title: One patent intracranial collateral predicts tolerance of flow reversal during carotid angioplasty and stenting.
abstract: Internal carotid artery (ICA) flow reversal is an effective means of cerebral protection during carotid stenting. Its main limitation is that in the absence of adequate collateral flow it may not be tolerated by the patient. The purpose of this study was to determine if preoperative identification of intracranial collaterals with computerized tomographic (CTA) or magnetic resonance (MRA) angiography can predict adequate collateral flow and neurological tolerance of ICA flow reversal for embolic protection. This was a study of patients undergoing transcervical carotid angioplasty and stenting. Neuroprotection was established by ICA flow reversal. All patients underwent preoperative cervical and cerebral noninvasive angiography with CTA or MRA and had at least one patent intracranial collateral. Mean carotid artery back pressure was measured. Neurological changes during carotid clamping and flow reversal were continuously monitored with electroencephalography (EEG). Thirty-seven patients with at least one patent intracranial collateral on brain imaging with CTA or MRA were included. Mean carotid artery back pressure was 58 mm Hg. All procedures were technically successful. No EEG changes were present with common carotid artery occlusion and ICA flow reversal. One patent intracranial collateral provides sufficient cerebral perfusion to perform carotid occlusion and flow reversal with absence of EEG changes. Continued progress in noninvasive imaging modalities is becoming increasingly helpful in our understanding of cerebral physiology and selection of patients for invasive carotid procedures.
authors.affiliation: Department of Surgery, University of Nebraska Medical Center, Omaha, NE 68198-3280, USA. ipipinos@unmc.edu
authors.forename: Iraklis I
authors.initials: II
authors.lastname: Pipinos
authors.forename: George T
authors.initials: GT
authors.lastname: Pisimisis
authors.forename: Sathyaprasad C
authors.initials: SC
authors.lastname: Burjonrappa
authors.forename: Jason M
authors.initials: JM
authors.lastname: Johanning
authors.forename: G Matthew
authors.initials: GM
authors.lastname: Longo
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Lynch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017130:Angioplasty / Q000009:adverse effects / Q000295:instrumentation; D001794:Blood Pressure; D002343:Carotid Artery, Internal / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D016893:Carotid Stenosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D002533:Cerebral Angiography / Q000379:methods; D002560:Cerebrovascular Circulation; D002561:Cerebrovascular Disorders / Q000209:etiology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D002941:Circle of Willis / Q000473:pathology / Q000503:physiopathology*; D003097:Collateral Circulation; D004569:Electroencephalography; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D010477:Perfusion; D011237:Predictive Value of Tests; D012039:Regional Blood Flow; D012189:Retrospective Studies; D012720:Severity of Illness Index; D015607:Stents; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014654:Vascular Patency