title: Tissue Window in Stroke Thrombolysis study (TWIST): a safety study.
abstract: BACKGROUND
  Stroke thrombolysis is limited by the "last-seen well" principle, which defines stroke onset time. A significant minority of stroke patients (~15%) awake with their symptoms and are by definition ineligible for thrombolysis because they were "last-seen well" at the time they went to bed implying an interval that is most often greater than three hours.
  
  
  METHODS
  A single-centre prospective, safety study was designed to thrombolyse 20 subjects with stroke-on-awakening. Patients were eligible for inclusion if they were last seen well less than 12 hours previously, specifically including those who awoke from sleep with their stroke deficits. They had a baseline computed tomogram (CT) scan with an ASPECTS score greater than 5, no evidence of well-evolved infarction and a CT angiogram / Trans-cranial Doppler ultrasound study demonstrating an intracranial arterial occlusion. Patients fulfilled all other standard criteria for stroke thrombolysis. The primary outcome was safety defined by symptomatic ICH or death.
  
  
  RESULTS
  Among 89 screened patients, 20 were treated with thrombolysis. Two patients (10%) died due to massive carotid territory stroke and two patients (10%) died of stroke complications. Two patients (10%) showed asymptomatic intracerebral hemorrhage (ICH) (petechial hemorrhage) and none symptomatic ICH. Reasons for exclusion were: (a) ASPECTS ≤ 5 (29); (b) well-evolved infarcts on CT (19); (c) historical mRS > 2 (17); (d) no demonstrable arterial occlusion or were too mild to warrant treatment (10).
  
  
  CONCLUSIONS
  Patients who awake with their deficits can be safely treated with thrombolysis based upon a tissue window defined by NCCT and CTA/TCD.
authors.affiliation: Calgary Stroke Program, Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada. michael.hill@ucalgary.ca
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hill
authors.forename: Carol
authors.initials: C
authors.lastname: Kenney
authors.forename: Imanuel
authors.initials: I
authors.lastname: Dzialowski
authors.forename: Jean-Martin
authors.initials: JM
authors.lastname: Boulanger
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Demchuk
authors.forename: Philip A
authors.initials: PA
authors.lastname: Barber
authors.forename: Timothy W J
authors.initials: TW
authors.lastname: Watson
authors.forename: Nicolas U
authors.initials: NU
authors.lastname: Weir
authors.forename: Alastair M
authors.initials: AM
authors.lastname: Buchan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020521:Stroke / Q000000981:diagnostic imaging / Q000628:therapy*; D015912:Thrombolytic Therapy / Q000379:methods*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018616:Ultrasonography, Doppler, Duplex; D014851:Wakefulness
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator