title: MRI-based and CT-based thrombolytic therapy in acute stroke within and beyond established time windows: an analysis of 1210 patients.
abstract: OBJECTIVE
  The use of intravenous thrombolysis is restricted to a minority of patients by the rigid 3-hour time window. This window may be extended by using modern imaging-based selection algorithms. We assessed safety and efficacy of MRI-based thrombolysis within and beyond 3 hours compared with standard CT-based thrombolysis.
  
  
  METHODS
  Five European stroke centers pooled the core data of their CT- and MRI-based prospective thrombolysis databases. Safety outcomes were predefined as symptomatic intracranial hemorrhage and mortality. Primary efficacy outcome was a favorable outcome (modified Rankin Scale 0 to 1). We performed univariate and multivariate analyses for all end points, including age, National Institutes of Health Stroke Scale, treatment group (CT <3 hours, MRI <3 hours and >3 hours), and onset to treatment time as variables.
  
  
  RESULTS
  A total of 1210 patients were included (CT <3 hours: N=714; MRI <3 hours: N=316; MRI >3 hours: N=180). Median age, National Institutes of Health Stroke Scale, and onset to treatment time were 69, 67, and 68.5 years (P=0.66); 12, 13, and 14 points (P=0.019); and 130, 135, and 240 minutes (P<0.001). Symptomatic intracranial hemorrhage rates were 5.3%, 2.8%, and 4.4% (P=0.213); mortality was 13.7%, 11.7%, and 13.3% (P=0.68). Favorable outcome occurred in 35.4%, 37.0%, and 40% (P=0.51). Age and National Institutes of Health Stroke Scale were independent predictors for all safety and efficacy outcomes. The overall use of MRI significantly reduced symptomatic intracranial hemorrhage (OR: 0.520, 95% CI: 0.270 to 0.999, P=0.05). Beyond 3 hours, the use of MRI significantly predicted a favorable outcome (OR: 1.467; 95% CI: 1.017 to 2.117, P=0.040). Within 3 hours and for all secondary end points, there was a trend in favor of MRI-based selection over standard <3-hour CT-based treatment.
  
  
  CONCLUSIONS
  Despite significantly longer time windows and significantly higher baseline National Institutes of Health Stroke Scale scores, MRI-based thrombolysis is safer and potentially more efficacious than standard CT-based thrombolysis.
authors: Department of Neurology, University of Erlangen, Schwabachanlage 6, D-91054 Erlangen, Germany. Peter.Schellinger@uk-erlangen.de
authors: Peter D
authors: PD
authors: Schellinger
authors: Götz
authors: G
authors: Thomalla
authors: Jens
authors: J
authors: Fiehler
authors: Martin
authors: M
authors: Köhrmann
authors: Carlos A
authors: CA
authors: Molina
authors: Tobias
authors: T
authors: Neumann-Haefelin
authors: Marc
authors: M
authors: Ribo
authors: Oliver C
authors: OC
authors: Singer
authors: Olivier
authors: O
authors: Zaro-Weber
authors: Jan
authors: J
authors: Sobesky
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016208:Databases, Factual; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007262:Infusions, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D020521:Stroke / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D015912:Thrombolytic Therapy / Q000379:methods*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage*; D014057:Tomography, X-Ray Computed
chemical_list: D005343:Fibrinolytic Agents; D010959:Tissue Plasminogen Activator