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Updated: Sep 24, 2025

Non-fluoroscopic Catheter Tracking for Fluoroscopy Reduction in Interventional Electrophysiology
Published on: May 26, 2015
Dynamic changes in signal-averaged P wave after catheter ablation of atrial fibrillation
Dony Yugo1,2, Ming-Jen Kuo1,3, Yu-Feng Hu1,3
1Heart Rhythm Center, Taipei Veterans General Hospital, Taipei, Taiwan, ROC.
Background:
The comprehensive surveillance for interval changes in signal-averaged P-wave (SAPW) after pulmonary vein isolation (PVI) remains lacking. We aimed to analyze the SAPW parameters before and after PVI and explored their link to the left atrial electrical properties.
Methods:
Eighteen patients with paroxysmal atrial fibrillation receiving primary catheter ablation were enrolled. SAPW parameters, including root mean square voltages in the last 40, 30, and 20 ms (RMS40, RMS30, and RMS20, respectively), the total P-wave (RMSt), the integral of P-wave potentials (Int-p), and P-wave duration (fPWD), were measured before and after PVI and correlated to the left atrial activation time (LAT) and mean left atrial voltage (LAV) from electro-anatomical mapping.
Results:
Compared with the SAPW before PVI, fPWD (before vs after PVI: 144.1 ± 5.2 vs 135.1 ± 11.9 ms, p = 0.02), Int-p (687.4 ± 173.1 vs 559 ± 202.5 mVms, p = 0.01), and RMSt (6.44 ± 1.3 vs 5.44 ± 2.0 mV, p = 0.04) all decreased after PVI. RMS20, RMS30, and RMS40 showed no significant difference. Similarly, LAT (97.5 ± 9.3 vs 90.5 ± 9.3 ms, p = 0.008) and LAV (1.37 ± 0.27 vs 0.96 ± 0.31 mV, p = 0.001) decreased after PVI. Although consistent changes after PVI were observed between SAPW parameters and LAT or LAV, no linear correlation was observed among them.
Conclusion:
The consistent changes in SAPW and left atrial electrical properties after PVI suggest that SAPW may be used as a noninvasive tool to monitor the responses to PVI.
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