Patients with lacunar infarcts who reach hospital within 4.5 hours of onset will probably do as well with alteplase as people with other types of ischaemic stroke, a post-hoc trial analysis suggests.

There has been debate about whether lacunar infarcts — subcortical rounded, ovoid or tubular lesions (<20mm diameter) in regions supplied by penetrating arteries — will respond to thrombolysis, because the pathology of these infarcts is unclear.

Now an exploratory analysis of data from the WAKE-UP trial, which included 503 ischaemic stroke patients, suggests that clot-dissolving treatment is effective for lacunar strokes too, although the study was not sufficiently powered to be definitive.

The study found 59% of 55 patients with lacunar infarct, diagnosed using MRI, who received IV alteplase 4-5 hours post-event achieved the primary trial outcome (a score of 0-1 on the modified Rankin scale at 90 days).