Relation between baroreflex sensitivity and carotid artery
elasticity in healthy humans.
Bonyhay, Istvan, Gabor Jokkel, and Mark Kollai.
Clinical Research Department and Second Institute of Physiology,
Semmelweis University of Medicine, Budapest, Hungary
APStracts 3:0130H, 1996.
We investigated whether physiological variability in arterial
baroreflex sensitivity (BRS) was related to differences in carotid
elastic behaviour among 19 young, healthy subjects (age 18-26). The
diameter of the carotid artery (D) and its change during the arterial
pulse (_D) was monitored by a phase-locked echo - tracking device (
UT-4 Hokanson) and pulse pressure (_P) was measured in the brachial
artery by sphygmomanometry. Distensibility coefficient (DC) for the
common carotid artery was calculated using the formula: DC = (2 x
_D/D) / _P. Dynamic elastic parameters such as the maximum and mean
rate of carotid artery expansion and the dominant harmonic frequency
(FFT) of the diameter curve were also determined. BRS was assessed by
regressing R-R intervals against systolic blood pressure, monitored
by FINAPRES, during an elevation of pressure, induced by i.v. bolus
injection of phenylephrine. By using correlation and stepwise
regression analysis we found that BRS was significantly related to
carotid artery distensibility (r = 0.778, P < 0.001), but was
not related to any of dynamic parameters of carotid pulsation.
Received 13 November 1995; accepted in final form 25 March 1996.
APS Manuscript Number H1063-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 1 April 96