A routine eye scan may hold early clues about atrial fibrillation, a heart-rhythm problem that drives about one in seven strokes in the United States.
Researchers at University College London and Moorfields Eye Hospital reported the finding on September 10, 2026, in PLOS Digital Health after analyzing retinal images from more than 90,000 people.
Atrial fibrillation, or AFib, makes the upper chambers of the heart quiver rather than beat steadily. Blood can then pool and form clots.
That raises the stroke risk roughly fivefold, according to the Centers for Disease Control and Prevention. Many people notice nothing until a stroke or a routine check reveals the arrhythmia.
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What the retinal scan revealed
The team looked at two large groups. One was the AlzEye dataset, with 50,651 patients from Moorfields.
The other was the UK Biobank, with more than 39,000 participants who had no AFib when first scanned.
They focused on the macular ganglion cell and inner plexiform layer. That thin band of nerve tissue near the back of the eye carries signals from the retina toward the brain.
People already living with AFib had a thinner nerve layer than people without the condition. Participants who developed AFib later showed the same thinning before diagnosis. The mean time between the eye scan and diagnosis was 3.95 years.
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Each standard deviation drop in that layer was linked to a 27 percent higher hazard of developing AFib. The link held after accounting for age, sex, ethnicity, high blood pressure, diabetes, smoking, and alcohol use.
What might explain the link
The researchers propose that the eye is picking up damage from tiny, silent strokes that AFib can cause before symptoms appear.
Reduced blood flow to nerve cells in the retina may leave a lasting mark that modern scans can measure.
"This large-scale analysis shows that retinal imaging can pick up on structural changes within the eye that are clearly linked to atrial fibrillation," said Dr. Siegfried Wagner, senior author of the study at UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation Trust.
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Lead author Dr. Josef Huemer put the possible use plainly. "If confirmed in further research, our findings raise the possibility that routine eye examinations could, in future, help identify people who would benefit from closer cardiac assessment, potentially enabling earlier treatment with therapies known to reduce the risk of stroke," he said.
Why early detection matters
AFib often shows up as everyday fatigue, palpitations, or shortness of breath, but many people feel nothing at all. The CDC projects that 12.1 million people in the US will have AFib by 2050.
The condition already contributes to about 158,000 deaths a year in the country. Blood thinners can sharply lower stroke risk when doctors catch AFib in time.
The scan behind the finding is called optical coherence tomography, or OCT. It is already used at eye clinics to check for glaucoma and other conditions. No new equipment would be needed to look for these nerve changes.
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For now, the researchers call for further studies before eye scans are used to screen for heart-rhythm risk. Anyone worried about palpitations or unexplained fatigue should raise it with a family doctor.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.