title: MRI-based intravenous thrombolysis in stroke patients with unknown time of symptom onset.
abstract: BACKGROUND
  Currently, stroke patients with unknown time of symptom onset (UTOS) are excluded from therapy with intravenous tissue Plasminogen Activator. We hypothesized that MRI-based intravenous thrombolysis is safe in UTOS.
  
  
  METHODS
  We analyzed radiological and clinical data as well as outcomes of stroke patients (including UTOS) who received intravenous thrombolytic therapy after MRI.
  
  
  RESULTS
  Compared to patients with known time of symptom onset (n=131), UTOS (n=17) were older (81, 71-88 vs. 75 years, 66-82, P=0.03), had a longer median time between last-seen-well and thrombolysis (12.3 h, IQR 11.5-15.2 h vs. 2.1 h, 1.8-2.8 h, P<0.01), had a longer median door-to-needle time (86 min, 49-112 vs. 60 min, 49-76, P=0.02), and a higher rate of arterial obstruction on MR-angiography (82.4% vs. 56.5%, P=0.04). No symptomatic intracerebral hemorrhage occurred in UTOS. After 3 months, there was no significant difference between groups concerning good functional outcome (modified Rankin Scale 0-2; 35.3% vs. 49.6%, P=0.26) or mortality (0% vs. 15.3%, P=0.08). In multivariate analyses including age, gender, baseline NIHSS, and atrial fibrillation UTOS did not have an independent effect on good functional outcome after 3 months (OR 1.16; 0.32-4.12, P=0.81).
  
  
  CONCLUSIONS
  Thrombolysis after MRI seems safe and effective in UTOS. This observation may encourage those who plan prospective placebo-controlled trials of thrombolytics in this subgroup of stroke patients.
authors: Center for Stroke Research Berlin (CSB), Charitéplatz, Berlin, Germany. martin.ebinger@charite.de
authors: M
authors: M
authors: Ebinger
authors: J F
authors: JF
authors: Scheitz
authors: A
authors: A
authors: Kufner
authors: M
authors: M
authors: Endres
authors: J B
authors: JB
authors: Fiebach
authors: C H
authors: CH
authors: Nolte
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002545:Brain Ischemia / Q000188:drug therapy*; D005260:Female; D005343:Fibrinolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D056687:Off-Label Use; D020521:Stroke / Q000188:drug therapy*; D015912:Thrombolytic Therapy / Q000009:adverse effects* / Q000379:methods; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator