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Front Physiol. 2016 Jun 14;7:232. doi: 10.3389/fphys.2016.00232. eCollection 2016.

Slower Lower Limb Blood Pooling Increases Orthostatic Tolerance in Women with Vasovagal Syncope.

Frontiers in physiology

Johan Skoog, Helene Zachrisson, Toste Länne, Marcus Lindenberger

Affiliations

  1. Department of Medical and Health Sciences, Linköping University Linköping, Sweden.
  2. Department of Clinical Physiology and Department of Medical and Health Sciences, Linköping University Linköping, Sweden.
  3. Department of Cardiology and Department of Medical and Health Sciences, Linköping University Linköping, Sweden.

PMID: 27378941 PMCID: PMC4906053 DOI: 10.3389/fphys.2016.00232

Abstract

BACKGROUND AND AIM: Slower lower limb blood pooling and associated blunted sympathetic activation has been detected in healthy women prone to orthostatic syncope. Whether these findings are true also for patients with vasovagal syncope (VVS) is unknown. The aim was to investigate initial blood pooling time (poolingtime, time to 50% of total blood pooling) together with hemodynamic responses and orthostatic tolerance during lower body negative pressure (LBNP) in VVS and healthy controls.

METHODS AND RESULTS: Fourteen VVS women (25.7 ± 1.3 years) and 15 healthy women (22.8 ± 0.8 years) were subjected to single-step and graded LBNP to pre-syncope. Lower limb blood pooling (ml · 100 ml(-1)), poolingtime (s), hemodynamic responses and LBNP-tolerance were evaluated. LBNP induced comparable lower limb blood pooling in both groups (controls, 3.1 ± 0.3; VVS, 2.9 ± 0.3 ml · 100 ml(-1), P = 0.70). In controls, shorter poolingtime correlated to higher LBNP-tolerance (r = -0.550, P < 0.05) as well as better maintained stroke volume (r = -0.698, P < 0.01) and cardiac output (r = -0.563, P < 0.05). In contrast, shorter poolingtime correlated to lower LBNP-tolerance in VVS (r = 0.821, P < 0.001) and larger decline in stroke volume (r = 0.611, P < 0.05). Furthermore, in controls, shorter poolingtime correlated to baroreflex-mediated hemodynamic changes during LBNP, e.g., increased vasoconstriction (P < 0.001). In VVS, poolingtime was not correlated with LBNP-induced baroreceptor unloading, but rather highly correlated to resting calf blood flow (P < 0.001).

CONCLUSIONS: Shorter poolingtime seems to elicit greater sympathetic activation with a concomitant higher orthostatic tolerance in healthy women. The contrasting findings in VVS indicate a deteriorated vascular sympathetic control suggesting well-defined differences already in the initial responses during orthostatic stress.

Keywords: baroreceptors; blood pooling; hemodynamics; orthostatic intolerance; sympathetic nervous system; syncope; veins

References

  1. Clin Auton Res. 2004 Oct;14 Suppl 1:9-17 - PubMed
  2. Physiol Behav. 2013 Aug 15;120:34-9 - PubMed
  3. Acta Physiol Scand. 1989 Nov;137(3):325-34 - PubMed
  4. Europace. 2007 Feb;9(2):83-7 - PubMed
  5. Am J Physiol. 1998 Dec;275(6 Pt 2):R1909-20 - PubMed
  6. Acta Physiol Scand. 1992 Nov;146(3):299-306 - PubMed
  7. Hypertension. 1987 May;9(5):429-36 - PubMed
  8. Physiol Rep. 2015 Nov;3(11):null - PubMed
  9. Clin Sci (Lond). 2007 Feb;112(3):193-201 - PubMed
  10. Circulation. 2005 Jun 7;111(22):2997-3006 - PubMed
  11. Circulation. 2004 Oct 26;110(17):2575-81 - PubMed
  12. Am J Physiol Regul Integr Comp Physiol. 2016 Feb 1;310(3):R253-61 - PubMed
  13. Ann Neurol. 2002 Sep;52(3):342-5 - PubMed
  14. J Am Coll Cardiol. 1993 Apr;21(5):1193-8 - PubMed
  15. Am J Physiol Heart Circ Physiol. 2009 Jul;297(1):H53-8 - PubMed
  16. Exp Physiol. 2015 Jan;100(1):2-11 - PubMed
  17. Clin Sci (Lond). 2000 Jan;98(1):103-10 - PubMed
  18. Circulation. 2004 Nov 2;110(18):2931-7 - PubMed
  19. Am J Hypertens. 2012 Mar;25(3):319-24 - PubMed
  20. J Appl Physiol (1985). 1999 Oct;87(4):1555-63 - PubMed
  21. Am J Physiol Heart Circ Physiol. 2004 Jan;286(1):H449-57 - PubMed
  22. Hypertension. 2010 Dec;56(6):1118-23 - PubMed
  23. Am J Physiol Regul Integr Comp Physiol. 2011 Dec;301(6):R1831-7 - PubMed
  24. J Physiol. 2012 Apr 15;590(8):1839-48 - PubMed
  25. Basic Res Cardiol. 1978 Jan-Feb;73(1):77-84 - PubMed
  26. Circulation. 2003 Apr 1;107(12):1620-5 - PubMed
  27. Circulation. 2000 Feb 22;101(7):777-83 - PubMed
  28. Circulation. 1991 Sep;84(3):1016-23 - PubMed
  29. Am J Physiol Heart Circ Physiol. 2008 Aug;295(2):H867-73 - PubMed
  30. J Appl Physiol (1985). 2003 Jul;95(1):342-7 - PubMed
  31. Heart Rhythm. 2008 Dec;5(12):1695-701 - PubMed
  32. Cardiol Clin. 2013 Feb;31(1):75-87 - PubMed
  33. Prog Cardiovasc Dis. 2013 Jan-Feb;55(4):345-56 - PubMed
  34. Clin Sci (Lond). 2009 Sep 07;117(10):345-53 - PubMed
  35. Circulation. 2000 Dec 5;102(23):2898-906 - PubMed
  36. Am J Physiol Heart Circ Physiol. 2002 May;282(5):H1804-9 - PubMed
  37. Med Sci Sports Exerc. 1995 May;27(5):697-706 - PubMed
  38. Eur Heart J. 2009 Nov;30(21):2631-71 - PubMed
  39. Eur J Appl Physiol. 2015 Feb;115(2):245-56 - PubMed
  40. Am J Physiol Heart Circ Physiol. 2005 Jan;288(1):H103-10 - PubMed
  41. Am J Physiol Regul Integr Comp Physiol. 2007 Feb;292(2):R852-9 - PubMed
  42. J Clin Invest. 1997 Jun 1;99(11):2736-44 - PubMed
  43. Acta Physiol Scand. 1993 Feb;147(2):163-72 - PubMed
  44. Am J Physiol. 1985 Apr;248(4 Pt 2):H468-76 - PubMed
  45. Hypertension. 2007 Nov;50(5):899-903 - PubMed
  46. J Hypertens. 2004 Jul;22(7):1371-80 - PubMed
  47. J Physiol. 2009 Oct 15;587(Pt 20):4987-99 - PubMed

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