People with atrial fibrillation (AF) have distinctive biomarkers in their retinas, evident as early as four years before clinical presentation of the condition, confirms a new study published in PLOS Digital Health, led by Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology.
The research team analysed retinal imaging data from more than 90,000 people and discovered differences in the structure of the retina in people with AF, compared with those who do not have the condition.
AF, the most common heart rhythm disorder, affects more than 1.5 million people in the UK, and substantially raises the risk of stroke, heart failure and death. Because AF often occurs intermittently, it can be missed on a standard electrocardiogram (ECG), so many cases remain undiagnosed until a serious or life-threatening complication occurs.
Moorfields patient John Brewer first discovered he had AF in the operating theatre, while undergoing a cataract operation under sedation, earlier this year. The surgical team noticed John was experiencing heart arrhythmia and paused the procedure to hook up an ECG, which indicated that John did have AF. Medication was then provided so the operation could be safely completed. John was given an immediate referral to see a cardiologist who has since confirmed the AF diagnosis.
John said “It would have been so much easier if my AF had been detected earlier through a routine retinal scan, rather than on the operating table, which was a very distressing experience.”
The Moorfields team set out to establish whether retinal imaging, already used routinely in community optometry practices and hospital eye clinics, could offer a non-invasive way to flag people with AF before they have a stroke or heart attack.
It would have been so much easier if my AF had been detected earlier... rather than on the operating table
Researchers analysed optical coherence tomography (OCT) scans and colour retinal photographs from two datasets. In the AlzEye dataset, a Moorfields cohort with over 50,000 patients, 5,735 already had AF. In the UK Biobank cohort of around 40,000 participants, 526 had AF. Across both, people with AF consistently had thinner macular ganglion cells and inner plexiform layer (mGCIPL), a retinal layer at the back of the eye made up of nerve cells that connect the eye to the brain.
The thinner this layer was, the more likely the person was to be diagnosed with AF.
Patients who did not have AF when their retinal images were taken, but went on to develop AF, had thinner mGCIPL layers on average four years before presenting to hospital with the condition, even after accounting for age, sex, ethnicity, hypertension, diabetes, smoking and alcohol use. This indicates that retinal changes may be detectable before a clinical diagnosis of AF is made, at a stage when the condition has no symptoms.
The authors propose that the thinning they observed in people who developed or had AF could indicate mini strokes in the brain that typically occur as a result of AF before its diagnosis. The thinning could happen because blood flow to the retinal nerve cells is reduced by these strokes, they say.
Layers marked in yellow and red are those that indicate AF propensity
Senior author Siegfried Wagner said: “For patients, the value of this kind of eye imaging is that it is easy to access, quick and doesn't involve any invasive procedures. Although not intended to replace ECG-based diagnosis, retinal imaging could act as a complementary tool, catching those most at risk of AF before it causes real harm.”
Lead author Josef Huemer said: “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.”
Our findings raise the possibility that routine eye examinations could, in future, help identify people who would benefit from closer cardiac assessment
This study adds to growing evidence that high-resolution images of the eye can be used for early detection of systemic disease, a scientific field known as oculomics. The Moorfields team has been able to identify early signs and predict progression risk of eye conditions including AMD, glaucoma and diabetic retinopathy. The same team has also found markers for Parkinson’s disease, Alzheimer’s disease, schizophrenia, cardiovascular disease and stroke.
Oculomics has been made possible by the INSIGHT Eye and Oculomics Health Data Research Hub at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, the world’s largest ophthalmic imaging bioresource, with over 30 million eye images linked to medical records.
16 September 2026