Rethinking what drives a common stroke type. New research published in Circulation reveals that lacunar stroke — responsible for up to 30% of ischemic strokes — is driven by arterial widening and small vessel disease in the brain, not fatty plaque buildup as long assumed. The finding helps explain why standard antiplatelet drugs like aspirin often fall short, and is already shaping new treatment trials targeting the brain's tiny blood vessels.
Rethinking what drives a common stroke type
For decades, doctors have treated lacunar stroke — a common form of ischemic stroke — much like other stroke types, assuming fatty plaque clogging larger arteries was the main culprit. But new research published in Circulation is challenging that assumption. Scientists from the University of Edinburgh and international collaborators found that arterial widening and elongation (known as dolichoectasia), not atherosclerotic blockage, is the dominant driver of lacunar stroke and the small vessel disease behind it.
The study followed 229 patients with recent lacunar or mild non-lacunar stroke, using MRI scans at baseline and one year later. Patients with enlarged basilar arteries were over four times more likely to have had a lacunar stroke, and showed faster progression of brain damage and more "silent" strokes — even while on standard preventive treatments.
Key Takeaways
Why it matters: These findings reframe lacunar stroke as a fundamentally different disease from other ischemic strokes — one that requires its own treatment strategy. Clinicians should continue following current guidelines while new microvascular-targeted therapies are evaluated in ongoing trials.
