Simultaneously collected monopolar and discrete bipolar electrograms: comparison of activation time detection...

Area of Science:

• Cardiac Electrophysiology
• Medical Device Technology
• Biomedical Signal Processing

Background:

• Accurate determination of local activation time is crucial for electrophysiological mapping.
• The minimum slope in monopolar electrograms (MP) correlates with action potential phase 0 in normal myocardium.
• A comparable parameter for bipolar electrograms (BP), commonly used in studies, has not been established.

Purpose of the Study:

• To compare activation times derived from common bipolar electrogram algorithms with monopolar electrogram data.
• To evaluate the performance of different bipolar electrogram algorithms for activation time determination.

Main Methods:

• Simultaneous epicardial monopolar (MP) and bipolar (BP) electrograms were recorded from human subjects and dogs.
• Four algorithms were used to determine BP activation time: peak (P), greatest absolute slope (S), zero crossing (FZC), and morphological (M).
• BP-derived activation times were compared to the minimum slope time from simultaneously recorded MP electrograms.

Main Results:

• All tested BP algorithms produced activation time distributions statistically different from MP-derived times.
• The morphological (M) algorithm demonstrated superior performance with a small absolute difference (2.6 +/- 2.9 msec) and high correlation (0.9925 in humans).
• Outlier rates were lowest for the M algorithm (3.2%), followed by P (3.5%), FZC (4.7%), and S (4.7%).

Conclusions:

• A morphologically based algorithm for bipolar electrograms offers superior accuracy for determining local activation time compared to simpler slope or peak-based methods.
• This finding has significant implications for improving the precision of electrophysiological mapping during cardiac procedures.