Early Treatment of Ischemic Stroke With Intravenous tPA Reduces Disability Risk
Authors: Mike Mitka
Journal: JAMA (2013)

Very early treatment with intravenous thrombolysis forpatientswith mild-to-moderate acute ischemic strokes was associated with decreased risk ofhavingpermanentdisability, according to a European study published August 22 in Stroke. The American Heart Association/ AmericanStrokeAssociation(AHA/ASA)recommends getting patients to a hospital as soon as possible after onset of acute ischemic stroke symptoms for treatmentwith intravenous tissue-type plasminogen activator (tPA) This thrombolytic agent allows reperfusionof thebrainandhasprovenbenefit for select patients. AHA/ASAguidelines recommend giving tPA to treat stroke up to 4.5 hours after onset of symptoms. But sooner is farbetter than laterbecausestroke rapidlycauses irreversibly injuredtissue,with 2 million additional neurons lost each minute until reperfusion is achieved. In the Stroke study (Strbian D et al. Stroke. doi:10.1161/STROKEAHA.111.000819 [published online August 22, 2013]), researchers collected data from 6856 consecutive patients treated at 10 European strokecentersbetween 1998and2012.The patients, all of whom received tPA treatment (somewithin90minutesof strokeonset, some more than 90 minutes after onset of stroke symptoms), were divided into groups based on stroke severity as determined by the National Institutes of Health Stroke Scale (0-6, 7-12, and more than 12, designatingmild,moderate, and severe, respectively). The researchers found that for those with moderate stroke, receiving tPA in 90 minutes or less was associated with a 37% increased chance of having an excellent outcome at 3 months after stroke compared with receiving tPA after more than 90 minutes. An excellent outcome was defined as a score of 0 or 1 on the modified Rankin scale, which measures the degrees of disabil ity or dependence in daily activities after a stroke; a 0 or 1 means no symptoms of stroke or no significant disability. For patients with severe or mild stroke, the quick administration of tPA was not associated with improved chances of an excellent outcome. The researchers speculated that for those with mild stroke, quick administration of tPA did not improve the chances of an excellent outcome because the likelihood of disability is already very low. Secondary analysis did find an association at 3 months after stroke between patients receiving tPA in 90 minutes or less and a chanceofscoringa0onthemodifiedRankin scale. “Ultra-earlytreatment increasesthe likelihoodofexcellentoutcomes inpatientswith moderately severe symptoms and, in secondary analysis, also in those with mild symptoms,” said leadauthorDaniel Strbian, MD, PhD, from the department of neurologyatHelsinkiUniversityCentralHospital in Finland, in a release. “All measures must be taken to reduceonset-to-treatment timeas much as possible.” The Stroke study adds to the scientific literaturesupportingquicker treatmentof ischemicstrokewith tPA.Forexample,astudy in June involving 58 353 patients treated with tPA within 4.5 hours of symptom onset found faster treatment (measured in 15minute increments)was associatedwith reductions in in-hospital death and symptomatic intracranial bleeding and increased ratesof independent ambulationat discharge and discharge to home (Saver JL et al. JAMA. 2013;309[23]:2480-2488). For Larry B. Goldstein, MD, director of the Duke Comprehensive Stroke Center in Durham,NorthCarolina, theStroke studyaffirms existing thinking on treating acute ischemic stroke. “The trial is consistentwith our current practice, which is to try to treat patients as quickly as possible,” said Goldstein, who is also a spokesperson for the AHA/ASA. He also cautioned against interpreting the study’s findings too broadly. “One has to be careful of overinterpreting the results with consideration of stroke severity,” said Goldstein. “It is not a prospective randomized trial. It is a comparison of patients treated earlier or later,with treatment earlier seeming to benefit compared to treating later.” news@JAMA