RT Journal Article
SR Electronic
T1 Cardiovascular, autonomic, and plasma catecholamine responses in unilateral and bilateral carotid artery stenosis
JF Journal of Neurology, Neurosurgery & Psychiatry
JO J Neurol Neurosurg Psychiatry
FD BMJ Publishing Group Ltd
SP 428
OP 432
DO 10.1136/jnnp.67.4.428
VO 67
IS 4
A1 Adeola Akinola
A1 Christopher J Mathias
A1 Averil Mansfield
A1 David Thomas
A1 John Wolfe
A1 A N Nicolaides
A1 Thomas Tegos
YR 1999
UL http://jnnp.bmj.com/content/67/4/428.abstract
AB OBJECTIVE To determine impairment of baroreceptor afferent activity, which may affect cardiovascular autonomic function in patients with unilateral and bilateral carotid artery stenosis. Comparison was made with normal subjects and hypertensive patients. METHODS A series of cardiovascular autonomic function tests along with plasma noradrenaline (norepinephrine) measurements were performed in 46 patients with carotid artery stenosis (CAS); 23 had unilateral and 23 had bilateral stenosis. Comparison was made with 21 hypertensive patients (with a similar degree of raised blood pressure), and 27 normal subjects. RESULTS Over a third of patients with unilateral and bilateral CAS had postural hypotension. Heart rate did not rise appropriately in CAS despite the postural fall in blood pressure. Pressor responses in CAS were preserved. Heart rate responses to respiratory stimuli were attenuated. Plasma noradrenaline concentrations rose normally during head up tilt. CONCLUSION A substantial proportion with CAS had postural hypotension and attenuated heart rate responses. This was not due to sympathetic vasoconstrictor or cardiac parasympathetic failure, thus suggesting impaired afferent baroreceptor activity, probably secondary to involvement of the carotid sinus. Cardiovascular autonomic testing and assessment of postural hypotension and factors enhancing it may be of clinical relevance in such patients, especially as the symptoms of postural hypotension overlap with those due to thromboembolism.