title: Improved carotid hemodynamics with vertebral reconstruction.
abstract: This study tests the hypothesis that vertebral artery reconstruction improves carotid distribution hemodynamics during carotid occlusion. Twelve patients with vertebrobasilar symptoms underwent either direct (9) or indirect (3) vertebral reconstruction. There were six proximal vertebral to common carotid reimplantations, one proximal carotid-vertebral bypass and two distal carotid-vertebral bypasses, all with saphenous vein. Three patients with carotid-subclavian or axillo-axillary bypasses performed for symptomatic vertebral steal were studied at the time of carotid endarterectomy. During temporary ipsilateral carotid occlusion, vertebral reconstruction increased carotid back pressure from 39.3 +/- 10.2 mmHg to 46.8 +/- 9.5 mmHg (p less than 0.0001), increased cerebral perfusion pressure from 33.4 +/- 10.8 mmHg to 41.0 +/- 9.1 mmHg (p less than 0.0001), decreased the carotid collateral resistance to cerebral vascular resistance ratio from 1.68 +/- 0.90 to 1.24 +/- 0.64 (p less than 0.001), and increased the ratio of carotid back pressure to mean systemic arterial pressure from 0.452 +/- 0.122 to 0.515 +/- 0.118 (p = 0.0005). These results are presumed due to increased posterior-to-anterior blood flow in the posterior communicating arteries. Direct or indirect vertebral reconstruction may be a consideration in patients with cerebral ischemic symptomatic and nonreconstructible carotid occlusive disease.
authors.affiliation: Wake Medical Center, Raleigh, North Carolina.
authors.forename: J P
authors.initials: JP
authors.lastname: Archie
mesh_terms: D001794:Blood Pressure; D002339:Carotid Arteries / Q000503:physiopathology* / Q000601:surgery; D016893:Carotid Stenosis / Q000503:physiopathology* / Q000601:surgery; D002560:Cerebrovascular Circulation / Q000502:physiology*; D016894:Endarterectomy, Carotid; D006801:Humans; D007601:Jugular Veins / Q000502:physiology; D014655:Vascular Resistance; D014711:Vertebral Artery / Q000601:surgery*; D014715:Vertebrobasilar Insufficiency / Q000503:physiopathology / Q000601:surgery*