Blood pressure responses to stress: Relation to left ventricular structure and function

Abstract

The relations of resting blood pressure, blood pressure during standardized stressors, and workplace blood pressure to left ventricular structure and diastoKc filling were evaluated in 133 healthy young adults (mean age = 30 + 7 years) without hypertension. Each subject underwent the following." (a) measurement of basal blood pressure at the end of 15 minutes of rest; (b) measurement of blood pressure during a competitive reaction time task (a laboratory stressor which elicits a beta-adrenergically mediated increase in cardiac output); (c) measurement of blood pressure during a forehead compressor test, which results primarily in an increase in total peripheral resistance due to alpha-adrenergic stimulation; and (d) ambulatory blood pressure monitoring during a typical workday. Left ventricular structure (indexed left ventricular mass and relative wall thickness) and diastolic filling (peak filling velocity) were evaluated by echocardiography.All four measures of systolic blood pressure were significantly correlated with indexed left ventricular mass. The best predictor of indexed left ventricular mass was the systolic blood pressure during the compressor test (r = 0.32, p < O. 001), and this relation was significant after correcting for resting systolic blood pressure (p < 0.05). Relative wall thickness was most closely related to the average ambulatory workplace systolic pressure (r = 0.23, p < 0.01), and this relation was also independent of resting systolic blood pressure (p < 0.05). Peak filling velocity was inversely related to the systolic pressure in response to each stressor, but the correlations with stress-induced pressures were not significant after correcting for resting levels of blood pressure.These results demonstrate an association of structural characteristics of the left ventricle with blood pressure responses to stress.