Signal-averaged intracardiac electrograms: a new method to detect kent potentials

Area of Science:

• Electrophysiology
• Cardiac Arrhythmia Management
• Signal Processing in Medicine

Background:

• Identifying accessory pathways via Kent potentials is challenging due to signal noise and catheter instability.
• Accurate localization is crucial for successful catheter ablation in patients with manifest accessory pathways.

Purpose of the Study:

• To evaluate if signal averaging of intracardiac electrograms improves Kent potential detection.
• To assess the utility of signal averaging in identifying accessory pathway locations for ablation.

Main Methods:

• Retrospective analysis of electrograms from 25 patients undergoing accessory pathway ablation.
• Development of custom software for signal averaging (SAE) of 20-30 consecutive sinus beats.
• Quantification of catheter instability using the variability quotient (VQ).

Main Results:

• Signal averaging identified probable Kent potentials in 10/15 successful/transiently successful sites, compared to only 2/15 in raw electrograms (P=0.008).
• High VQ (>0.2) indicating unstable catheter contact was observed in 3/6 transiently successful sites.
• Stable catheter contact (VQ <0.2) was associated with 8/9 successful ablation sites.

Conclusions:

• Signal averaging of intracardiac electrograms significantly enhances the detection of Kent potentials.
• Variability quotient analysis quantifies catheter instability, potentially predicting ablation success.
• Improved detection of Kent potentials and assessment of catheter stability can optimize accessory pathway ablation outcomes.