Mental Stress and Myocardial Ischemia

The purpose of this study was to determine whether mental stress played a significant role in myocardial ischemia. 45 patients were taken for mathematical mental stress testing (MST), exercise treadmill testing (ET) and coronary angiography. Subsequently, we identifed 34 patients with a critical coronary lesion angiography (group I) and compared them with 11 patients with normal coronary angiograms (group II). Six patients in group I had transient ischemic changes on ECG on MST. In contrast, no ECG changes were observed in group II. While the sensitivity and specificity of MST were 17.6 % and 100%, respectively, the sensitivity and specificity of ET were 73.5 % and 90.9, respectively. It was observed that MST increased the heart rate (HR), systolic blood pressure (SBP) and the rate-pressure product (DP) in a significant manner. With MST, the HR increased from 81.3±13.7 beats per minute (bpm) to 99.6±15.8 in group 1 (p<0.01) and from 84±14.1 to 101.1±20.2 (p<0.01) in group II, while SBP increased from 137.5±20.4 mmHg to 161.8±24.9 in group I 5p<0.01) and from 140.1±14.6 to 168.7±22.6 in group II (p<0.01). Furthermore, the DP increased from 11.063±4.921 mmHgxbpm to 15.563±4.184 in group I (p<0.01) and from 10.954±4.872 to 16.09±4.685 in group II (p<0.01). The increases in HR, SBP, and DP were more marked with ET in both groups. Finally, the value for the DP obtained from ET (28.244±5.583 mmHgxbpm) was found to be higher than that of MST (15.692±5.341) (p<0.005). Our data confirmed that mental stress causes myocardial ischemia by increasing the HR and SBP. However, unlike ET, MST has not been recommended as a screening test in establishing the diagnosis of myocardial ischemia.