title: Intravenous tissue plasminogen activator and flow improvement in acute ischemic stroke patients with internal carotid artery occlusion.
abstract: OBJECTIVE
  It has been suggested that intravenous tissue plasminogen activator (TPA) would not lyse the large thrombus associated with internal carotid artery (ICA) occlusion and, therefore, would be ineffective in this setting. Vascular imaging, safety, and outcome of TPA therapy for ICA occlusion is not well described. Our goal was to determine the site of occlusion, early recanalization after TPA infusion, and its relationship to outcome.
  
  
  METHODS
  We reviewed our database of all stroke patients treated with i.v. TPA between July 1997 and July 1999. We identified all cases with carotid occlusion suggested by transcranial Doppler (TCD) and angiography. Occlusion and recanalization were assessed by site including proximal ICA (prICA), terminal ICA (tICA), and middle cerebral artery (MCA). Baseline National Institutes of Health Stroke Scale (NIHSS) scores and follow-up Rankin scores were obtained.
  
  
  RESULTS
  We treated 20 patients with carotid occlusion (age 63.9 +/- 10.8 years, 11 males, 9 females). Time to TPA infusion after stroke onset was 128 +/- 66 minutes. Baseline NIHSS scores were 16.4 +/- 5.4. Time to follow-up was 3.5 +/- 4.9 months (2 patients were lost to follow-up). Occlusion sites were prICA 40%, tICA 70%, and concurrent MCA 45%. Multiple sites were involved in 10/20 patients (50%). Among patients with pretreatment and posttreatment vascular imaging studies (n = 18), recanalization in the prICA and tICA was complete in 10%, partial in 16%, and none in 74%. MCA recanalization was complete in 35%, partial in 24%, and none in 41%. At follow-up, Rankin 0-1 was found in 8 patients (44%), Rankin 2-3 in 3 (17%), and Rankin 4-5 in 3 (17%). Mortality was 22% (n = 4) including 1 fatal intracerebral hemorrhage. Improvement was closely related to resumption of MCA flow (P < .01).
  
  
  CONCLUSIONS
  Most patients did not recanalize their ICA occlusion after intravenous TPA therapy. However, recanalization of associated proximal MCA clot, found in 45% of our patients, or improved MCA collateral flow was strongly associated with good outcome.
authors.affiliation: Department of Neurology, University of Texas-Houston Medical School, 6431 Fannin, MSB 7.044, Houston, TX 77030, USA.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Christou
authors.forename: Robert A
authors.initials: RA
authors.lastname: Felberg
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
authors.forename: W Scott
authors.initials: WS
authors.lastname: Burgin
authors.forename: Marc
authors.initials: M
authors.lastname: Malkoff
authors.forename: James C
authors.initials: JC
authors.lastname: Grotta
authors.forename: Andrei V
authors.initials: AV
authors.lastname: Alexandrov
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity; D002545:Brain Ischemia / Q000175:diagnosis* / Q000209:etiology*; D002343:Carotid Artery, Internal; D016893:Carotid Stenosis / Q000150:complications* / Q000188:drug therapy*; D002533:Cerebral Angiography; D002560:Cerebrovascular Circulation; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D010959:Tissue Plasminogen Activator