title: Recanalization and clinical outcome of occlusion sites at baseline CT angiography in the Interventional Management of Stroke III trial.
abstract: OBJECTIVE
  To use baseline computed tomographic (CT) angiography to analyze imaging and clinical end points in an Interventional Management of Stroke III cohort to identify patients who would benefit from endovascular stroke therapy.
  
  
  METHODS
  The primary clinical end point was 90-day dichotomized modified Rankin Scale (mRS) score. Secondary end points were 90-day mRS score distribution and 24-hour recanalization. Prespecified subgroup was baseline proximal occlusions (internal carotid, M1, or basilar arteries). Exploratory analyses were subsets with any occlusion and specific sites of occlusion (two-sided α = .01).
  
  
  RESULTS
  Of 656 subjects, 306 (47%) underwent baseline CT angiography or magnetic resonance angiography. Of 306, 282 (92%) had arterial occlusions. At baseline CT angiography, proximal occlusions (n = 220) demonstrated no difference in primary outcome (41.3% [62 of 150] endovascular vs 38% [27 of 70] intravenous [IV] tissue-plasminogen activator [tPA]; relative risk, 1.07 [99% confidence interval: 0.67, 1.70]; P = .70); however, 24-hour recanalization rate was higher for endovascular treatment (n = 167; 84.3% [97 of 115] endovascular vs 56% [29 of 52] IV tPA; P < .001). Exploratory subgroup analysis for any occlusion at baseline CT angiography did not demonstrate significant differences between endovascular and IV tPA arms for primary outcome (44.7% [85 of 190] vs 38% [35 of 92], P = .29), although ordinal shift analysis of full mRS distribution demonstrated a trend toward more favorable outcome (P = .011). Carotid T- or L-type occlusion (terminal internal carotid artery [ICA] with M1 middle cerebral artery and/or A1 anterior cerebral artery involvement) or tandem (extracranial or intracranial) ICA and M1 occlusion subgroup also showed a trend favoring endovascular treatment over IV tPA alone for primary outcome (26% [12 of 46] vs 4% [one of 23], P = .047).
  
  
  CONCLUSIONS
  Significant differences were identified between treatment arms for 24-hour recanalization in proximal occlusions; carotid T- or L-type and tandem ICA and M1 occlusions showed greater recanalization and a trend toward better outcome with endovascular treatment. Vascular imaging should be mandated in future endovascular trials to identify such occlusions. Online supplemental material is available for this article.
authors.affiliation: From the Calgary Stroke Program, Dept of Clinical Neurosciences and Radiology, Hotchkiss Brain Inst, Univ of Calgary, 1403 29 St NW, Room 112, Calgary, AB, Canada T2N 2T9 (A.M.D., M.G., E.Q., M.D.H.); Dept of Public Health Sciences, Medical Univ of South Carolina, Charleston, SC (S.D.Y., L.D.F., Y.Y.P.); Depts of Neurology and Rehabilitation Medicine and Radiology, Univ of Cincinnati Academic Health Ctr, Cincinnati, Ohio (J.C., P.K., T.A.T., J.P.B.); Stroke Inst, Univ of Pittsburgh Medical Ctr, Pittsburgh, Pa (T.G.J.); Neurovascular Unit, Dept of Neurology, Hosp Universitari Vall d'Hebron, Universitat Autonoma de Barcelona, Barcelona, Spain (M.R.); Melbourne Brain Ctr, The Royal Melbourne Hosp, Univ of Melbourne, Australia (B.Y.); Dept of Radiology, Medical College of Wisconsin, Milwaukee, Wis (O.O.Z.); Colorado Neurologic Inst, Denver, Colo (D.F.); Dept of Neuroradiology, Dresden Univ Stroke Ctr, Univ Hosp, Dresden, Germany (R.v.K.); Dept of Neurosurgery, Radiology and Public Health Sciences, Penn State M.S. Hershey Medical Ctr, Hershey, Pa (K.C.); and UCLA Stroke Ctr, Los Angeles, Calif (D.S.L.).
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
authors.forename: Mayank
authors.initials: M
authors.lastname: Goyal
authors.forename: Sharon D
authors.initials: SD
authors.lastname: Yeatts
authors.forename: Janice
authors.initials: J
authors.lastname: Carrozzella
authors.forename: Lydia D
authors.initials: LD
authors.lastname: Foster
authors.forename: Emmad
authors.initials: E
authors.lastname: Qazi
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hill
authors.forename: Tudor G
authors.initials: TG
authors.lastname: Jovin
authors.forename: Marc
authors.initials: M
authors.lastname: Ribo
authors.forename: Bernard
authors.initials: B
authors.lastname: Yan
authors.forename: Osama O
authors.initials: OO
authors.lastname: Zaidat
authors.forename: Donald
authors.initials: D
authors.lastname: Frei
authors.forename: Rüdiger
authors.initials: R
authors.lastname: von Kummer
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Cockroft
authors.forename: Pooja
authors.initials: P
authors.lastname: Khatri
authors.forename: David S
authors.initials: DS
authors.lastname: Liebeskind
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Tomsick
authors.forename: Yuko Y
authors.initials: YY
authors.lastname: Palesch
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Broderick
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D057510:Endovascular Procedures; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D020521:Stroke / Q000000981:diagnostic imaging* / Q000401:mortality / Q000628:therapy*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator