Vol 21, No 4 (2017)
Original paper
Published online: 2017-08-11
Valsalva manoeuvre increases vagal baroreceptor unload reflex sensitivity in young healthy subjects
Arterial Hypertension 2017;21(4):167-170.
Abstract
Introduction. The objective was to verify the hypothesis that change in cardiovagal baroreceptor unload reflex sensitivity occurs between early phase 2 (VM2E) and phase 3 (VM3) of the Valsalva manoeuvre (VM). The study was performed on 29 volunteers between the ages of 25 and 40 (29.3 ± SE 4.0).
Material and methods. The experimental scheme was as follows: rest in sitting position, VM in sitting position maintaining an expiratory pressure of 20 mm Hg for 15 seconds, rest in sitting position. Changes in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured using Finapres.
Results. In VM2E and VM3, HR increased (+51.76 ± SE 4.06 beats/min., p < 0.001; +37.77 ± SE 8.65 beats/min., p < 0.0001, respectively) in response to a fall in SBP (–47.55 ± SE 3.95 mmHg, p < 0.001; –29.66 ± SE 2.80 mmHg, p < 0.0001; respectively). Both events of baroreceptor unload have been observed within the very similar range of SBP and HR.
Conclusion. The slope of regression relating change in heart rate (DHR) and systolic arterial pressure (DSBP) was significantly higher in VM3 (DHR2 = –1.063 × DSBP2 + 7.0986) than in VM2E (DHR1 = –0.4395 × DSBP2 + 30.862), suggesting the increased baroreceptors’ sensitivity toward SBP fall in VM3 compared to VM2E. VM increases vagal baroreceptor unloads reflex sensitivity.
Keywords: Valsalva manoeuvrebaroreceptor reflexvagal baroreflex sensitivityvagal baroreflex unload
References
- Frydrychowski AF, Wszedybyl-Winklewska M, Bandurski T, et al. Flow-induced changes in pial artery compliance registered with a non-invasive method in rabbits. Microvasc Res. 2011; 82(2): 156–162.
- Fu Qi, Okazaki K, Shibata S, et al. Menstrual cycle effects on sympathetic neural responses to upright tilt. J Physiol. 2009; 587(Pt 9): 2019–2031.
- Greenfield JC, Rembert JC, Tindall GT. Transient changes in cerebral vascular resistance during the Valsalva maneuver in man. Stroke. 1984; 15(1): 76–79.
- Hamilton WF, Woodbury RA, Harper HT. Physiological relationship between intrathoracic, intraspinal and arterial pressures. JAMA. 1944; 107: 853–856.
- Ogoh S, Tzeng YC, Lucas SJE, et al. Influence of baroreflex-mediated tachycardia on the regulation of dynamic cerebral perfusion during acute hypotension in humans. J Physiol. 2010; 588(Pt 2): 365–371.
- Smith ML, Beightol LA, Fritsch-Yelle JM, et al. Valsalva's maneuver revisited: a quantitative method yielding insights into human autonomic control. Am J Physiol. 1996; 271(3 Pt 2): H1240–H1249.
- Tiecks FP, Lam AM, Matta BF, et al. Effects of the valsalva maneuver on cerebral circulation in healthy adults. A transcranial Doppler Study. Stroke. 1995; 26(8): 1386–1392.
- Wszedybyl-Winklewska M, Frydrychowski AF, Michalska BM, et al. Effects of the Valsalva maneuver on pial artery pulsation and subarachnoid width in healthy adults. Microvasc Res. 2011; 82(3): 369–373.