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Mental stress as an acute trigger of ischemic left ventricular dysfunction and blood pressure elevation in coronary
C N Bairey1, D S Krantz, A Rozanski
1University of California, Los Angeles School of Medicine.
Insights
Mental stress can trigger heart problems like ischemia and heart attacks. This study found that mental stress causes significant blood pressure increases and heart abnormalities in patients with existing coronary artery disease.
Area of Science:
- Cardiology
- Psychophysiology
- Medical Imaging
Background:
- Acute mental stress is a known trigger for cardiac events, including myocardial infarction and sudden cardiac death.
- The precise mechanisms linking mental stress to cardiac ischemia are not fully understood.
- Previous research suggests a correlation between psychological stress and cardiovascular events.
Purpose of the Study:
- To investigate the effects of mental stress on hemodynamics and left ventricular wall motion abnormalities in patients with exercise-induced myocardial ischemia.
- To compare the physiological responses to mental stress versus physical exercise in this patient group.
- To explore the potential role of mental stress-induced blood pressure elevation in the pathophysiology of acute ischemic coronary events.
Main Methods:
- Radionuclide ventriculography was used to assess left ventricular wall motion abnormalities in 29 patients with exercise-induced myocardial ischemia.
- Hemodynamic parameters, including peak systolic arterial pressure, were measured during both mental stress and exercise protocols.
- Ambulatory radionuclide detection was considered for enhanced monitoring of cardiac function and ischemia.
Main Results:
- Seventy-five percent of patients exhibited mental stress-induced wall motion abnormalities.
- Mental stress led to greater increases in peak systolic arterial pressure compared to exercise in many patients.
- Personally relevant mental stress was most potent in inducing ischemia, often occurring silently at lower heart rates than exercise-induced ischemia.
- Increased blood pressure during mental stress-induced ischemia suggests a role for elevated myocardial oxygen demand.
Conclusions:
- Mental stress can induce significant hemodynamic changes and left ventricular dysfunction in patients with coronary artery disease.
- The findings provide a pathophysiological link between mental stress and acute ischemic coronary events, potentially involving atherosclerotic plaque rupture.
- Ambulatory monitoring technologies may improve the detection and management of transient myocardial ischemia triggered by mental stress.
Abstract:
Acute mental stress may be a frequent trigger of transient myocardial ischemia, myocardial infarction and sudden cardiac death. In an experimental setting, the effect of mental stress on hemodynamics and left ventricular wall motion abnormalities (as detected by radionuclide ventriculography) was measured in 29 patients with exercise-induced myocardial ischemia. Seventy-five percent of the patients demonstrated mental stress-induced wall motion abnormalities. Patients frequently exhibited greater increases in peak systolic arterial pressure during mental stress than during exercise. Personally relevant mental stress is the most potent type of mental stress, both in terms of frequency and magnitude of ischemia. Most mental stress-induced ischemic episodes are clinically and electrocardiographically silent and occur at heart rates significantly lower than those seen during exercise. Both systolic and diastolic blood pressure increased during mental stress-induced ischemia, suggesting that increased myocardial oxygen demand plays a role in the pathophysiology of mental stress-induced transient ischemia. The significant magnitude and acute onset of this mental stress-induced blood pressure elevation may in some manner contribute to atherosclerotic plaque rupture. These findings may provide a pathophysiologic link to the epidemiologic association between mental stress and acute ischemic coronary events. A new ambulatory radionuclide detector that can concurrently monitor left ventricular ejection fraction and electrocardiographic ST-segment change may enhance the detection and evaluation of transient myocardial ischemia in ambulatory coronary patients.