Post-exercise effects on aortic wave reflection derived from wave separation analysis in young- to middle-aged pre-hypertensives and hypertensives

Eur J Appl Physiol. 2016 Jul;116(7):1321-9. doi: 10.1007/s00421-016-3391-1. Epub 2016 May 12.

Abstract

Purpose: Decreases in brachial blood pressure (BP) may occur for several hours following a bout of exercise. Although aortic backward waves predict cardiovascular damage independent of brachial BP, whether decreases in aortic backward waves also occur post-exercise in young-to-middle-aged hypertensives, the extent to which these changes exceed brachial BP changes, and the best method of identifying these changes is uncertain.

Methods: We examined aortic function at baseline and 15-min post-exercise in 20 pre-hypertensive or hypertensive men and women (age 45 ± 7 years). Central aortic pressure, forward (Pf) and backward (Pb) wave pressures, the reflection index (RI) and augmentation pressure (AP) and index (AIx) were determined using applanation tonometry, and SphygmoCor software.

Results: Decreases in central aortic (p < 0.001) but not brachial systolic BP and pulse pressure (PP) occurred post-exercise. In addition, decreases in post-exercise (baseline versus post-exercise) Pb (19 ± 4 vs 13 ± 3 mm Hg p < 0.0001), RI (72.9 ± 22.1 vs 47.6 ± 12.8 %, p < 0.0001), AIx (26.3 ± 10.8 vs 7.8 ± 11.6 %, p < 0.0001) and AP (9.9 ± 3.9 vs 2.8 ± 3.9 mm Hg, p < 0.0001), but not Pf, were noted. However, decreases in AIx were not correlated with decreases in Pb, and whilst decreases in aortic PP correlated with decreases in Pb (p < 0.0001), no correlations were noted with decreases in AP or AIx.

Conclusion: In young-to-middle-aged pre-hypertensive and hypertensive individuals, aortic backward waves decrease post-exercise; this change is not reflected in brachial BP measurements and is poorly indexed by measures of pressure augmentation.

Keywords: Aerobic exercise; Forward wave; Reflected wave.

MeSH terms

  • Adult
  • Aging
  • Aorta / physiopathology*
  • Blood Flow Velocity*
  • Blood Pressure*
  • Brachial Artery / physiopathology
  • Exercise*
  • Female
  • Humans
  • Hypertension / physiopathology*
  • Male
  • Middle Aged
  • Pulse Wave Analysis / methods*
  • Reproducibility of Results
  • Sensitivity and Specificity