Clinical Electrophysiology -> Ventricular Arrhythmias -> Experimental methods D-PO05 - Poster Session V (ID 39) Poster

D-PO05-241 - Optimization Of Near-field Electrogram Components For Mapping Of Scar-related Ventricular Tachycardia Substrate: Electrogam “Tuning” With Omnipolar Mapping Technology (ID 606)

 T. Nishimura: Nothing relevant to disclose.


Background: Bipolar electrograms frequently represent a summation or combination of both far-field and near-field components. We hypothesized that near-field electrogram may be magnified by dynamically adjusting (tuning) the bipole orientation relative to the activation wavefront recorded with a fixed grid catheter.
Objective: To investigate the impact of ventricular electrogram tuning on abnormal electrogram characteristics.
Methods: Retrospective analysis of 10 of the latest abnormal electrograms was performed with developmental omnipolar software in 10 patients. Electrograms were manually tuned by adjusting the orientation of the bipoles. The minimum and maximum bipolar amplitude of both far-field (systolic) and near-field (late potential) were recorded to assess the range of voltages that could be detected at a single site.
Results: 100 late potentials activate 161 [141-203] ms after QRS onset were analyzed. The far-field amplitude of 0.24 [0.13-0.62] mV ranged from 0.13 [0.09-0.27] mV- 0.29 [0.16-0.79] mV with tuning 360 degrees around the wavefront. The near-field amplitude ranged from 0.07 [0.03-0.13] mV- 0.26 [0.13-0.44] mV with tuning. In 19% of cases, the near-field and far-field component amplitudes could be reversed by magnification of near-field components. In 7% of cases, tuning revealed EGM components not originally detected with standard orientations.
Conclusion: Dynamic “tuning” of the same recorded electrogram from a fixed grid catheter with omnipolar technology may allow improved detection, characterization, and differentiation of near-field electrogram components relative to far-field signals.