THROMBOLYTIC THERAPY IN ACUTE ISCHEMIC STROKE - DO THE BENEFITS OUTWEIGH THE RISKS

There is a body of experimental and anecdotal evidence to suggest that thrombolytic therapy may be useful in reducing morbidity and mortalit y after acute ischaemic stroke. A series of clinical trials designed t o test hypotheses concerning risk and benefit have now been published. Intravenous streptokinase when given within 6 hours of ischaemic stro ke may be of marginal benefit when given alone, but of no benefit when given with aspirin (acetylsalicylic acid) because of an unacceptably high early mortality. There is a trend toward much better outcomes if streptokinase is given early (<3 hours post-stroke). Intravenous altep lase (tissue plasminogen activator; tPA) has a much better risk-benefi t profile than streptokinase, particularly when given within 3 hours o f a stroke at a dose of 0.9 mg/kg. Indeed, this dose was recently appr oved for use by the US Food and Drug Administration. Any planned admin istration of thrombolytic therapy to patients with acute ischaemic str oke should be in centres with experienced staff and facilities to moni tor clinical progress. Further trials are needed to identify which thr ombolytic agents, time windows of administration and dosages provide t he best risk-benefit ratios.