Assessment of Predictors for Left Atrial Substrate Severity in Patients Undergoing Ablation for Persistent Atrial Fibrillation

By
Edoardo Cecchini
Gennaro Fabiano
Paola Liporace
Paolo Francesco Sorrenti
Giuseppe Campagna
Emmanuel Fabiano
Jacopo Colella
Alessandro Di Vilio
Giuseppe Indellicati
Simona Brogneri
Diego Sangiorgi
Andrea Petretta
Saverio Iacopino
July 6, 2026

Frontiers In Cardiovascular Medicine

Overview

This study evaluates predictors of left atrial substrate severity in patients with persistent atrial fibrillation undergoing catheter ablation. Key findings indicate that very low-voltage zones and specific atrial wall characteristics significantly correlate with recurrence rates post-ablation.

Background

Persistent atrial fibrillation (AF) presents unique challenges in ablation outcomes due to extensive left atrial (LA) remodeling. Understanding the predictors of LA substrate severity is crucial for tailoring ablation strategies to improve patient outcomes. This study aims to enhance the personalization of ablation procedures by identifying key substrate characteristics.

Data Highlights

Predictor	Hazard Ratio (HR)	p-value
Very low-voltage zones (<0.2 mV)	1.025	0.008
Posterior-wall EAT	0.267	0.007
Anterior-wall AF drivers	0.287	0.021
Very low bipolar voltage burden in the roof	1.024	0.026

Key Findings

Freedom from recurrence at 12 months was 70.6% among patients.
Higher mean percentage of very low-voltage zones predicted recurrences (HR 1.025; p = 0.008).
Posterior-wall epicardial adipose tissue (EAT) showed a protective effect against recurrence (HR 0.267; p = 0.007).
Anterior-wall AF drivers were also associated with reduced recurrence risk (HR 0.287; p = 0.021).
Very low bipolar voltage burden in the roof was linked to increased recurrence risk (HR 1.024; p = 0.026).

Clinical Implications

The identification of specific predictors of left atrial substrate severity can guide clinicians in personalizing ablation strategies for patients with persistent AF. Tailoring ablation procedures based on these predictors may enhance outcomes and reduce recurrence rates.

Conclusion

This study highlights the importance of characterizing left atrial substrate anomalies in persistent AF to improve ablation outcomes. Further research is warranted to validate these predictors in broader clinical settings.