Giving tPA to stroke patients within 6hrs of symptom onset does not improve mortality or independence at 6 months. However, patients might be a little “less disabled” while they are alive. Maybe.
Why It’s Important for Emergency Medicine
This is perhaps the most controversial article of 2012, call it thrombolytics-gate. As the body of research on thrombolysis in acute stroke gets scrutinized closer, more and more ED physicians are questioning the purported benefits of tPA. IST-3 is the biggest study of them all, enrolling over 3000 patients of all ages and stroke severities, but does little to clear up the confusion.
See for yourself below...
Major Points
- No difference in number of patients alive and independent @ 6 months
- Patients who got tPA at < 3 hrs did well, between 3-4.5 hrs did worse, between 4.5-6 hrs did well again - this randomness argues against time making a difference.
- Secondary analysis suggests that though patients treated with tPA did not live longer or independently, they did survive with less disability.
- Unblinded RCT, 3035 patients (age>80 years old = 53%)
- 156 hospitals, 12 countries, 11 years
Criticisms
- The evidence that treatment patients survived with less disability was found through ordinal analysis and statistical adjustment - whatever that means...
- Only patients in whom the benefit of tPA was “uncertain” but “promising” were included.
Reference
IST-3 collaborative group, Sandercock P, Wardlaw JM, Lindley RI, Dennis M, Cohen G, Murray G, Innes K, Venables G, Czlonkowska A, Kobayashi A, Ricci S, Murray V, Berge E, Slot KB, Hankey GJ, Correia M, Peeters A, Matz K, Lyrer P, Gubitz G, Phillips SJ, Arauz A. The benefits and harms of intravenous thrombolysis with recombinant tissue plasminogen activator within 6 h of acute ischaemic stroke (the third international stroke trial [IST-3]): a randomised controlled trial. Lancet. 2012 Jun 23;379(9834):2352-63. Pubmed
MIA 2012 = Most Interesting Articles series of 2012