# Dual Chamber Open Window Mapping and High‐Density Mapping for Atrioventricular Reentrant Tachycardia Associated With Atrioventricular Mahaim Fiber

## TL;DR

This paper describes a technique combining dual-chamber open-window and high-density mapping to identify and treat a rare heart condition caused by an abnormal electrical pathway.

## Contribution

The study introduces a novel mapping approach for locating and ablating Mahaim fibers in atrioventricular reentrant tachycardia.

## Key findings

- Early atrioventricular conduction was identified on the lateral tricuspid annulus using the mapping techniques.
- Catheter ablation at the ventricular insertion site successfully eliminated the accessory pathway.
- Tachycardia was no longer inducible after the ablation procedure.

## Abstract

Dual‐chamber open‐window mapping (OWM) combined with high‐density mapping revealed early atrioventricular conduction on the lateral tricuspid annulus, consistent with a Mahaim fiber. Catheter ablation targeting the ventricular insertion site led to successful elimination of the accessory pathway and noninducibility of tachycardia.