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Updated: May 28, 2026
08:10
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Exercise heart rate acceleration patterns during atrial fibrillation and sinus rhythm
Jonathan Buber1, Michael Glikson, Michael Eldar
1Leviev Heart Center, Sheba Medical Center, Tel Hashomer, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. yonibuber@gmail.com
Summary
Patients with atrial fibrillation experience reduced exercise tolerance due to early heart rate peaking, even with adequate rate control. This pattern persists despite treatments, impacting overall physical performance.
Area of Science:
- Cardiology
- Exercise Physiology
Background:
- Patients with atrial fibrillation (AF) exhibit lower exercise tolerance than those in sinus rhythm, even with effective rate control.
- This reduced capacity persists despite interventions aimed at managing heart rate.
Purpose of the Study:
- To investigate exercise heart rate acceleration patterns in patients with atrial fibrillation.
- To determine if adequate rate control mitigates the impact of AF on exercise performance.
Main Methods:
- Exercise testing was conducted on 30 patients during atrial fibrillation and after cardioversion.
- Heart rate parameters and acceleration were analyzed during exercise stages.
- Patients maintaining sinus rhythm underwent a follow-up test after one month.
Main Results:
- Heart rate peaked significantly earlier and was higher during atrial fibrillation compared to sinus rhythm (p < 0.001).
- Total exercise duration was shorter in atrial fibrillation (6 min vs. 8.5 min, p < 0.001).
- Beta-blocker use did not alter the early heart rate peaking pattern.
Conclusions:
- Atrial fibrillation is associated with a distinct pattern of early exercise heart rate peaking.
- This early peaking contributes to reduced exercise tolerance, irrespective of resting heart rate control.
- Restoring sinus rhythm improves exercise performance parameters.
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