# Impact of atrial functional substrate in patients with atrial fibrillation: The potential utility of decremental evoked potential mapping in the atrium

## TL;DR

This study explores how a technique called decremental evoked potential (DEEP) can help identify atrial functional substrates in patients with atrial fibrillation, potentially guiding ablation treatments.

## Contribution

The study is the first to investigate DEEP in the atrium and its association with clinical outcomes in atrial fibrillation.

## Key findings

- DEEP was more common in patients with persistent AF and higher brain natriuretic peptide levels.
- Patients with atrial DEEP had greater pericardial fat volume and more early AF recurrence after ablation.
- Atrial DEEP correlates with electrophysiological remodeling and could be a target for AF ablation.

## Abstract

Decremental evoked potential (DEEP) is one of the functional substrates mainly used in the field of ventricular arrhythmias, which is suggested to be a critical target of reentrant ventricular tachycardia.

The purpose of this study is to investigate the characteristics of patients with atrial functional substrates expressed by DEEP and their clinical significance.

Patients presenting for atrial fibrillation (AF) ablation from April 2023 to March 2024 at Tottori University Hospital were analyzed. After cryoballoon pulmonary vein isolation, DEEP was evaluated at the left atrial roof and posterior wall by extrastimulus pacing maneuvers. To verify the clinical significance of atrial DEEP, the relationship between atrial DEEP and various clinical valuables including the pericardial fat volume and clinical outcomes was assessed.

A total of 102 patients were included and 45% had persistent AF. Fifty-three percent of patients exhibited DEEP properties. DEEP was more prevalent in patients with persistent AF (61% vs 39%, P < .001), higher brain natriuretic peptide levels (194 [interquartile range (IQR) 106–270] pg/mL vs 90 [IQR 23–174] pg/mL, P = .01), and a greater pericardiac fat volume (112 [IQR 63–76] cm3 vs 75 [IQR 53–95] cm3, P = .001). The patients with atrial DEEP had more early AF recurrence after ablation procedure (P < .001).

This study demonstrated a correlation between atrial DEEP and longer duration of AF, higher brain natriuretic peptide levels, greater pericardial fat volume, and more early AF recurrence, suggesting that DEEP reflects a certain aspect of atrial electrophysiological remodeling and is a potential ablation target for AF.