title: Intracranial hemorrhage and hyperperfusion syndrome following carotid artery stenting: risk factors, prevention, and treatment.
abstract: OBJECTIVE
  The study defined the incidence of cerebral hyperperfusion syndrome and intracranial hemorrhage (ICH) and the risk factors for their development following carotid artery stenting (CAS).
  
  
  BACKGROUND
  Hyperperfusion syndrome and ICH can complicate carotid revascularization, be it endarterectomy or CAS. Although extensive effort has been devoted to reducing the incidence of ischemic stroke complicating CAS, little is known about the incidence, etiology, and prevention strategies for hyperperfusion and ICH following CAS.
  
  
  METHODS
  We retrospectively reviewed the prospective database of 450 consecutive patients who were treated with CAS in our department to identify patients who developed hyperperfusion syndrome and/or ICH.
  
  
  RESULTS
  The mean age of the patients was 72.7 +/- 10.9 years, and the mean diameter narrowing was 84 +/- 12.8%. Five (1.1% [95% confidence interval 0.4% to 2.6%]) patients developed hyperperfusion. Three (0.67%) of the five developed ICH. Two of these patients died (0.44%). Symptoms developed within a median of 10 h (range, 6 h to 4 days) following stenting. All five patients had correction of a severe internal carotid stenosis (mean 95.6 +/- 3.7%) with a concurrent contralateral stenosis >80% or contralateral occlusion and peri-procedural hypertension. These same risk factors are involved in cerebral hyperperfusion following carotid endarterectomy. The use of platelet glycoprotein IIb/IIIa receptor blockers did not appear to increase the risk ICH.
  
  
  CONCLUSIONS
  The hyperperfusion syndrome occurs infrequently following CAS, and ICH occurs in 0.67% of patients. Patients with severe bilateral carotid stenoses may be predisposed to ICH, particularly if there is concurrent arterial hypertension. Patients with these factors may require more intensive hemodynamic monitoring after CAS, including prolongation of hospitalization in some cases.
authors.affiliation: Department of Neurology, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Abou-Chebl
authors.forename: Jay S
authors.initials: JS
authors.lastname: Yadav
authors.forename: Joel P
authors.initials: JP
authors.lastname: Reginelli
authors.forename: Christopher
authors.initials: C
authors.lastname: Bajzer
authors.forename: Deepak
authors.initials: D
authors.lastname: Bhatt
authors.forename: Derk W
authors.initials: DW
authors.lastname: Krieger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019917:Blood Vessel Prosthesis Implantation; D002343:Carotid Artery, Internal / Q000601:surgery*; D016893:Carotid Stenosis / Q000601:surgery*; D003324:Coronary Artery Disease / Q000601:surgery; D004621:Embolization, Therapeutic; D016894:Endarterectomy, Carotid; D006261:Headache / Q000453:epidemiology / Q000209:etiology / Q000628:therapy; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology / Q000628:therapy; D015994:Incidence; D020300:Intracranial Hemorrhages / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D008875:Middle Aged; D009820:Ohio; D010477:Perfusion / Q000009:adverse effects*; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000627:therapeutic use; D011183:Postoperative Complications / Q000453:epidemiology / Q000209:etiology* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D015607:Stents; D013577:Syndrome; D016896:Treatment Outcome
chemical_list: D019039:Platelet Glycoprotein GPIIb-IIIa Complex