Thrombolysis for acute ischaemic stroke works

EDITOR—We disagree with the thrust of Gubitz and Sandercock's interpretation of the evidence for treatment of acute ischaemic stroke.1 The meta-analysis that they quote includes three different thrombolytic agents, different time windows, and different doses.2 There may be no statistical evidence of heterogeneity of treatment effect, but there are clinical grounds to believe that these factors make for critically important differences.

In the same meta-analysis the more homogeneous data drawn from the three trials that treated patients with intravenous alteplase within three hours of onset are also reported. A major treatment effect is observed, with an odds ratio of 0.55 (95% confidence interval 0.42 to 0.72) in favour of treatment. These patients include those who had early intracerebral haemorrhage. In this 0–3 hour group there is no increased mortality.

The same analysis for the streptokinase trials shows no benefit but is impaired by the small numbers of patients …