Validating left atrial fractionation and low-voltage substrate during atrial fibrillation and sinus rhythm - a high-density mapping study in persistent atrial fibrillation

Abstract: Background: Low-voltage-substrate (LVS)-guided ablation for persistent atrial fibrillation (AF) has been described either in sinus rhythm (SR) or AF. Prolonged fractionated potentials (PFPs) may represent arrhythmogenic slow conduction substrate and potentially co-localize with LVS. We assess the spatial correlation of PFP identified in AF (PFP-AF) to those mapped in SR (PFP-SR). We further report the relationship between LVS and PFPs when mapped in AF or SR.

Materials and methods: Thirty-eight patients with ablation naïve persistent AF underwent left atrial (LA) high—density mapping in AF and SR prior to catheter ablation. Areas presenting PFP-AF and PFP-SR were annotated during mapping on the LA geometry. Low-voltage areas (LVA) were quantified using a bipolar threshold of 0.5 mV during both AF and SR mapping. Concordance of fractionated potentials (CFP) (defined as the presence of PFPs in both rhythms within a radius of 6 mm) was quantified. Spatial distribution and correlation of PFP and CFP with LVA were assessed. The predictors for CFP were determined.

Results: PFPs displayed low voltages both during AF (median 0.30 mV (Q1–Q3: 0.20–0.50 mV) and SR (median 0.35 mV (Q1–Q3: 0.20–0.56 mV). The duration of PFP-SR was measured at 61 ms (Q1–Q3: 51–76 ms). During SR, most PFP-SRs (89.4 and 97.2%) were located within LVA (<0.5 mV and <1.0 mV, respectively). Areas presenting PFP occurred more frequently in AF than in SR (median: 9.5 vs. 8.0, p = 0.005). Both PFP-AF and PFP-SR were predominantly located at anterior LA (>40%), followed by posterior LA (>20%) and septal LA (>15%). The extent of LVA < 0.5 mV was more extensive in AF (median: 25.2% of LA surface, Q1–Q3:16.6–50.5%) than in SR (median: 12.3%, Q1–Q3: 4.7–29.4%, p = 0.001). CFP in both rhythms occurred in 80% of PFP-SR and 59% of PFP-AF (p = 0.008). Notably, CFP was positively correlated to the extent of LVA in SR (p = 0.004), but not with LVA in AF (p = 0.226). Additionally, the extent of LVA < 0.5 mV in SR was the only significant predictor for CFP, with an optimal threshold of 16% predicting high (>80%) fractionation concordance in AF and SR.

Conclusion: Substrate mapping in SR vs. AF reveals smaller areas of low voltage and fewer sites with PFP. PFP-SR are located within low-voltage areas in SR. There is a high degree of spatial agreement (80%) between PFP-AF and PFP-SR in patients with moderate LVA in SR (>16% of LA surface). These findings should be considered when substrate-based ablation strategies are applied in patients with the left atrial low-voltage substrate with recurrent persistent AF

Object Details

• Location: Deutsche Nationalbibliothek Frankfurt am Main
• Extent: Online-Ressource
• Language: Englisch
• Notes: Frontiers in cardiovascular medicine. - 9 (2022) , 1000027, ISSN: 2297-055X

Contributors, Places and Time

• Event: Veröffentlichung
• (where): Freiburg
• (who): Universität
• (when): 2022
• Creator: Huang, Taiyuan ; Chen, Juan ; Müller-Edenborn, Björn ; Mayer, Louisa ; Eichenlaub, Martin ; Moreno-Weidmann, Zoraida ; Allgeier, Hans Jürgen ; Bohnen, Marius ; Lehrmann, Heiko ; Trenk, Dietmar ; Schöchlin, Simon ; Westermann, Dirk ; Arentz, Thomas ; Jadidi, Amir S.

Further information

• DOI: 10.3389/fcvm.2022.1000027
• URN: urn:nbn:de:bsz:25-freidok-2308346
• Rights: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Last update: 25.03.2025, 1:55 PM CET