title: Wave-energy patterns in carotid, brachial, and radial arteries: a noninvasive approach using wave-intensity analysis.
abstract: The study of wave propagation at different points in the arterial circulation may provide useful information regarding ventriculoarterial interactions. We describe a number of hemodynamic parameters in the carotid, brachial, and radial arteries of normal subjects by using noninvasive techniques and wave-intensity analysis (WIA). Twenty-one normal adult subjects (14 men and 7 women, mean age 44 +/- 6 yr) underwent applanation tonometry and pulsed-wave Doppler studies of the right common carotid, brachial, and radial arteries. After ensemble averaging of the pressure and flow-velocity data, local hydraulic work was determined and a pressure-flow velocity loop was used to determine local wave speed. WIA was then applied to determine the magnitude, timings, and energies of individual waves. At all sites, forward-traveling (S) and backward-traveling (R) compression waves were observed in early systole. In mid- and late systole, forward-traveling expansion waves (X and D) were also seen. Wave speed was significantly higher in the brachial (6.97 +/- 0.58 m/s) and radial (6.78 +/- 0.62 m/s) arteries compared with the carotid artery (5.40 +/- 0.34 m/s; P < 0.05). S-wave energy was greatest in the brachial artery (993.5 +/- 87.8 mJ/m2), but R-wave energy was greatest in the radial artery (176.9 +/- 19.9 mJ/m2). X-wave energy was significantly higher in the brachial and radial arteries (176.4 +/- 32.7 and 163.2 +/- 30.5 mJ/m2, respectively) compared with the carotid artery (41.0 +/- 9.4 mJ/m2; P < 0.001). WIA illustrates important differences in wave patterns between peripheral arteries and may provide a method for understanding ventriculo-arterial interactions in the time domain.
authors.affiliation: Dept. of Clinical Pharmacology, 10th Floor QEQM, St. Mary's Hospital, London W2 1NY, UK.
authors.forename: A
authors.initials: A
authors.lastname: Zambanini
authors.forename: S L
authors.initials: SL
authors.lastname: Cunningham
authors.forename: K H
authors.initials: KH
authors.lastname: Parker
authors.forename: A W
authors.initials: AW
authors.lastname: Khir
authors.forename: S A
authors.initials: SA
authors.lastname: McG Thom
authors.forename: A D
authors.initials: AD
authors.lastname: Hughes
mesh_terms: D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000502:physiology*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D017534:Radial Artery / Q000000981:diagnostic imaging / Q000502:physiology*; D012039:Regional Blood Flow; D014463:Ultrasonography