title: [Systematic review of complications for proper informed consent (9) periprocedural complications of carotid artery stenting: a review article].
abstract: BACKGROUND
  Carotid artery stenting(CAS)is a common procedure for the treatment of high surgical risk patients with carotid artery stenosis. Recent clinical study failed to show the non-inferiority of CAS to carotid endarterectomy(CEA)because of higher complication rates of CAS. However the result of a multicenter case study in Japan with tailored application of adequate devices including stents and protection devices revealed the safety of CAS in Japan. In this article the overall review in the previous reports of CAS are reviewed focusing on the complications and clinical outcome.
  
  
  METHODS
  Five randomized controlled trials concerning CAS versus CEA and 14 case series of CAS were reviewed, and the rates of periprocedural complications of CAS including death, stroke, myocardial infarction, hypotension and bradycardia, cranial nerve palsy, major vascular injury, cholesterol crystal embolization and hyperperfusion syndrome were summarized.
  
  
  RESULTS
  Mortality within 30 days of procedures was 0.9%. The rate of any stroke was 6.0% from the five RCT results, but a recent 14-case series reported any stroke rate at 3-4% and severe stroke rate at 1-2% respectively. The rates of acute myocardial infarction, hypotension, and bradycardia were 1%, 4%, and 4-12% respectively. The rate of bleeding complication of the access root was about 2% and non-bleeding was 1-2%. Cholesterol crystal embolization occurred in 0.2%. Incidence of hyperperfusion syndrome occurred in 1.5%, and intracranial hemorrhage in 0.8%.
  
  
  CONCLUSIONS
  Historically, the rapid improvement of devices and technical skills have contributed to the better clinical results. Also the lessons from complication cases have led to more appropriate indication and perfect protection to avoid adverse events. Therefore the rate of complication is always improving and those written in this article may not reflect the present real number. This article should be quoted with the previous reference as well as the newest data according to the operator's own experiences on taking informed consent.
authors.affiliation: Department of Neurosurgery, Nagoya University Graduate School of Medicine.
authors.forename: Takumi
authors.initials: T
authors.lastname: Asai
authors.forename: Shigeru
authors.initials: S
authors.lastname: Miyachi
authors.forename: Takashi
authors.initials: T
authors.lastname: Izumi
authors.forename: Noriaki
authors.initials: N
authors.lastname: Matsubara
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamanouchi
authors.forename: Keisuke
authors.initials: K
authors.lastname: Ota
authors.forename: Keiko
authors.initials: K
authors.lastname: Oda
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Wakabayashi
mesh_terms: D002339:Carotid Arteries / Q000601:surgery*; D016893:Carotid Stenosis / Q000150:complications / Q000601:surgery*; D002986:Clinical Trials as Topic; D016894:Endarterectomy, Carotid / Q000379:methods; D006801:Humans; D007258:Informed Consent; D011183:Postoperative Complications / Q000209:etiology* / Q000601:surgery; D015607:Stents