# Left Pulmonary Vein Trunk Length as a Robust Predictor of Long-Term Success of Atrial Fibrillation Catheter Ablation

## TL;DR

This study finds that the length of the left pulmonary vein trunk is a strong predictor of whether atrial fibrillation will return after catheter ablation treatment.

## Contribution

The study introduces left pulmonary vein trunk length as a novel and robust predictor of long-term success in atrial fibrillation ablation.

## Key findings

- Longer left pulmonary vein trunk length is associated with higher recurrence risk after ablation.
- Left pulmonary vein trunk length improves multivariable model performance for predicting outcomes.
- A cut-off value of 11.15 mm for left pulmonary vein trunk length distinguishes recurrence risk.

## Abstract

Radiofrequency catheter ablation (RFCA) is a
commonly used treatment for atrial fibrillation (AF), but the long-term
recurrence rate remains relatively high. Given the inconsistent results regarding
the role of left pulmonary vein (PV) ostial anatomy in post-ablative recurrence
of RFCA in previous studies, we sought to investigate the role of left PV trunk
length using an alternative methodology.

A total of 369 AF
patients undergoing catheter ablation were included. The left/right trunk length
(LTL/RTL) of the PV was measured from pre-ablative computed tomography (CT) using three-dimensional
reconstruction techniques. We constructed three multivariable Cox models, with
the inclusion of the LTL, RTL, and no LTL/RTL, and used the Delong test,
integrated discrimination index (IDI), and net reclassification index (NRI) to
assess model improvement. We identified optimal cut-off values for LTL with the
receiver operating characteristic (ROC) curve, and estimated outcomes using the
Kaplan-Meier survival curve. We also used subgroup analysis to evaluate
interactions.

The results of the Delong test, IDI, and NRI
indicated that LTL had a favorable impact on the performance of the multivariate
model. Subsequently, the multivariate Cox regression analysis identified LTL as a
significant risk factor for post-ablative recurrence of AF (adjusted hazard ratio (HR) = 1.08,
95% CI: 1.05–1.12, p
< 0.001). According to the ROC curve, the
optimal cut-off value for LTL is 11.15 mm, and the Kaplan-Meier estimator revealed
different outcomes (p
< 0.001). We calculated p for
interaction between LTL and other factors, and no significant interaction terms
were observed.

LTL is a robust prognostic indicator for
post-ablative outcome in AF patients receiving RFCA, with a longer LTL indicating
a higher risk of recurrence.