# Phenotypic Analysis of P‐Wave Morphology as a Key Determinant of Late Recurrence Post‐Ablation in Paroxysmal Atrial Fibrillation

## TL;DR

This study finds that specific patterns in P-wave morphology, especially when combined, can predict the risk of arrhythmia recurrence after atrial fibrillation ablation.

## Contribution

The study introduces a novel phenotypic classification based on P-wave morphology to predict late recurrence after catheter ablation for atrial fibrillation.

## Key findings

- Phenotype 3, combining prolonged P-wave duration and low P-wave amplitude, showed the highest risk of late arrhythmia recurrence.
- Phenotype 3 had significantly higher recurrence rates at 1 and 3 years compared to other phenotypes.
- Phenotype 3 correlated with higher scores in low voltage area prediction models and clinical markers of advanced atrial remodeling.

## Abstract

It remains unclear how P‐wave morphology characteristics can be used to stratify the risk of late recurrence after catheter ablation (CA) for atrial fibrillation (AF).

Patients with paroxysmal AF who underwent an initial CA were enrolled. We investigated the association between P‐wave morphology (P‐wave duration (Pd), PQ interval, P‐wave amplitude (PWA) in leads II, V2, and V6) and late arrhythmia recurrence. Patients were classified into groups using statistical methods, and differences in recurrence and predictive scores for low voltage areas (LVA) among the groups were evaluated.

A total of 1005 paroxysmal AF patients undergoing initial CA were included. Cox regression identified female sex, Pd > 124 ms, PQ > 196 ms, and low PWA in leads II, V2, and V6 as predictors of late recurrence. Hierarchical clustering defined three phenotypes: Phenotype 1 (isolated low PWA), Phenotype 2 (isolated prolonged Pd) and Phenotype 3 (low PWA with prolonged Pd). At 1‐year, cumulative recurrence rates were 10.1% (95% CI 0.8–15.7), 7.0% (4.7–9.6), and 36.2% (30.8–42.3) for Phenotypes 1–3; at 3‐year, rates were 17.4% (12.8–23.3), 10.2% (7.4–14.0), and 61.2% (54.8–67.6). Phenotype 3 showed the highest risk, with HRs of 4.84 (95% CI 3.42–6.84) versus Phenotype 1 and 7.44 (4.34–12.8) versus Phenotype 2 (both p < 0.001). Phenotype 3 also had higher DR‐FLASH and APPLE scores than the other phenotypes.

Low PWA across multiple leads (II, V2, and V6), especially when combined with prolonged Pd, correlates with late arrhythmia recurrence and suggests the potential presence of LVA.

Phenotype 3, defined by the combination of prolonged Pd and low PWA in leads II, V2, and V6—representing orthogonal planes—was associated with the highest risk of late arrhythmia recurrence after CA, compared to Phenotype 1 (isolated low PWA) and Phenotype 2 (isolated prolonged Pd). This phenotype also demonstrated the highest scores in LVA prediction models (DR‐FLASH and APPLE), suggesting advanced atrial remodeling. Clinically, patients with Phenotype 3 were characterized by relatively older age, higher body mass index, hypertension, renal dysfunction, elevated BNP levels, and enlarged left atrial and ventricular diameters. BNP, brain natriuretic peptide; CA, catheter ablation; LVA, low voltage area; Pd, P‐wave duration; PWA, P‐wave amplitude.