Severe ischemic stroke: too severe for thrombolysis?

Twenty years after the introduction of IV thrombolysis with recombinant tissue plasminogen activator (rtPA), only a small proportion of stroke patients are treated with rtPA.(1) The strict inclusion and exclusion criteria in the stroke guidelines, based on criteria used in the rtPA trials, partially explains the low number of treated patients. Fear of intracranial hemorrhage after rtPA also drives the strict selection of patients, despite evidence of the safety and potential effectiveness of rtPA treatment in an off-label setting.(2,3) According to the European Medicines Agency, very severe stroke, defined as an NIH Stroke Scale (NIHSS) score of more than 25 points, represents a contraindication for rtPA.(4) The American Heart Association Stroke Council recommends an upper NIHSS score limit of 25 for patients presenting between 3 and 4.5 hours of stroke onset.(5) Japanese guidelines discourage the use of rtPA when the NIHSS score is above 23 points.(6