Gabriel H Zieff1, Kevin Heffernan2, Keeron Stone3, Simon Fryer3, Daniel Credeur4, Erik D Hanson1, James Faulkner5, Lee Stoner1. 1. Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. 2. Department of Exercise Science, Syracuse University, Syracuse, New York, USA. 3. Department of Sport, Exercise, Health and Wellbeing, University of Gloucestershire, Gloucester, UK. 4. School of Human Performance & Recreation, University of Southern Mississippi, Hattiesburg, Mississippi, USA. 5. Department of Sport & Exercise, University of Winchester, Winchester, UK.
Abstract
OBJECTIVE: To determine which ultrasound-based, single-point arterial stiffness estimate is least dependent on blood pressure (BP) to improve assessment of local vascular function. METHODS: Ultrasound was used to assess blood flow and diameters at the left brachial artery of 20 healthy adults [55% female, 27.9 years (5.2), 24.2 (2.8) kg/m]. BP of both arms was measured simultaneously. Experimental (left) arm BP was then systematically manipulated by adjusting its position ABOVE (+30°) and BELOW (-30°) heart level in a randomized order following measurement at heart level (0°). The control (right) arm remained at heart level. Six stiffness measurements were calculated: compliance, distensibility, beta-stiffness, and three estimates of pulse wave velocity (PWV) (Bramwell Hill, blood flow, and beta-stiffness). We considered the measurement technique with the least significant change across positions to be the least pressure-dependent. RESULTS: There was a large effect change in mean arterial pressure (np = 0.75, P < 0.001) in the experimental arm when it was ABOVE (Δ-4.4 mmHg) and BELOW (Δ10.4 mmHg) heart level. There was a main effect (P < 0.05) of arm position on all arterial stiffness measures. From least to most pressure-dependent, the arterial stiffness measurements were: PWV (blood flow method), compliance coefficient, beta-stiffness, distensibility coefficient, PWV (Bramwell-Hill method), and PWV (beta-stiffness index method). CONCLUSION: All single-point measures assessed are pressure-dependent. The PWV (blood flow method) may be the least pressure-dependent single-point measure, and may be the most suitable single-point measure to assess local vascular function.
RCT Entities:
OBJECTIVE: To determine which ultrasound-based, single-point arterial stiffness estimate is least dependent on blood pressure (BP) to improve assessment of local vascular function. METHODS: Ultrasound was used to assess blood flow and diameters at the left brachial artery of 20 healthy adults [55% female, 27.9 years (5.2), 24.2 (2.8) kg/m]. BP of both arms was measured simultaneously. Experimental (left) arm BP was then systematically manipulated by adjusting its position ABOVE (+30°) and BELOW (-30°) heart level in a randomized order following measurement at heart level (0°). The control (right) arm remained at heart level. Six stiffness measurements were calculated: compliance, distensibility, beta-stiffness, and three estimates of pulse wave velocity (PWV) (Bramwell Hill, blood flow, and beta-stiffness). We considered the measurement technique with the least significant change across positions to be the least pressure-dependent. RESULTS: There was a large effect change in mean arterial pressure (np = 0.75, P < 0.001) in the experimental arm when it was ABOVE (Δ-4.4 mmHg) and BELOW (Δ10.4 mmHg) heart level. There was a main effect (P < 0.05) of arm position on all arterial stiffness measures. From least to most pressure-dependent, the arterial stiffness measurements were: PWV (blood flow method), compliance coefficient, beta-stiffness, distensibility coefficient, PWV (Bramwell-Hill method), and PWV (beta-stiffness index method). CONCLUSION: All single-point measures assessed are pressure-dependent. The PWV (blood flow method) may be the least pressure-dependent single-point measure, and may be the most suitable single-point measure to assess local vascular function.
Authors: Avinash Chandran; Derek W Brown; Gabriel H Zieff; Zachary Y Kerr; Daniel Credeur; Lee Stoner Journal: Hypertens Res Date: 2021-01-28 Impact factor: 3.872