Menopause influences aortic pulse pressure and pressure wave responses to metaboreflex activation in women

Abstract

ObjectivePostmenopausal women (post-MW) have greater risk of heart failure due to aortic pulsatile overload on the left ventricle associated with increased backward wave pressure (Pb). Post-MW have exaggerated peripheral blood pressure (BP) response to exercise mediated by metaboreflex (postexercise muscle ischemia [PEMI]) overactivation. Increased forward wave pressure (Pf) and Pb are determinants of aortic pulse pressure (PP) during isometric handgrip exercis (IHG) in young adults. We hypothesized that aortic PP and pressure wave responses to PEMI are augmented in nonhypertensive post-MW compared with premenopausal women (pre-MW).MethodsAortic BP, Pf, Pb, and reflection magnitude were assessed at rest and during IHG and PEMI by applanation tonometry in 15 pre-MW and 16 post-MW.ResultsAortic systolic BP during PEMI similarly increased in both groups. The increase in diastolic BP was lower in post-MW (post-MW Δ6 ± 2 vs pre-MW Δ11 ± 2 mm Hg, P < 0.05). Aortic PP (post-MW Δ8 ± 2 vs pre-MW Δ3 ± 2), Pf (post-MW Δ6 ± 1 vs pre-MW Δ0 ± 1), and Pb (post-MW Δ5 ± 1 vs pre-MW Δ2 ± 1) augmented during PEMI in post-MW (P < 0.05 for all), but not in pre-MW. Reflection magnitude increased during PEMI only in pre-MW (pre-MW Δ7 ± 2 vs post-MW Δ-1 ± 2, P < 0.05) due to concurrent increases in Pf and Pb in post-MW.ConclusionsEven in nonhypertensive postmenopausal women, increases in Pf and Pb and decrease in aortic DBP are important factors that contribute to the augmented aortic PP response to PEMI.

L-Citrulline supplementation attenuates aortic pressure and pressure waves during metaboreflex activation in postmenopausal women

“…The exaggerated BP response to PEMI is primarily regulated by sympathetic vasoconstriction since the increase in cardiac output is not greater in postmenopausal than young women (8,12) . We previously demonstrated an increased aortic PP response to PEMI was attributed to both augmented Pf and Pb in normotensive postmenopausal women (9) . Although IHG and PEMI did not increase Pf in young women and men (9,30) , Pf increased in postmenopausal women (9) .…”

“…During exercise, increases in stroke volume and sympathetic-mediated vasoconstriction contribute to augment SBP responses in young adults (8,29) . Evidence suggests that postmenopausal women have exaggerated sympathetic activation associated with increases in peripheral vasoconstriction during IHG (8,12) , which contributes to greater SBP responses compared with young women (9) . Exaggerated SBP and PP responses to maximal and IHG exercise are associated with increased left ventricular mass in middle-aged healthy women and individuals with hypertension (7,13) .…”

“…Elevated SBP during moderate- to high-intensity exercise is a predictor of cardiovascular mortality due to left ventricular remodeling in healthy middle-aged women (7) . Increased systolic and pulsatile load are also apparent during low-intensity exercise (8,9) , an exertion comparable to normal activities of daily living. Healthy postmenopausal women have exaggerated aortic SBP and Pf responses to low-intensity isometric handgrip exercise (IHG) compared with young counterparts (9) .…”

“…Increased systolic and pulsatile load are also apparent during low-intensity exercise (8,9) , an exertion comparable to normal activities of daily living. Healthy postmenopausal women have exaggerated aortic SBP and Pf responses to low-intensity isometric handgrip exercise (IHG) compared with young counterparts (9) . The blood pressure (BP) response to exercise is induced by an increase in sympathetic-mediated vasoconstriction via skeletal muscle mechano- and metaboreceptor activation.…”

“…Post-exercise muscle ischaemia (PEMI) following IHG is a manoeuver commonly used to isolate the metaboreflex by trapping muscle metabolites (10) and maintain sympathetic-mediated BP elevation (11) . Evidence suggests that metaboreflex overactivation in postmenopausal women (8,12) causes amplified aortic SBP, PP, Pf and Pb responses (9) , indicating greater left ventricular pulsatile load (1) . This pulsatile overload during exercise may cause ventricular hypertrophy and stiffness (7,13) , leading to heart failure in middle-aged women (7) .…”