HMN 2025: How Home-based heart rhythm screening improves diagnosis of common heart condition

A wearable electrocardiogram (ECG) patch increases diagnosis of a common heart rhythm disorder, according to a study led by researchers at Oxford Population Health. The results of the Active Monitoring for Atrial Fibrillation (AMALFI) trial have been published in the American Heart Journal and were presented at the European Society of Cardiology Congress 2025.

Atrial fibrillation (AF) is a common but often undiagnosed heart rhythm disorder that substantially increases the risk of stroke and heart failure. Early detection of AF is important because it allows for timely treatment that can reduce stroke risk.

The AMALFI trial tested whether screening for AF using a simple wearable ECG patch could improve AF detection in participants aged 65 and over with known stroke risk factors. It included 5,040 participants. Half were randomly assigned to wear the iRhythm Zio XT monitor for two weeks in addition to their usual medical care, while the other half continued to receive their usual care without wearing a patch.

Participants were followed for 2.5 years to assess whether the patch resulted in more and earlier AF diagnosis and whether this affected prescription of blood-thinning medication (anticoagulants).

Key findings:

• 172 study participants (6.8%) who received a patch were diagnosed with AF compared to 136 (5.4%) of those who received usual medical care only (a modest but statistically significant difference).
• Participants who received a patch were diagnosed with AF earlier (median 103 days versus 530 days in the control group).
• Participants who received a patch were more likely to be prescribed anticoagulants, with an average of 1.63 months’ exposure over the study period, compared to 1.14 months in the control group.
• In over half of the 89 participants whose AF was detected by the patch, it was found on the first day of monitoring.
• In 49 cases (55%) the AF detected by the patch was only present for part of the time (low burden) with under 10% of monitored time spent in AF.
• The observed rate of stroke was similar between groups: 2.7% in the screening group and 2.5% in the control group, but AMALFI was not designed to study direct effects on stroke.

Dr. Rohan Wijesurendra, Senior Clinical Research Fellow at Oxford Population Health, Consultant Cardiologist and Electrophysiologist, and lead author of the study, said “Our study shows that remote screening using ECG patches can modestly increase detection of AF and treatment with anticoagulants in older individuals at increased risk of stroke. However, the clinical benefit may be limited by the low burden of AF in many of those identified.

“We need more research to understand whether looking for AF in this way helps to prevent strokes—and whether it’s cost-effective.”

AMALFI was an entirely remote study, with no physical study sites or in-person visits. Participants were identified via an automated search of electronic records in participating GP practices. The iRhythm ZioXT long-term continuous monitoring (LTCM) devices used in this study were mailed directly to the participants in the intervention group.

The monitoring devices were self-applied, recorded the participants’ ECG heart rhythm data continuously for 14 days while they went about their normal day-to-day activities, and were then returned for analysis, technician review, and interpretation by a cardiologist. The results were then sent to the participants’ GPs.

Louise Bowman, Professor of Medicine and Clinical Trials at Oxford Population Health, and a senior author of the paper, said “AF can be difficult to detect as it often occurs without symptoms and/or infrequently. New monitoring technology has enabled longer-duration screening which can detect short or infrequent AF episodes which might otherwise be missed.

“AMALFI has shown that it is possible to undertake screening for AF efficiently and with minimal disruption to practice staff and participants, demonstrating that remote clinical trials can assess important health questions. Longer-term and cost-effectiveness analyses of AMALFI are planned and will provide more insight in due course.”

Dr. Sonya Babu-Narayan, Clinical Director at the British Heart Foundation and consultant cardiologist, said “In this study, researchers found that at-home screening for atrial fibrillation, using easy-to-apply ECG patches that can be returned by mail, was practical and convenient for older patients, including those living with multiple health conditions. More research is now needed to better understand who may benefit from this type of screening.”

“This large, randomized trial builds on a large clinical evidence base that demonstrates the effectiveness of our patch-based long-term continuous monitoring for early detection of atrial fibrillation, but in an even higher risk population than in previous trials,” said Mintu Turakhia MD MS, Chief Medical & Scientific Officer of iRhythm Technologies.

“What is unique and impressive about this trial is that it enrolled from over two dozen UK primary care centers in the National Health Service and used a home-based approach—participants did not have to come into the clinic or the hospital to receive screening.

“This trial validates the effectiveness of this approach in the UK, which is important because early, appropriate treatment of AF can prevent stroke, heart failure, hospitalization, improve quality of life, and reduce health care expenditures.”

Provided by
Oxford Population Health