrease in contractility in exercise test, angina scores were higher in the control group (M=2.29) than in the silent ischemia group (M=1.36, p=0.000001). In the silent ischemia group, angina scores based on exercise tests were higher (p=0.015) than those based on clinical findings. In the control group, angina scores based on exercise tests were lower (p=0.0003) than those based on clinical findings. In the silent ischemia group, ventricular extrasystole occurred in exercise tests less frequently than in the control group (p=0.04). Conclusions. In exercise tests with ST depression, in the silent ischemia group, angina scores based on exercise tests coincide with those based on clinical findings; in the control group, angina scores based on exercise test are lower than those based on clinical findings. In exercise test with a decrease in segmental contractility, in the silent ischemia group, angina scores based on exercise tests are higher than those based on clinical findings; in the control group, angina scores based on exercise tests are lower than those based on clinical findings. Maximum ST depression is greater in the silent ischemia group than in control one, which indicates a pronounced myocardial ischemia in the silent ischemia group on exercise. Ventricular extrasystole occurred less frequently in the silent ischemia group than in the control group on exercise test with ST depression or with a decrease in segmental contractility. In silent myocardial ischemia patients, their myocardium tolerates exercise tests worse than that of the patients in the control group, which may be a typical characteristic of silent ischemia myocardium.