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Published on: July 20, 2022
The relationship between electrogram cycle length and dominant frequency in patients with persistent atrial
Sheldon M Singh1, E Kevin Heist, Jacob S Koruth
1Heart Center, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
Insights
Complex fractionated atrial electrograms (CFAE) and high dominant frequency (DF) sites are ablation targets for persistent atrial fibrillation (AF). This study found a poor correlation between electrogram mean cycle length (MCL) and DF in AF patients, suggesting different ablation strategies may target distinct atrial regions.
Area of Science:
- Cardiac Electrophysiology
- Atrial Fibrillation Ablation
- Medical Device Technology
Background:
- Persistent atrial fibrillation (AF) management often involves catheter ablation.
- Complex fractionated atrial electrograms (CFAE) and high dominant frequency (DF) sites are proposed ablation targets.
- The relationship between CFAE-derived mean cycle length (MCL) and DF in persistent AF remains unclear.
Purpose of the Study:
- To investigate the correlation between electrogram mean cycle length (MCL) and dominant frequency (DF) in patients with persistent atrial fibrillation.
- To determine if these electrophysiological markers identify similar regions in the left atrium post-pulmonary vein isolation.
Main Methods:
- Analysis of 9,262 electrograms from 44 patients with persistent AF after pulmonary vein isolation.
- Electrograms were mapped using a multielectrode catheter throughout the left atrium.
- Mean cycle length (MCL) and dominant frequency (DF) were calculated using spectral analysis (fast Fourier transformation).
Main Results:
- A weak but statistically significant correlation (r = 0.21, P < 0.001) was observed between MCL and DF across all analyzed electrograms.
- Individual patient analysis revealed a poor correlation, with r values ranging from -0.18 to 0.47.
- Average MCL was 135 ± 24 ms and average DF was 6.1 ± 0.6 Hz post-pulmonary vein isolation.
Conclusions:
- There is a poor correlation between electrogram MCL and DF in patients with persistent AF.
- Ablation strategies targeting DF and CFAE are unlikely to focus on the same left atrial sites.
- Further comparative studies are needed to evaluate the efficacy of DF- versus CFAE-guided ablation for persistent AF.
Introduction:
Sites of complex fractionated atrial electrograms (CFAE) with a short mean cycle length (MCL) and sites with a high dominant frequency (DF) have been advocated as targets for ablation in patients with persistent atrial fibrillation (AF). However, there are little data on the relationship between theses 2 markers. This study assessed the relationship between the DF and electrogram MCL after pulmonary vein (PV) isolation in patients with persistent AF.
Methods And Results:
A total of 44 patients with persistent AF were studied. Four-second bipolar electrograms were obtained with a multielectrode mapping catheter at regions throughout the left atrium after isolation of the pulmonary veins, with analysis of the MCL and DF at each site. The DF was defined as the largest frequency peak within a 2.5- to 16-Hz spectral profile generated with fast Fourier transformation of the electrogram. A total of 9,262 electrograms from the 44 patients were analyzed. The average MCL and DF post-PV isolation were 135 +/- 24 ms and 6.1 +/- 0.6 Hz, respectively. There was a statistically significant but weak correlation between the MCL and DF (r = 0.21, P < 0.001). Additionally, analysis of this relationship within each patient did not demonstrate a strong correlation (range of r values per patient =-0.18 to 0.47).
Conclusions:
There is a poor correlation between the electrogram MCL and DF in patients with persistent AF. Ablation strategies targeting DF and those targeting CFAE are therefore unlikely to direct ablation toward similar left atrial sites. Comparative studies are necessary to determine the effectiveness of each strategy in guiding catheter ablation of persistent AF.
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