title: Extending the time window for endovascular procedures according to collateral pial circulation.
abstract: OBJECTIVE
  Good collateral pial circulation (CPC) predicts a favorable outcome in patients undergoing intra-arterial procedures. We aimed to determine if CPC status may be used to decide about pursuing recanalization efforts.
  
  
  METHODS
  Pial collateral score (0-5) was determined on initial angiogram. We considered good CPC when pial collateral score<3, defined total time of ischemia (TTI) as onset-to-recanalization time, and clinical improvement>4-point decline in admission-discharge National Institutes of Health Stroke Scale.
  
  
  RESULTS
  We studied CPC in 61 patients (31 middle cerebral artery, 30 internal carotid artery). Good CPC patients (n=21 [34%]) had lower discharge National Institutes of Health Stroke Scale score (7 versus 21; P=0.02) and smaller infarcts (56 mL versus 238 mL; P<0.001). In poor CPC patients, a receiver operating characteristic curve defined a TTI cutoff point<300 minutes (sensitivity 67%, specificity 75%) that better predicted clinical improvement (TTI<300: 66.7% versus TTI>300: 25%; P=0.05). For good CPC patients, no temporal cutoff point could be defined. Although clinical improvement was similar for patients recanalizing within 300 minutes (poor CPC: 60% versus good CPC: 85.7%; P=0.35), the likelihood of clinical improvement was 3-fold higher after 300 minutes only in good CPC patients (23.1% versus 90.1%; P=0.01). Similarly, infarct volume was reduced 7-fold in good as compared with poor CPC patients only when TTI>300 minutes (TTI<300: poor CPC: 145 mL versus good CPC: 93 mL; P=0.56 and TTI>300: poor CPC: 217 mL versus good CPC: 33 mL; P<0.01). After adjusting for age and baseline National Institutes of Health Stroke Scale score, TTI<300 emerged as an independent predictor of clinical improvement in poor CPC patients (OR, 6.6; 95% CI, 1.01-44.3; P=0.05) but not in good CPC patients. In a logistic regression, good CPC independently predicted clinical improvement after adjusting for TTI, admission National Institutes of Health Stroke Scale score, and age (OR, 12.5; 95% CI, 1.6-74.8; P=0.016).
  
  
  CONCLUSIONS
  Good CPC predicts better clinical response to intra-arterial treatment beyond 5 hours from onset. In patients with stroke receiving endovascular treatment, identification of good CPC may help physicians when considering pursuing recanalization efforts in late time windows.
authors.affiliation: Unitat Neurovascular, Servei de Neurologia, Hospital Vall d'Hebron, Passeig Vall d'Hebron 119-129, Barcelona 08035, Spain. marcriboj@hotmail.com
authors.forename: Marc
authors.initials: M
authors.lastname: Ribo
authors.forename: Alan
authors.initials: A
authors.lastname: Flores
authors.forename: Marta
authors.initials: M
authors.lastname: Rubiera
authors.forename: Jorge
authors.initials: J
authors.lastname: Pagola
authors.forename: Joao
authors.initials: J
authors.lastname: Sargento-Freitas
authors.forename: David
authors.initials: D
authors.lastname: Rodriguez-Luna
authors.forename: Pilar
authors.initials: P
authors.lastname: Coscojuela
authors.forename: Olga
authors.initials: O
authors.lastname: Maisterra
authors.forename: Socorro
authors.initials: S
authors.lastname: Piñeiro
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Romero
authors.forename: Jose
authors.initials: J
authors.lastname: Alvarez-Sabin
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Molina
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000188:drug therapy / Q000503:physiopathology / Q000601:surgery*; D003097:Collateral Circulation; D057510:Endovascular Procedures / Q000379:methods*; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D020244:Infarction, Middle Cerebral Artery / Q000188:drug therapy / Q000503:physiopathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020768:Middle Cerebral Artery / Q000503:physiopathology / Q000601:surgery*; D020521:Stroke / Q000188:drug therapy / Q000503:physiopathology / Q000601:surgery*; D015912:Thrombolytic Therapy / Q000379:methods*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator