Transient left ventricular dysfunction during provocative mental stress in patients with coronary artery disease

We studied the temporal effects of various types of mental stress and physical exercise on the left ventricular ejection fraction (LVEF)in seven normal volunteers and nine patients with coronary artery disease. Three types of psychological stress were administered: mental arithmetic, the Stroop color word test, and a personally relevant speaking task. In the normal volunteers the LVEF response was either flat or increased (p < 0.05) compared to the baseline value during the mental tasks and increased by a mean of 10 ± 5% (p < 0.05) during exercise. In contrast, in patients with coronary disease in whom LVEF did not increase ≥ 5% during exercise, LVEF decreased significantly during the mental tasks (p < 0.05 for arithmetic and Stroop tasks). Typically LVEF decreased quickly during mental stress with an immediate rebound after intervention. Decreases in LVEF during mental stress occurred without chest pain and were not associated with ECG changes. In patients with coronary disease in whom LVEF increased normally with exercise (LVEF increase ≥ 5%), no significant changes in LVEF occurred during mental stress. The heart rate × systolic blood pressure double product during mental stress was significantly less than that achieved during exercise (p < 0.05) in each normal subject and patient. Thus psychological stress can provoke acute decreases in LVEF in patients with coronary disease and exercise-inducible dysfunction. The silent nature of the mental stress-induced abnormalities and their occurrence at a lower physiologic workload compared to abnormalities during exercise parallel characteristics of transient ischemia noted during ambulatory monitoring. Our results show the usefulness of serial left ventricular function monitoring for studying the pathophysiology of silent myocardial ischemia.