A new study has suggested that one of the most common forms of stroke may not mainly be caused by blocked arteries, challenging long-held beliefs about stroke prevention and treatment.
Researchers found that lacunar stroke, a type of ischemic stroke that affects small blood vessels deep within the brain, was more strongly linked to widening and damage of small brain arteries rather than narrowing of larger arteries.
The findings may change how doctors understand and treat cerebral small vessel disease, a condition connected to memory problems, silent strokes, and cognitive decline.
Lacunar strokes occur when blood flow to deep parts of the brain becomes disrupted due to damage in tiny blood vessels. They account for a significant portion of ischemic strokes, which are the most common type of stroke worldwide.
Traditionally, stroke prevention has focused on reducing fatty buildup and narrowing in major arteries through medications such as blood thinners, cholesterol-lowering drugs, and blood pressure treatments.
However, the new research found little connection between narrowed large arteries and lacunar stroke.
The study examined data from 229 stroke patients, including individuals who had experienced lacunar strokes and others with different mild stroke types. Researchers used MRI brain scans and clinical assessments to monitor changes in blood vessels over time.
Results showed that patients with widening and stretching of small arteries inside the brain were significantly more likely to have suffered lacunar strokes. These changes were also strongly linked to cerebral small vessel disease and an increased risk of silent strokes.
Silent strokes are small areas of brain damage caused by reduced blood supply that often develop without noticeable symptoms.
Researchers observed that more than one-quarter of participants experienced silent strokes within a year, despite receiving standard stroke prevention treatments.
The study suggests that current approaches focused mainly on preventing artery blockage may not fully address the underlying causes of lacunar stroke.
Scientists believe the widening of blood vessels may weaken their ability to properly control blood flow, potentially damaging delicate brain tissues over time.
The findings have increased interest in treatments aimed at improving the health and function of small blood vessels inside the brain rather than only targeting clogged arteries.
Researchers are now continuing investigations into medications that may help protect small brain vessels and reduce the risk of future strokes and cognitive decline.
Although the results are promising, experts say larger studies involving more diverse populations will be needed before major treatment guidelines can change.