Comparing lenient and strict heart rate control for atrial fibrillation

Lenient Rate Control Versus Strict Rate Control for Atrial Fibrillation. The Danish Atrial Fibrillation (DanAF) Randomised Clinical Trial

Not applicable Interventional Holbaek Sygehus · NCT04542785

This study tests whether a more relaxed or stricter way of controlling heart rate helps people with atrial fibrillation feel better and manage their condition more effectively.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment350 (estimated)
Ages18 Years and up
SexAll
SponsorHolbaek Sygehus Academic / other
Locations4 sites (Holbæk and 3 other locations)
Trial IDNCT04542785 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effects of lenient versus strict rate control strategies in patients with atrial fibrillation, a common heart arrhythmia. Conducted at four hospitals in Denmark, the study aims to determine which approach is more effective in managing this condition. Participants will be randomly assigned to either the lenient or strict rate control group, with their heart rates monitored and managed accordingly. The trial seeks to provide clarity on the optimal management strategy for patients with persistent or permanent atrial fibrillation.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older with confirmed persistent or permanent atrial fibrillation who accept rate control as their primary management strategy.

Not a fit: Patients with an initial heart rate under 80 bpm at rest or those deemed unfit for randomization by their physician may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved management strategies for patients with atrial fibrillation, potentially enhancing their quality of life and reducing associated risks.

How similar studies have performed: Previous studies have shown varying results regarding rate control strategies in atrial fibrillation, making this trial a valuable addition to the existing literature.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Participants with atrial fibrillation (ECG confirmed and diagnosed by the treatment provider) who at inclusion have either persistent (defined as atrial fibrillation for more than 7days) or permanent atrial fibrillation (only rate control is considered going forward).
2. Rate control must be accepted as being the primary management strategy going forward. Consideration towards whether rhythm control is more appropriate must be considered, especially given the results of the Early treatment of Atrial fibrillation for Stroke prevention Trial (EAST).
3. Informed consent.
4. Adult (18 years or older).

Exclusion Criteria:

1. No informed consent.
2. Initial heart rate under 80 bpm at rest (assessed via ECG before randomisation).
3. Less than 3 weeks of anticoagulation with new oral anticoagulants or 4 weeks with efficient warfarin if indicated.
4. If the treating physician deems that the participant is not fit to be randomised into both groups based on an individual assessment. Such a decision will be made before randomisation by the treating physician. This can e.g. be participants dependent on a high ventricular rate to maintain a sufficient cardiac output. Such participants could be participants with heart failure, participants with a hemodynamically significant valve dysfunction, or severely dehydrated participants.
5. Participants who are haemodynamically unstable and therefore require immediate electrical cardioversion

Where this trial is running

Holbæk and 3 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Atrial Fibrillation, PersistentAtrial Fibrillation ChronicAtrial FibrillationRate control
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.