Characterization of unipolar electrogram morphology: a novel tool for quantifying conduction inhomogeneity

Area of Science:

• Cardiovascular Electrophysiology
• Cardiac Arrhythmia Research
• Medical Device Development

Background:

• Conduction inhomogeneity (CI) in the atria can trigger and sustain atrial fibrillation (AF).
• Existing methods lack tools to precisely measure the severity of CI.
• Quantifying CI is crucial for predicting AF risk and optimizing treatment.

Purpose of the Study:

• To develop and validate a novel tool for quantifying atrial CI severity.
• To utilize unipolar electrograms (EGMs) exclusively for CI assessment.
• To establish a reliable method for staging conduction abnormalities.

Main Methods:

• Epicardial mapping in 235 patients undergoing coronary artery bypass grafting surgery.
• Classification of electrograms into single, short, long double potentials (LDPs), and fractionated potentials (FPs).
• Development of the Electrical Fingerprint Score based on right atrial (RA) EGM features, including low-voltage areas (LVAs) and LDPs.

Main Results:

• Increased CI correlated with decreased EGM voltages and increased LVAs, LDPs, and FPs.
• The Electrical Fingerprint Score showed high accuracy in predicting CI severity.
• The RA Electrical Fingerprint Score demonstrated the strongest correlation with CI amount (r = 0.70, P < 0.001).

Conclusions:

• The Electrical Fingerprint Score is a novel tool for quantifying CI severity using unipolar EGMs.
• This score enables staging of conduction abnormalities without complex spatial mapping.
• It holds potential for early identification of AF risk and personalized ablation strategies.