Co-Author(s):
Jana Haskova, MD - electrophysiologist, Institute for Clinical and Experimental Medicine (IKEM)
Predrag Stojadinovic, MD - electrophysiologist, Institute for Clinical and Experimental Medicine (IKEM)
Petr Peichl, MD, PhD - Director of EP labs, Institute for Clinical and Experimental Medicine (IKEM)
Institute for Clinical and Experimental Medicine (IKEM)
Videnska 1958/9, 14021 Prague, Czech Republic
Introduction | Objectives: Current electrophysiology (EP) recording systems may exhibit noise, artifacts and interference that obscure clinically important low voltage electrograms (EGMs). Furthermore, their reliance on 50Hz/60Hz notch filtering may distort EGMs, impacting interpretation. We compared recordings from conventional EP recording systems to those from a novel system designed to reduce noise and minimize filtering.  
Methods: EGMs were recorded simultaneously from nine patients undergoing ablation using conventional diagnostic, mapping and ablation catheters, with the CathVision CubeTM EP System (CathVision, Copenhagen, Denmark) in parallel with the GE CardioLab (Control) and one of two 3D mapping systems (Carto3 or Ensite). EGMs were recorded using Wilson Central Terminal, filtering between 0.05 – 500 Hz, with and without notch filters. One minute periods of unfiltered unipolar signals from baseline and during RF ablation were analyzed in 10-second windows for the spectral power density of powerline noise and signal saturation. Control notch-filtered unipolar and bipolar EGM morphology and peak amplitude were compared to that of Cube unfiltered unipolar EGMs. Furthermore, the operator evaluated the compatibility of the Cube with the 3D mapping systems and catheters.
Results: At 50 Hz the mean Cube power was 6.1 times lower than Control. Saturation artifact was observed during every Control but no Cube ablations. Notch-filter induced EGM morphology changes (reduced amplitude, phase distortion, and artificial peaks) were observed in five Control but no Cube recordings (Fig). The Cube was compatible with both conventional 3D mapping systems and commercially available catheters.
Conclusions: CathVision Cube system EGM recordings were associated with fewer noise and signal artifacts, than the conventional systems. The notch filtering required to reduce conventional system noise distorted EGMs causing EGM fractionation that was not present on unfiltered Cube unipolar EGMs. The CathVision Cube is a novel EP recording system that provides EGM data not apparent on conventional systems, which may be clinically important.