Eye scans detect signs of atrial fibrillation years before diagnosis

People with atrial fibrillation have signs of the condition in the retinas of their eyes that can be detected as early as four years before diagnosis, finds a new study led by University College London (UCL) and Moorfields researchers.

The authors of the PLOS Digital Health paper analysed retinal imaging data from more than 90,000 people and discovered differences in the structure of the retina in people with atrial fibrillation, compared with those who do not have the condition.

Atrial fibrillation, 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 atrial fibrillation often occurs intermittently, it can be missed on a standard electrocardiogram (ECG). As a consequence, many cases remain undiagnosed until a serious or life-threatening complication occurs.

The 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 atrial fibrillation before they have a stroke or heart attack.

Researchers analysed optical coherence tomography (OCT) scans and colour retinal photographs from two datasets. In the AlzEye dataset, a Moorfields Eye Hospital cohort with over 50,000 patients, 5,735 already had atrial fibrillation. In the UK Biobank cohort of around 40,000 participants, 526 had atrial fibrillation. Across both datasets, people with atrial fibrillation consistently had thinner macular ganglion cells and inner plexiform layer (mGCIPL), which is a retinal layer at the back of the eye made up of nerve cells that connect the eye to the brain. The thinner this particular layer was, the more likely the person was to be diagnosed with atrial fibrillation.

Notably, among patients who did not have atrial fibrillation when their retinal images were taken, those who went on to develop atrial fibrillation 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 atrial fibrillation 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 atrial fibrillation could indicate mini strokes in the brain that typically occur as a result of atrial fibrillation before its diagnosis. The thinning could happen because blood flow to the retinal nerve cells is reduced by these strokes, they say.

Dr. Siegfried Wagner, senior author, UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation TrustThis large-scale analysis shows that retinal imaging can pick up on structural changes within the eye that are clearly linked to atrial fibrillation. 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 atrial fibrillation before it causes real harm."

John's story

Moorfields patient John Brewer first discovered he had atrial fibrillation 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 atrial fibrillation. 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 atrial fibrillation diagnosis.

John said: "It would have been so much easier if my atrial fibrillation had been detected earlier through a routine retinal scan at one of my regular appointments, rather than on the operating table, which was a very distressing experience for my wife and I."

Oculomics: Eye tests predicting systemic disease

Lead author Dr Josef Huemer (UCL Institute of Ophthalmology and Moorfields Eye Hospital NHS Foundation Trust) commented: "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."

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 UCL and Moorfields team has been able to identify early signs and predict progression risk of eye conditions including age-related macular degeneration (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.

Source:

University College London

Journal reference:

Huemer, J., et al. (2026). Atrial fibrillation and retinal imaging-based oculomics: A cross-sectional and longitudinal analysis of two large cohorts. PLOS Digital Health. DOI: 10.1371/journal.pdig.0001661. https://journals.plos.org/digitalhealth/article?id=10.1371/journal.pdig.0001661