Related Experiment Video
Updated: May 17, 2026

Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
Published on: April 11, 2025
P-wave morphology of Bachmann bundle pacing based on electroanatomic mapping and intracardiac echocardiography
Soichiro Yamashita1, Mitsuru Takami2, Kimitake Imamura2
1Department of Cardiology, Hyogo Prefectural Awaji Medical Center, Sumoto, Japan.
Background:
Optimal criteria for Bachmann bundle (BB) pacing have not been established with direct anatomic visualization of BB engagement.
Objective:
This study aimed to further characterize the optimal site for BB pacing incorporating local electrogram (EGM) and P-wave morphology.
Methods:
This study included 20 patients who underwent a catheter ablation for atrial fibrillation. First, the right atrial BB insertion (BBRA) was identified anatomically by electroanatomic mapping (EAM) and intracardiac echocardiography. Local EGMs at and surrounding the anatomically defined BB were analyzed using a multipolar planar mapping catheter. Second, pace mapping was performed at 5 areas around and within the BB, and their P-wave morphologies were analyzed.
Results:
In all cases, the echocardiographically identified BB was consistent with the BB determined by EAM. Local EGMs at the BBRA vary morphologically. In the P-wave morphology of the BBRA pacing, (1) the 12-lead P-wave axes recapitulated normal sinus rhythm (SR) P waves, (2) inferior P-wave amplitude increased with BB capture relative to the native SR P wave, (3) the P-wave duration was >10 ms shorter than that of the SR, and (4) there was no isoelectric interval pacing centrally at the right atrial BB breakout area. If all these 4 criteria are met, the BB can be predicted with 95% sensitivity and 86% specificity.
Conclusion:
Using a combined definition of the BB using EAM and intracardiac echocardiography, paced P-wave parameters were identified that can be used to confirm BB capture with high sensitivity and specificity, which could be useful when targeting the BB for permanent atrial pacing.
More Related Videos
Related Concept Videos
Electrocardiogram Fundamentals
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
An electrocardiogram (ECG) visualizes the heart's electrical activity by tracing the electrical movement associated with each heartbeat on a graph or monitor. As the heart beats, an electrical wave passes through it, correlating with the cardiac cycle events.
Parts of an ECG
An ECG utilizes electrodes on the skin to...
Electrocardiogram
Three major waveforms are present in a typical ECG recording: the P wave, the QRS complex, and the T...
Dysrhythmias IV: Characteristics of Bradyarrhythmias
Correlation between ECG and Cardiac Cycle
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
Electrophysiology of Normal Cardiac Rhythm
ECG Interpretation of Arrhythmias II: Atrial, Junctional and Ventricular Arrhythmias

