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Updated: Nov 24, 2025
Estimating Bilateral Atrial Function by Cardiovascular Magnetic Resonance Feature Tracking in Patients with Paroxysmal Atrial Fibrillation
Published on: July 20, 2022
Conduction Heterogeneity: Impact of Underlying Heart Disease and Atrial Fibrillation
Annejet Heida1, Willemijn F B van der Does1, Lianne N van Staveren1
1Department of Cardiology, Erasmus Medical Center, Rotterdam, the Netherlands.
Insights
Underlying heart diseases do not affect atrial conduction heterogeneity. However, prior atrial fibrillation (AF) episodes are linked to more frequent and severe conduction slowing throughout the atria and Bachmann's bundle.
Area of Science:
- Cardiology
- Electrophysiology
- Cardiac Surgery
Background:
- Intra-atrial conduction during sinus rhythm in patients with underlying heart disease (UHD) and prior atrial fibrillation (AF) is not well understood.
- Investigating conduction differences based on UHD type and AF history is crucial for understanding AF pathophysiology.
Purpose of the Study:
- To investigate the impact of various underlying heart diseases (UHDs) and prior atrial fibrillation (AF) episodes on intra-atrial conduction heterogeneity during sinus rhythm.
- To determine if conduction patterns differ among patients with ischemic, valvular, or congenital heart disease.
- To assess the influence of previous AF episodes on conduction properties.
Main Methods:
- Epicardial mapping of the atria, Bachmann's bundle (BB), and pulmonary vein area was performed in 447 participants undergoing cardiac surgery.
- Conduction times (CTs) were measured to assess the frequency and magnitude of conduction disorders.
- Participants had various underlying heart diseases and some had a history of AF.
Main Results:
- No significant differences in conduction disorder frequency or magnitude were observed among the three types of underlying heart disease.
- Prior AF episodes were associated with increased conduction slowing throughout both atria (14.9% vs. 12.8%).
- More severe conduction disorders (CTs ≥30 ms) at Bachmann's bundle were prevalent in patients with a history of AF (56.2% vs. 36.0%).
Conclusions:
- Underlying heart disease does not impact the frequency or severity of atrial conduction disorders.
- Previous episodes of atrial fibrillation are associated with more frequent and severe conduction abnormalities in both atria and Bachmann's bundle.
- Further research is needed to determine the clinical relevance of these conduction disorders in AF development and maintenance.
Objectives:
The goal of this study is to investigate the impact of various underlying heart diseases (UHDs) and prior atrial fibrillation (AF) episodes on conduction heterogeneity.
Background:
It is unknown whether intra-atrial conduction during sinus rhythm differs between various UHD or is influenced by AF episodes.
Methods:
Epicardial sinus rhythm mapping of the right atrium, Bachmann's bundle (BB), left atrium and pulmonary vein area was performed in 447 participants (median age: 67 [interquartile range (IQR): 59 to 73] years) with or without AF undergoing cardiac surgery for ischemic heart disease, (ischemic and) valvular heart disease, or congenital heart disease. Conduction times (CTs) were defined as Δ local activation time between 2 adjacent electrodes and used to assess frequency (CTs ≥ 4 ms) and magnitude of conduction disorders (in increments of 10 ms).
Results:
When comparing the 3 types of UHD, there were no differences in frequencies and magnitude of CTs at all locations (p ≥ 0.017 and p ≥ 0.005, respectively). Prior AF episodes were associated with conduction slowing throughout both atria (14.9% [IQR: 11.8 to 17.0] vs. 12.8% [IQR: 10.9 to 14.6]; p < 0.001). At BB, CTs with magnitudes ≥30 ms were more common in patients with AF (n = 56.2% vs. n = 36.0%; p < 0.004).
Conclusions:
UHD has no impact on the frequency and severity of conduction disorders. AF episodes are associated with more conduction disorders throughout both atria and with more severe conduction disorders at BB. The next step will be to determine the relevance of these conduction disorders for AF development and maintenance.
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