Table 2

Summary of autonomic function tests in controls, hypertensive patients, and patients with unilateral or bilateral carotid artery stenosis

Controls
n=27
Hypertensive n=21Unilateral CAS n=23Bilateral CAS n=23
Orthostatic hypotension:
 On tilt or standing0 (0%)1 (5%)9 (39%)12 (52%)
Valsalva manoeuvre:
 Valsalva ratio (VR)1.62 (0.6)1.31 (0.05)1.14 (0.03)1.13 (0.03)
 Abnormal VR12 (57%)16 (69%)16 (69%)
Pressor responses:
 Isometric exercise
  Change in BP (mm Hg)17 (3)/11 (2)16 (3)/9 (2)16 (2)/13 (2)16 (4)/15 (4)
 Cold
  Change in BP (mm Hg)15 (2)/10 (2)13 (2)/12 (2)15 (2)/8 (2)11 (3)/6 (2)
 Diminished response0 (0%)0 (0%)1 (4%)
 Exaggerated response5 (24%)5 (22%)5 (22%)
Sinus arrhythmia:
 HR difference (beats/min)12 (1)10 (1)9 (1)6 (1)
  • VR=Valsalva ratio; BP=blood pressure; HR=heart rate.