title: Restenosis after carotid artery stenting using a specific designed ultrasonographic protocol.
abstract: BACKGROUND
  Nowadays, the number of patients undergoing carotid artery stenting (CAS) is increasing rapidly, and these patients require follow-up to monitor the patency of the device and the potential development of an in-stent restenosis (ISR).
  
  
  METHODS
  Patients undergoing CAS at our institution underwent duplex ultrasound (DUS) at 6 months, 12 months, and yearly thereafter, using a prespecified protocol. Restenosis was defined as a more than 50% diameter-reducing stenosis. Patients with DUS-diagnosed restenosis underwent carotid computerized tomography angiography (CTA) to confirm the presence of ISR. The frequency of restenosis was calculated by Kaplan-Meier survival estimates and was compared during a 2-year follow-up period. Interactions between restenosis and baseline variables were assessed using odds ratio.
  
  
  RESULTS
  Between August 2007 and March 2012 were performed 100 procedures in 96 patients, with a median age of 72.9 years. The mean duration of follow-up was 29.2 months (±8.4). Restenosis occurred in 6 carotid arteries. The Kaplan-Meier estimate for the frequency of restenosis in 2 years was 6.0% and for severe restenosis was 3.0%. There were no occlusions. Diabetic patients seem to have a higher risk of ISR (OR=3.23, 95% CI .55-18.9). Carotid CTA was in agreement with the degree of stenosis estimated by DUS in all cases.
  
  
  CONCLUSIONS
  Our results, using a DUS protocol and a specific peak systolic velocity threshold, showed that the frequency of restenosis at 2 years after CAS is 6.0% and so that CAS is probably a durable revascularization procedure. We emphasize the diagnostic agreement achieved between DUS and carotid CTA.
authors.affiliation: Neurology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho. Electronic address: pedrojgbarros@gmail.com.
authors.forename: Pedro
authors.initials: P
authors.lastname: Barros
authors.affiliation: Neurology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho.
authors.forename: Helena
authors.initials: H
authors.lastname: Felgueiras
authors.affiliation: Stroke Unit, Centro Hospitalar de Vila Nova de Gaia/Espinho.
authors.forename: Dulce
authors.initials: D
authors.lastname: Pinheiro
authors.affiliation: Cardiothoracic Surgery Department, Centro Hospitalar de Vila Nova de Gaia/Espinho.
authors.forename: Miguel
authors.initials: M
authors.lastname: Guerra
authors.affiliation: Cardiology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal.
authors.forename: Vasco
authors.initials: V
authors.lastname: Gama
authors.affiliation: Neurology Department, Centro Hospitalar de Vila Nova de Gaia/Espinho; Stroke Unit, Centro Hospitalar de Vila Nova de Gaia/Espinho.
authors.forename: Miguel
authors.initials: M
authors.lastname: Veloso
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000601:surgery*; D016893:Carotid Stenosis / Q000000981:diagnostic imaging / Q000601:surgery*; D016894:Endarterectomy, Carotid / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015607:Stents; D016896:Treatment Outcome; D014463:Ultrasonography
keywords: Carotid; Doppler; restenosis; stenting; ultrasonography