Exaggerated reactivity to mental stress is associated with exercise- induced myocardial ischemia in an asymptomatic high-risk population

Background: This study was done to determine whether cardiovascular reactivity to mental stress is associated with exercise-induced occult ischemia in an asymptomatic population at high risk for premature coronary heart disease (CHD). Methods and Results: One hundred fifty-two siblings of persons with premature CHD underwent mental stress testing. Exercise thallium tomography and 24-hour Holter monitoring were also performed. Hemodynamic changes were monitored during both stressors. Siblings positive for exercise- induced ischemia were offered cardiac catheterization. During mental stress, siblings with an abnormal exercise ECG and/or thallium scan (n=15) had greater maximal increases in systolic blood pressure (SBP, P=.0004) and diastolic blood pressure (DBP, P=.05) and had greater heart rate variability in the normalized low frequency domain of an analysis of Holter monitor recordings, compared with siblings without exercise-induced ischemia. Coronary arteriography confirmed coronary atherosclerosis in 85% of siblings with exercise-induced ischemia. Regression analyses showed that occult ischemia during exercise was a strong independent predictor of maximal change in SBP and DBP during mental stress. A multivariate logistic model demonstrated that siblings with exercise-induced occult ischemia were 21 times more likely to be 'hot' responders (top quartile of change in SBP and DBP) during mental stress. Conclusions: An exaggerated cardiovascular response to mental stress is associated with exercise-induced myocardial ischemia in persons with preclinical coronary heart disease.