LAUSR

Introduction Branch atheromatous disease (BAD) contributes to small-vessel occlusion in cases of occlusion or stenosis of large calibre penetrating arteries, and it is associated with a higher possibility of early neurological deterioration (END) and recurrent stroke in acute ischaemic stroke. As the pathology of BAD is due to atherosclerosis, we postulate that early intensive medical treatment with dual antiplatelet therapy (DAPT) and high-intensity statins may prevent END and recurrent stroke in acute small subcortical infarction caused by BAD. Methods and analysis In this prospective, single-centre, open-label, non-randomised, single-arm study using a historical control, we will compare early DAPT and high-intensity statin treatment with a historical control group of patients with BAD who were treated with single antiplatelet therapy without high-intensity statin treatment. Patients will be eligible for enrolment if they are admitted for acute ischaemic stroke within 24 hours, have a National Institutes of Health Stroke Scale (NIHSS) score of 1–8 and are diagnosed with BAD by MRI. Patients will take aspirin, clopidogrel and high-intensity statins (atorvastatin or rosuvastatin) within 24 hours of stroke onset, followed by aspirin or clopidogrel alone from day 22. The primary endpoint is the percentage of patients who develop END within 7 days of stroke onset (defined as an increase in the NIHSS score ≥2 points) and recurrent stroke within 30 days. The total sample sizes will be 138 for the intervention group and 277 for the control group. A historical control group will be drawn from previous prospective observation studies. Ethics and dissemination The protocol of this study has been approved by the Institutional Review Board of Chang Gung Memorial Hospital (202001386A3). All participants will have to sign and date an informed consent form. The findings arising from this study will be disseminated in peer-reviewed journals and academic conferences. Trial registration number NCT04824911.