Study title: AMALFI: Active Monitoring for Atrial Fibrillation

Published in Congress: European Society of Cardiology (ESC) Congress, 2025

Link: https://www.escardio.org/The-ESC/Press-Office/Press-releases/Remote-atrial-fibrillation-screening-using-an-ECG-patch-demonstrates-modest-benefits

Prepared by: Dr. Özkan Karaca

Introduction
Atrial fibrillation (AF) affects more than 30 million people worldwide, increases the risk of stroke five-fold, and accounts for about one-third of ischemic strokes. Oral anticoagulation can substantially reduce stroke risk, yet AF often remains undiagnosed because it can be asymptomatic. Current guidelines note insufficient evidence on the role of AF screening in stroke prevention.

Objective

The AMALFI trial aimed to evaluate whether remote screening for asymptomatic AF using a continuous ambulatory ECG patch could increase detection rates and assess the feasibility of implementing this strategy in the healthcare system.

Methods

The trial enrolled individuals aged 65 years or older with CHA2DS2VASc scores ≥3 (men) or ≥4 (women), and no prior AF diagnosis. A total of 5,040 participants were randomized 1:1: the intervention group (n=2,520) received a 14-day Zio® XT patch monitor by mail, while the control group (n=2,520) received usual care. The primary endpoint was the detection of new AF within 2.5 years.

Results

At 2.5 years, AF was diagnosed in 6.8% of the intervention group (172/2520) compared with 5.4% in the control group (136/2520). This difference was statistically significant (Rate ratio: 1.26; 95% CI: 1.02–1.57; p=0.03). Time-to-diagnosis analyses also favored the intervention group (Rate ratio: 1.29; 95% CI: 1.03–1.61; p=0.03). Additional arrhythmias such as atrial flutter, advanced AV block, long pauses, and ventricular tachycardia were also detected in the intervention group. However, there was no significant difference in death or stroke outcomes between groups.

Conclusion

The AMALFI trial demonstrated that a simple, remote, and scalable screening strategy increased AF detection rates and was feasible in a high-risk population. Nevertheless, at 2.5 years, there was no significant difference in major clinical outcomes such as stroke. Ongoing long-term follow-up and health economic analyses will clarify the true clinical and economic impact of this strategy.

Comment

The AMALFI trial highlights an innovative and scalable approach to detecting asymptomatic AF. It underscores the growing role of digital health technologies in primary care. Although short-term impact on major outcomes appears limited, long-term results and cost-effectiveness analyses will be key in determining whether widespread adoption of this strategy is justified.