Effects of transient change in carotid arterial stiffness on arterial baroreflex during mild orthostatic stimulation
Year: 2012
Type: article
Abstract: Stiffening of central conduit arteries eareas where the mechanoreceptors are embedded (e.g., ascending aorta and carotid artery) e is considered to be associated with the impaired baroreflex control in response to hypotensive stress.Arterial stiffness is modulated by vascular tone transiently and dynamically, however, it is unknown whether a transient change in the carotid artery stiffness influences the cardiac baroreflex response to a rapid hypotension.We measured (n Z 11) carotid arterial stiffness (via concurrent applanation tonometory and ultrasound imaging) at supine rest and during 20-degree head-up tilt (HUT).To evaluate the cardiac baroreflex response, acute hypotension was evoked by releasing bilateral thigh cuffs after 3 min of suprasystolic resting ischemia at each posture; cardiac baroreflex sensitivity (e.g., change in heart rate for a given change in mean arterial pressure, DHR/DMAP) and latency (e.g., the time to peak HR response) was estimated.Carotid b-stiffness index, a measure of arterial stiffness, was reduced by 14% during HUT (P < 0.05 vs. supine position).Although cardiac baroreflex responses were unaltered, the within-group biological variability in the cardiac baroreflex sensitivity and latency from the supine to HUT was correlated with the corresponding changes in carotid arterial stiffness (r Z 0.66 and r Z 0.64, respectively, both P < 0.05).These findings suggest that a transient change in carotid arterial stiffness, at least in part, influences changes in the cardiac baroreflex response to a rapid hypotension.
Source: Artery Research
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $1,790
OpenAlex ID: W2093379730