No subgroup of minor stroke was rescued by looking at the occlusion

Design

prespecified secondary subgroup analysis of a randomised, controlled, blinded trial

Population

881 patients with minor ischaemic stroke (NIHSS ≤5) and intracranial occlusion or focal perfusion abnormality within 12 hours

Primary outcome

return to pre-stroke neurological functioning or better at 90 days (mRS)

Effect

adjusted RR 1.03 (0.90–1.18) no visible occlusion; 0.85 (0.71–1.01) near occlusion; 1.00 (0.89–1.12) complete occlusion

TEMPO-2 had already shown that patients with minor ischaemic stroke — NIHSS of 5 or less — with an intracranial occlusion or focal perfusion abnormality within 12 hours did not benefit from intravenous tenecteplase against non-thrombolytic standard care. The obvious next question was whether the occlusion itself picks out a group who do.

This secondary analysis divided the 881 patients into three strata by revised arterial occlusive lesion score: complete occlusion (218 control, 216 tenecteplase), near occlusion (102 and 92) and no visible occlusion with a focal perfusion abnormality (130 and 123). The outcome was return to pre-stroke neurological function or better at 90 days, adjusted for age, sex, onset-to-randomisation time and baseline severity.

Nothing separated. Adjusted risk ratios were 1.03 (95% CI 0.90 to 1.18) with no visible occlusion, 0.85 (0.71 to 1.01) with near occlusion and 1.00 (0.89 to 1.12) with complete occlusion. The near-occlusion estimate, if anything, points the wrong way. Baseline imbalances existed — longer delays in the control arm with near occlusion, and older, more hypertensive patients with higher creatinine in the tenecteplase arm with complete occlusion — which is worth knowing when reading the point estimates, but does not rescue a benefit that is not there.

• Do not use the presence of an occlusion to justify thrombolysis in NIHSS ≤5 stroke
• Keep antiplatelet secondary prevention as the default in minor stroke with proven occlusion
• Continue vessel imaging for diagnosis and for identifying thrombectomy candidates — the imaging is still needed
• Document the NIHSS at presentation, since the decision hinges on it

Why it matters

It closes the most plausible remaining route to thrombolysing minor strokes.

Don't overread it

A secondary subgroup analysis of a neutral trial cannot exclude a small benefit — it excludes a clinically useful one.

The statistics, in plain English

All three confidence intervals comfortably include 1.0, and they are reasonably narrow — this is an absence of effect rather than an inability to detect one. Subgroup analyses of a neutral trial are underpowered by construction, so a small benefit in one stratum cannot be excluded; what can be excluded is the large benefit that would justify changing practice. The baseline imbalances are what you would expect from chance across six groups.

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