# Effects of Pulmonary Vein Isolation for Atrial Fibrillation on Skin Sympathetic Nerve Activity in Association with Left Atrial Remodeling

## TL;DR

This study shows that pulmonary vein isolation reduces skin sympathetic nerve activity in paroxysmal atrial fibrillation but not in persistent cases, possibly due to left atrial remodeling.

## Contribution

The study reveals that PVI's neuromodulatory effects are diminished in persistent AF due to left atrial remodeling.

## Key findings

- PVI significantly reduced SKNA burst amplitude and LF/HF ratio in paroxysmal AF patients.
- Persistent AF patients showed no significant changes in SKNA after PVI.
- A positive correlation was found between changes in LF/HF ratio and LA volume index in paroxysmal AF.

## Abstract

Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). While it is known to affect the autonomic nervous system, the relationship between left atrial (LA) remodeling and PVI-mediated neuromodulation remains unclear. We aimed to assess the neuromodulatory effects of PVI using skin sympathetic nerve activity (SKNA). SKNA was recorded one day before and 2–3 days after PVI in 28 paroxysmal AF (PAF) and 33 persistent AF (PerAF) groups. Baseline low frequency to high frequency (LF/HF) ratio was higher in the PAF group (1.23 [interquartile range {IQR}: 0.79–1.76] vs. 0.74 [IQR: 0.49–1.38], p = 0.017). After PVI, the PAF group demonstrated significant reductions in burst amplitude (1.46 [IQR: 1.04–2.84] vs. 1.09 [IQR: 0.78–2.17] μV, p = 0.015) and LF/HF ratio (0.91 [IQR: 0.73–1.52] vs. 0.71 [IQR: 0.48–1.21], p = 0.012), whereas the PerAF group exhibited no such changes. A weak positive correlation was observed between the percentage change in LF/HF ratio and LA volume index in the PAF group (r = 0.572, p = 0.002). PVI significantly decreased SKNA in PAF patients but not in PerAF. LA remodeling may hinder the effectiveness of PVI-mediated neuromodulation.