Effect of mental stress on hemodynamics and left ventricular diastolic function in patients with ischemic heart disease

Abstract

Mental stress is an important factor affecting cardiac function. We evaluated the effect of a mental calculation stress (MS) test on hemodynamics and left ventricular (LV) diastolic function in patients with ischemic heart disease, and compared the hemodynamic responses with a treadmill exercise test. Fifteen patients were studied. Seven had old myocardial infarction with significant coronary artery stenosis (group I) and 8 had chest pain syndrome with non-significant coronary artery stenosis (group II). The MS test was performed as follows: after memorizing 6 random numeral digits, patients repeated these numbers in reverse order for 5 rain followed by serial subtraction of 1000 minus 17 for 5 min. Blood pressure (BP) and heart rate (HR) were measured every 1-5 min. Doppler mitral flow velocity (MFV) was recorded every 2-5 min. During the MS test, BP, HR, and rate pressure product increased by 38.3%, 17.3%, and 62.1% on average, respectively. Early diastolic MFV decreased by 10.0% in group I and 3.3% in group II. First third filling rate of MFV decreased by 32.3% in group I and 22.8% in group II. A/E ratio increased by 39.3% in group I and 25.8% in group II. These data indicate that the MS test led to a deterioration in LV diastolic function. The MS test induced LV diastolic dysfunction to a greater extent in patients with significant coronary artery stenosis than in those without significant coronary stenosis. Myocardial ischemia may be induced by increased left ventricular afterload and/or vasoconstrictive reflex of coronary microcirculation.