Mental stress can provoke episodes of myocardial ischemia and may precipitate acute cardiac events in patients with coronary artery disease (CAD). Various studies have suggested that mental stress can trigger myocardial ischemia in 40 to 70 percent of patients with stable CAD. Identifying those who are at risk for mental stress–induced ischemia is difficult. Stone and colleagues considered the relationship between mental stress–induced myocardial ischemia and ischemia induced by daily activities or exercise. They also questioned whether patients at risk for mental stress–induced ischemia could be identified.

Patients with documented CAD with evidence of ischemia on treadmill stress tests were included in the study. Patients were evaluated with 48-hour ambulatory electrocardiography (ECG) to evaluate ischemic episodes. Two tests, a speech test and a color-word match test, measured mental stress. The patients' heart rate and blood pressure were measured, along with neurohormone levels, before, during and after these tests.

Over one half of the 196 patients enrolled in the study developed ischemia during one or both of the mental stress tests. Those who developed mental stress–induced ischemia on the speech test were much more likely to have daily ischemia on the ambulatory monitor. There was no difference between patients with and patients without mental stress–induced ischemia during the treadmill stress tests.

Patients with mental stress-induced ischemia had more episodes of ischemia during daily activity. These patients appear to have a more exaggerated hemodynamic response to mental stress. The predictor for patients at risk for mental stress–induced ischemia was the result of 48-hour ambulatory ECG monitoring. The authors conclude that patients with daily myocardial ischemia have a heightened response to mental stress. Management strategies in these patients should focus on behavior modification and pharmacologic treatment aimed at preventing excessive physiologic response to mental stress.