Background: Ischemia during laboratory mental stress tests has been linked to significantly higher rates of adverse cardiac events. Previous studies have not been designed to detect differences in mortality rates.
Methods and results: To determine whether mental stress-induced ischemia predicts death, we evaluated 196 patients from the Psychophysiological Investigations of Myocardial Ischemia (PIMI) study who had documented coronary artery disease and exercise-induced ischemia. Participants underwent bicycle exercise and psychological stress testing with radionuclide imaging. Cardiac function data and psychological test results were collected. Vital status was ascertained by telephone and by querying Social Security records 3.5+/-0.4 years and 5.2+/-0.4 years later. Of the 17 participants who had died, new or worsened wall motion abnormalities during the speech test were present in 40% compared with 19% of survivors (P=0.04) and significantly predicted death (rate ratio=3.0; 95% CI, 1.04 to 8.36; P=0.04). Ejection fraction changes during the speech test were similar in patients who died and in survivors (P=0.9) and did not predict death even after adjusting for resting ejection fraction (P=0.63), which was similar in both groups (mean, 56.4 versus 59.7; P=0.24). Other indicators of ischemia during the speech test (ST-segment depression, chest pain) did not predict death, nor did psychological traits, hemodynamic responses to the speech test, or markers of the presence and severity of ischemia during daily life and exercise.
Conclusions: In patients with coronary artery disease and exercise-induced ischemia, the presence of mental stress-induced ischemia predicts subsequent death.