Related Experiment Video

Updated: May 30, 2026

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research
08:42

Ultrasound Assessment of Endothelial-Dependent Flow-Mediated Vasodilation of the Brachial Artery in Clinical Research

Published on: October 22, 2014

Low flow-mediated constriction: prevalence, impact and physiological determinant

Michelle Harrison1, Kristin Parkhurst, Takashi Tarumi

  • 1Cardiovascular Aging Research Laboratory, Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX, USA.

Clinical Physiology and Functional Imaging
|July 21, 2011
PubMed

Insights

Brachial artery responses during cuff inflation vary significantly. Accounting for low flow-mediated constriction (L-FMC) offers a more complete endothelial function assessment, especially in individuals with coronary artery disease risk factors.

Area of Science:

  • Cardiovascular physiology
  • Endothelial function assessment
  • Vascular reactivity studies

Background:

  • Flow-mediated dilation (FMD) is a key indicator of endothelial function.
  • The brachial artery's response during cuff inflation (low flow-mediated constriction, L-FMC) is often overlooked.
  • L-FMC variability may influence FMD measurements and reflect underlying vascular health.

Purpose of the Study:

  • To investigate brachial artery response variability during cuff inflation across diverse coronary artery disease (CAD) risk profiles.
  • To determine the impact of L-FMC on standard FMD calculations.
  • To explore the relationship between L-FMC, FMD, and arterial stiffness.

Main Methods:

  • Assessed L-FMC, traditional FMD, and modified FMD in 46 subjects with varied CAD risk factors.
  • Measured brachial artery diameter changes during cuff inflation.
  • Correlated L-FMC with FMD and arterial stiffness parameters (pulse wave velocity).

Main Results:

  • Brachial artery responses during inflation ranged from vasoconstriction (-5.6%) to vasodilation (5.0%).
  • Modified FMD differed significantly between healthy and high-risk groups (P=0.02), unlike traditional FMD.
  • L-FMC correlated with FMD (r=0.41) and arterial stiffness (r=0.30).

Conclusions:

  • Brachial artery responses to cuff inflation are highly variable.
  • Incorporating L-FMC into FMD analysis provides a more nuanced assessment of endothelial function.
  • Arterial stiffness is associated with L-FMC, highlighting its clinical relevance in cardiovascular risk evaluation.

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