Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Mapping & Imaging D-PO04 - Poster Session IV (ID 15) Poster

D-PO04-193 - Validation Of A Novel High-resolution Local CV Mapping Technique: Calculated Unipolar Local Activation Time Differences From Peak Bipolar Voltage Amplitude (ID 491)

  S.A. Gaeta: Honoraria/Speaking/Consulting Fee - Biosense Webster, Inc..


Background: Local conduction velocity (CV) mapping can identify pro-arrhythmic tissue and facilitate substrate characterization. Accuracy and resolution of CV calculation improves with improved local activation time (LAT) measurement.
Objective: Validate a novel high-resolution technique—\"Determination of Electrogram Latencies by Transformation of Amplitude\" (DELTA)—in which the unipolar LAT difference (Δt) between electrodes is calculated from the peak amplitude (Vp) of their resulting bipolar electrogram (EGM).
Methods: 18,740 atrial EGMs were recorded from 10 atrial fibrillation patients during pacing. Local CV mapping was performed in a healthy adult swine using an 8x8 electrode array (2mm spacing). 498 unique local CV vectors (mean 99.6 per beat) were calculated using Δt measured by DELTA and by standard technique.
Results: Theoretical modeling predicted a quantitative relationship between Δt and Vp. Computational modeling demonstrated accuracy of DELTA-derived Δt to as close as 5 microseconds, even with 1KHz sampling. The predicted correlation between measured Vp and Δt was seen in clinically recorded EGMs (Fig 1A). Local CV mapping using DELTA measurements accurately reproduced local activation patterns and speeds compared to standard LAT measurement technique (Fig 1B-C).
Conclusion: High-resolution LAT differences can be accurately calculated from peak bipolar EGM amplitude using the DELTA method. This may enable local CV mapping at smaller scales and with higher accuracy.