title: MRI versus CT-based thrombolysis treatment within and beyond the 3 h time window after stroke onset: a cohort study.
abstract: BACKGROUND
  Thrombolytic treatment with recombinant tissue plasminogen activator (rtPA) is approved for use within 3 h after stroke onset. Thus only a small percentage of patients can benefit. Meta-analyses and more recent studies suggest a benefit for a subset of patients beyond 3 h. We assessed the safety and efficacy of an MRI-based selection protocol for stroke treatment within and beyond 3 h compared with standard CT-based treatment.
  
  
  METHODS
  We assessed clinical outcome and incidence of symptomatic intracerebral haemorrhage (ICH) in 400 consecutive patients treated with intravenous rtPA. Patients eligible for thrombolysis within 3 h were selected by CT or MRI and beyond 3 h only by MRI. 18 patients were excluded from analysis because of violation of that algorithm. The remaining 382 patients were divided into three groups: CT-based treatment within 3 h (n=209); MRI-based treatment within 3 h (n=103); and MRI-based treatment beyond 3 h (n=70).
  
  
  RESULTS
  Patients in group 3 (MRI > 3 h) had a similar 90 day outcome to those in the other two groups (48% were independent in the CT < or = 3 h group, 51% in the MRI < or = 3 h group, and 56% in group 3), but without an increased risk for symptomatic ICH (9%, 1%, 6%) or mortality (21%, 13%, 11%). MRI-selected patients overall had a significantly lower risk than CT-selected patients for symptomatic ICH (3% vs 9%; p=0.013) and mortality (12% vs 21%; p=0.021). Time to treatment did not affect outcomes in univariate and multivariate analyses.
  
  
  CONCLUSIONS
  Our data suggest that beyond 3 h and maybe even within 3 h, patient selection is more important than time to treatment for a good outcome. Furthermore, MRI-based thrombolysis, irrespective of the time window, shows an improved safety profile while being at least as effective as standard CT-based treatment within 3 h.
authors.affiliation: Department of Neurology, University of Heidelberg, Heidelberg, Germany. martin.koehrmann@neuro.imed.uni-erlangen.de
authors.forename: Martin
authors.initials: M
authors.lastname: Köhrmann
authors.forename: Eric
authors.initials: E
authors.lastname: Jüttler
authors.forename: Jochen B
authors.initials: JB
authors.lastname: Fiebach
authors.forename: Hagen B
authors.initials: HB
authors.lastname: Huttner
authors.forename: Stefan
authors.initials: S
authors.lastname: Siebert
authors.forename: Christian
authors.initials: C
authors.lastname: Schwark
authors.forename: Peter A
authors.initials: PA
authors.lastname: Ringleb
authors.forename: Peter D
authors.initials: PD
authors.lastname: Schellinger
authors.forename: Werner
authors.initials: W
authors.lastname: Hacke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D020521:Stroke / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology*; D015912:Thrombolytic Therapy; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D010959:Tissue Plasminogen Activator