# A Case of Roof‐Dependent Atrial Flutter With an Endocardial Narrow Channel Successfully Visualized by the Peak Frequency Analysis

## TL;DR

This paper presents a case where peak frequency analysis helped identify a narrow heart channel during a difficult atrial flutter treatment.

## Contribution

The paper introduces the use of peak frequency analysis to visualize narrow endocardial channels in atrial flutter.

## Key findings

- Peak frequency analysis successfully visualized a narrow endocardial channel in a case of roof-dependent atrial flutter.
- The technique helped physicians select an optimal therapeutic target for a transmural line of block.

## Abstract

Roof‐dependent atrial flutter (AFL) can sometimes be challenging to treat with endocardial catheter ablation due to the thickness of the atrial myocardium and the separation of outer epicardial conductive fibers from the endocardial myocardium. This case highlights the utility of peak frequency (PF) analysis during the AFL, which can visualize a narrow endocardial channel and help physicians select an optimal therapeutic target to achieve a transmural line of block.