AF-B-STEP: A global effort to transform atrial fibrillation detection and treatment

Key takeaways:

• New international research project AF-B-STEP will for the first time systematically assess how much time individuals spend in atrial fibrillation (AF) - their AF burden - and determine how this burden affects risks such as stroke, heart failure, and overall quality of life.
• The project will develop uniform standards for how medical devices and consumer technologies from implantable monitors to smartwatches detect and quantify AF and its burden.
• Eighteen partners from Europe and Canada have joined forces in this initiative to fundamentally improve the diagnosis and care of people with AF.

Amsterdam, 4 February 2026: An international research consortium has launched AF-B-STEP, a four-year research project designed to improve how atrial fibrillation (AF) is detected, quantified, and treated worldwide. AF-B-STEP brings together 18 partners from Europe and Canada with the collective goal of developing reliable, standardised methods to measure AF burden, the amount of time an individual spends in atrial fibrillation, and to understand how this influences stroke risk, heart failure, and patients' daily lives.

"The results are intended to help physicians make more precise decisions about who needs which treatment based on the AF burden. The goal of AF-B-STEP is to contribute to a measurable reduction in strokes and heart failure in the long term, while simultaneously avoiding unnecessary treatments in people with a low atrial fibrillation burden," says Prof. Dr. Paulus Kirchhof, Director of the Department of Cardiology at the University Medical Center Hamburg Eppendorf (UKE) and coordinator of the AF-B-STEP project.

Atrial fibrillation is the most common sustained cardiac arrhythmia globally and a leading cause of stroke and heart failure. It affects around one third of people over age 55 and accounts for up to three percent of healthcare spending in Europe and North America.

"For too long, atrial fibrillation has been treated as a simple 'yes or no' condition. AF-B-STEP has the potential to change clinical practice by linking AF burden to meaningful outcomes such as stroke and heart failure, ultimately improving care for millions of patients worldwide," says Prof. Helmut Pürerfellner, President of the European Heart Rhythm Association (EHRA), an AF-B-STEP partner and a branch of the European Society of Cardiology.

The project begins by assembling and analysing anonymised real-world data from more than 100,000 patients worldwide. By linking AF burden to outcomes such as stroke, heart failure, cardiovascular death, quality of life, and cognitive and cardiac function, the consortium aims to precisely quantify how AF burden drives clinical risk.

At the same time, AF-B-STEP partners, including manufacturers of implantable cardiac devices and wearable technologies, such as smartwatches and fitness trackers, will develop standardised methods for recording and presenting AF burden.

The goal is to create clear burden categories:

• Low AF burden - no further investigations or therapy required
• Moderate AF burden - additional diagnostic evaluation needed
• High AF burden - immediate initiation of anticoagulation and rhythm control therapy

This approach is expected to enable better patient stratification, support future treatment guidelines, and strengthen the role of AF burden in clinical decision making.

"By addressing the unmet needs in atrial fibrillation management, this large, concerted collaboration will be foundational to help guide future efforts to improve the management of AF globally," said Mirko De Melis, Distinguished Clinical Research Advisor at Medtronic Bakken Research Center in Maastricht, The Netherlands, which serves as industry lead for the project.

AF-B-STEP is funded with approximately €18 million from the Innovative Health Initiative (IHI), with contributions from both the European Union and industry partners.

ENDS