Researchers estimate that about 52.55 million people around the world are living with atrial fibrillation (AFib) — a cardiovascular condition where the beating of the upper and lower champers of the heart are out of sync, causing a “fluttering” or racing heartbeat.
People with AFib are at an increased risk for several health issues, including stroke, heart failure, heart attack, and dementia.
In many cases, AFib doesn’t have any noticeable symptoms or has symptoms shared with other common issues. For this reason, it’s not uncommon for AFib to go undetected until it becomes a problem.
A recent study found that about 62% of people with AFib didn’t realize they had it before being diagnosed.
Now, a new study published in the journal PLOS Digital Health presents evidence suggesting certain changes to the eye’s retina, or layer of cells in the back of the eye, may help detect AFib as early as 4 years before diagnosis.
For this study, researchers analyzed optical coherence tomography (OCT) scans of the retina and color retinal photography for more than 90,000 people. The images were found through two large cohort studies — AlzEye and the U.K. Biobank.
“The retina is the only place in the body where blood vessels and nerve fiber tissue can be analyzed noninvasively with commonly available eye tests like OCT scans or fundus photographs,” Josef Huemer, MD, consultant ophthalmologist at Moorfields Eye Hospital and honorary senior research fellow at the Institute of Ophthalmology University College London, and lead author of this study, told Medical News Today.
Huemer explained:
“In previous work on retinal strokes we found a very strong signal for ocular events in patients with AFib, and further work has shown that diseases like Parkinson’s disease, or even schizophrenia would cause subtle retinal changes — in the case of Parkinson’s disease several years prior to the disease manifestation.”
FC JSS 18-Sep-26. Please link to the previous work mentioned above (I am having a hard time finding it on a quick search).
At the study’s conclusion, researchers found that people with AFib consistently had a thinner macular ganglion cells and inner plexiform layer (mGCIPL).
This layer combines two different layers in the retina, the ganglion cell layer that relays visual information from the retina and the brain, and the inner plexiform layer, which sends to the brain info on certain visual signals like motion and changes between light and dark.
“Thinning of the mGCIPL is a sign of retrograde, or past, degeneration, and is therefore not disease specific,” Huemer explained.
“It is most likely caused by mini strokes in the brain, a common finding in patients with AFib. However, this finding was identified in both cohorts, one of hospital-based patients and one in a healthy volunteer study, which gives us confidence in the findings,” he detailed.
“Furthermore, we found thinning of the inner nuclear layer, which is not caused by retrograde degeneration, and our hypothesis is that this thinning is caused by cardiovascular disease, as this area is very vulnerable to micro strokes of the eye,” he added.
Heumer and his team also found that among study participants who did not originally have AFib when their retinal photos were taken, those who eventually developed AFib had thinner mGCIPL layers on average 4 years before presenting to hospital with the heart condition.
“This is indeed very interesting, it highlights several things,” Huemer told us. “Number one, the difficulty of establishing the diagnosis of AFib. Number two, this thinning can fairly easily be quantified by OCT scans that are widely available in primary care ophthalmology — for example at high street optometrists in the U.K.”
“The next step is to explore if this finding could also be used to improve risk calculation and to assess if we can identify patients earlier and refer them for long-term electrocardiogram monitoring,” he continued.
“We are currently working on more OCT-related image analysis in the context of cardiovascular disease in large scale datasets. We have also expanded our dataset to enable further oculomic research,” said Huemer.
“In the coming years we anticipate progressing our research algorithms in oculomics through the regulatory pathway for approval as a medical device, for use in local optometry settings for earlier detection of systemic disease,” he added.
When asked how a heart condition like AFib might be assessed through changes in retina eye cells, Huemer said the retina allows for unique, non-invasive assessment of blood vessels and nerve fiber layers.
“Furthermore, seeing is highly energy dependent, therefore the retinal vasculature is more susceptible to show cardiovascular damage in similar fashion to diabetic retinopathy. The connection of cardiovascular problems and subtle changes at the level of the retina is well established and was first mentioned in the late 1800s. With today´s imaging and AI supported segmentation algorithms, as well as advanced statistics, we can provide more robust evidence about these associations.”
– Josef Huemer, MD
MNT also spoke with Benjamin Bert, MD, a board-certified ophthalmologist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA, who was not involved in this study.
“Since atrial fibrillation can cause strokes, the hypothesis from the researchers is that there could be ‘silent ischemia’ — small episodes of poor blood perfusion causing damage to the tissues leading to thinning of these particular layers of the retina,” Bert detailed.
“They also hypothesize that it could be related to mild damage to the brain that then leads to cellular atrophy in the retina,” he added.
Finally, MNTalso had the opportunity to speak with Cheng-Han Chen, MD, a board-certified interventional cardiologist and medical director of the Structural Heart Program at MemorialCare Saddleback Medical Center in Laguna Hills, CA.
Chen, who likewise was not involved in this study, commented that a technique that could identify people at increased risk of developing AFib through routine eye imaging could potentially broaden our ability to recognize risk earlier and identify patients who may benefit from closer cardiovascular monitoring.
“The underlying mechanism linking AFib with changes in the cells or blood vessels of the eye is not yet well understood,” he explained. “We do not typically think of heart rhythm disorders as being directly associated with changes in eye cells, so this potential connection is particularly interesting and warrants further investigation.”
“Future studies will need to determine exactly what biological changes in the eye are associated with AFib and whether these changes can reliably predict who will go on to develop the condition,” Chen continued.
“Researchers will also need to determine how well eye imaging performs across different populations and whether it could ultimately become a practical screening tool. At this stage, these findings are promising but should be viewed as an early step toward understanding a potential connection between the heart and the eye,” he concluded.
