Influence of vagal control on sex-related differences in left ventricular mechanics and hemodynamics
American Physiological Society
MetadataDangos cofnod eitem llawn
Left ventricular (LV) twist mechanics differ between men and women during acute physiological stress, which may be partly mediated by sex differences in autonomic control. While men appear to have greater adrenergic control of LV twist, the potential contribution of vagal modulation to sex differences in LV twist remains unknown. Therefore, the present study examined the role of vagal control on sex differences in LV twist during graded lower body negative pressure (LBNP) and supine cycling. On two separate visits, LV mechanics were assessed using two-dimensional speckle-tracking echocardiography in 18 men (22 ± 2 yr) and 17 women (21 ± 4 yr) during −40- and −60-mmHg LBNP and 25% and 50% of peak supine cycling workload with and without glycopyrrolate (vagal blockade). LV twist was not different at baseline but was greater in women during −60 mmHg in both control (women: 16.0 ± 3.4° and men: 12.9 ± 2.3°, P = 0.004) and glycopyrrolate trials (women: 17.7 ± 5.9° and men: 13.9 ± 3.3°, P < 0.001) due to greater apical rotation during control (women: 11.9 ± 3.6° and men: 7.8 ± 1.5°, P < 0.001) and glycopyrrolate (women: 11.6 ± 4.9° and men: 7.1 ± 3.6°, P = 0.009). These sex differences in LV twist consistently coincided with a greater LV sphericity index (i.e., ellipsoid geometry) in women compared with men. In contrast, LV twist did not differ between the sexes during exercise with or without glycopyrrolate. In conclusion, women have augmented LV twist compared with men during large reductions to preload, even during vagal blockade. As such, differences in vagal control do not appear to contribute to sex differences in the LV twist responses to physiological stress, but they may be related to differences in ventricular geometry.
American Journal of Physiology: Heart and Circulatory Physiology;
Williams, A.M., Shave, R.E., Coulson, J.M., White, H., Rosser-Stanford, B. and Eves, N.D. (2018) 'Influence of vagal control on sex-related differences in left ventricular mechanics and hemodynamics', American Journal of Physiology: Heart and Circulatory Physiology, 315(3), pp.H687-H698. DOI: 10.1152/ajpheart.00733.2017.
Dynodwr Gwrthrych Digidol (DOI)https://doi.org/10.1152/ajpheart.00733.2017
Article published in American Journal of Physiology: Heart and Circulatory Physiology on 31 August 2018, available at: https://doi.org/10.1152/ajpheart.00733.2017.
Cardiff Metropolitan University (Grant ID: Cardiff Metropolian (Internal))
- Sport Research Groups 
Yn dangos eitemau sy’n perthyn drwy deitl, awdur, pwnc a chrynodeb.
Williams, Alexandra; Shave, Rob; Cheyne, William; Eves, Neil (Wiley, 2017-02-11)Background. Sex differences in LV mechanics exist at rest and during acute physiological stress. Differences in cardiac autonomic and adrenergic control may contribute to sex differences in LV mechanics and LV hemodynamics. ...
Nio, Amanda; Stöhr, Eric J.; Shave, Rob (Taylor and Francis, 2017-08-08)Full Article Figures & data References Supplemental Citations Metrics Reprints & Permissions Get access Abstract Objectives: Cardiovascular function generally decreases with age, but whether this decrease ...
Effect of exercise training on left ventricular mechanics after acute myocardial infarction-an exploratory study McGregor, G.; Stöhr, Eric J.; Oxborough, D.; Kimani, P.; Shave, Rob (Elsevier, 2018-01-31)Background = Cardiac rehabilitation (CR) exercise training is beneficial after myocardial infarction (MI). Whilst the peripheral adaptations to training are well defined, little is known regarding the effect on left ...