Influence of High-Pass Filtering on Noncontact Mapping and Ablation of Atrial Tachycardias

• Published in: Pacing and clinical electrophysiology 2004-01, Vol.27 (1), p.38-46
• Main Authors: SCHNEIDER, MICHAEL A. E., NDREPEPA, GJIN, WEBER, STEFAN, DEISENHOFER, ISABEL, SCHÖMIG, ALBERT, SCHMITT, CLAUS
• Format: Article
• Language: English
• Subjects: atrial tachycardia; Body Surface Potential Mapping - methods; catheter ablation; Catheter Ablation - methods; Female; Follow-Up Studies; high-pass filter; Humans; Male; Middle Aged; noncontact mapping; Tachycardia, Ectopic Atrial - physiopathology; Tachycardia, Ectopic Atrial - surgery
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.2004.00383.x

The aim of the study was to define the impact of different high‐pass filter settings (HPF) on the accuracy of mapping of ectopic atrial tachycardias (EAT) using a noncontact mapping (NCM) system. In 20 patients with 22 EAT a noncontact probe was deployed in the right (n = 19) or in the left atrium (n = 3). The device enables interpolation and analysis of unipolar electrograms. It provides information on focus localization and signal morphology. These parameters were compared in different HPF of 0.5 Hz, 2 Hz, 8 Hz, and 16 Hz. The NCM signal morphology was preserved at all HPF. An initial negative deflection recorded by NCM system showed a positive predictive value of 93% regarding the ablation success. The deviation (spatial disparity) between visualized focus origin and successful ablation site was 6.9 ± 5.4 mm. Between two consecutive filter settings, the focus shift was more pronounced between 0.5 and 2 Hz (5.4 ± 4.5 mm) compared to a setting between 8 and 16 Hz (2.9 ± 2.9 mm; P < 0.05). Successful ablation was achieved in 15/18 right atrial tachycardias (83%) and in 2/3 left atrial arrhythmias. Different HPF influence NCM spatial analysis of EAT. However, a small variability in foci localization does not impact final ablation results. (PACE 2004; 27:38–46)