title: Flow-mediated vasodilatation of carotid and brachial arteries in healthy subjects and in lacunar stroke patients.
abstract: The vasodilatory response of arteries can be measured by ultrasound, and it was previously shown that brachial artery (BA) vasodilatation can be tested by postischemic hyperemia. In the current study, the primary objective was to determine if hypercapnia can be used to assess common carotid artery (CCA) flow-mediated vasodilatation (FMVD) in healthy subjects. Secondary objectives were to investigate CCA-FMVD in lacunar patients and whether BA-FMVD parallels CCA-FMVD. We used ultrasound to measure flow-mediated and nitroglycerin (NTG)-mediated vasodilatation in the CCA and BA in 20 healthy subjects and in 17 lacunar patients. BA-FMVD was induced by a postischemic maneuver. For the CCA, FMVD was induced by hypercapnia from CO(2)-enriched inhalation. BA and CCA vasodilatation were measured after sublingual NTG administration. BA dilated significantly in healthy (6.7%) and stroke subjects (4.2%) under postischemic conditions. The CCA dilated significantly after CO(2) inhalation (11.4% in healthy subjects and 4% in lacunar patients) and NTG administration (18% in healthy subjects and 10.6% in lacunar patients). Surprisingly, there was a strong negative correlation between CCA- and BA-FMVD in healthy subjects. CCA vasodilatation induced by CO(2) inhalation and NTG administration can be measured. The strong negative correlation between CCA- and BA-FMVD suggests that there could be different mechanisms of vasodilatation.
authors.affiliation: Department of Neurology and Stroke Centre, Bichat University Hospital and Medical School, Paris, France. philippa.lavallee@bch.aphp.fr
authors.forename: Philippa C
authors.initials: PC
authors.lastname: Lavallée
authors.forename: Philippe
authors.initials: P
authors.lastname: Bonnin
authors.forename: Julien
authors.initials: J
authors.lastname: Labreuche
authors.forename: Pierre
authors.initials: P
authors.lastname: Amarenco
authors.forename: Bernard
authors.initials: B
authors.lastname: Lévy
mesh_terms: D001783:Blood Flow Velocity; D001916:Brachial Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging* / Q000503:physiopathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D005996:Nitroglycerin / Q000494:pharmacology; D012039:Regional Blood Flow; D020521:Stroke / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014463:Ultrasonography; D014655:Vascular Resistance; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D014665:Vasodilator Agents; D005996:Nitroglycerin