Relation Between Exercise Central Hemodynamic Load and Resting Cardiac Structure and Function in Young Men

Abstract

Left ventricular (LV) structure and function are predictors of cardiovascular mortality and related to resting peripheral hemodynamic load in older adults. The central hemodynamic response to exercise may reveal associations with LV structure and function not detected by traditional peripheral (brachial) measures in a younger population. PURPOSE: Examine correlations between acute exercise-induced changes in brachial blood pressure (BP), arterial stiffness and wave reflections and measures of resting LV structure and function. METHODS: 16 healthy men (age 26 ± 6 yr; BMI 25.3 ± 2.7 kg·m-2) had measures of central hemodynamic load measured pre/post a 30 second Wingate anaerobic test (WAT). Brachial systolic BP and carotid systolic BP were assessed using an automated cuff and applanation tonometry, respectively. Carotid artery stiffness and reflected wave intensity were assessed as the elastic modulus (Ep) and negative area (NA) from Doppler-ultrasound and wave intensity analysis. Resting LV structure (LV mass) and function (fractional shortening, FS) were assessed using M-mode echocardiography in the parasternal short-axis view. RESULTS: There were significant inverse associations between resting FS and WAT-induced increase in: carotid systolic BP (r = -0.54, p = 0.04), logNA (r = -0.53, p = 0.02) and Ep (r = -0.45, p = 0.04). There were no significant associations between resting FS and increases in brachial systolic BP (r = -0.38, p > 0.05) or between resting LV mass and increases in any hemodynamic variable (p > 0.05). CONCLUSION: Exercise-induced increases in central hemodynamic load reveal associations with resting LV function undetected by traditional peripheral hemodynamics. Changes in LV function may precede changes in LV structure offering insight into lack of associations between central hemodynamic load and LV mass in young healthy men.