Usefulness of filtered unipolar electrogram morphology for evaluating transmurality of ablated lesions during pulmonary vein isolation

AbstractBackgroundAlthough alteration of the amplitude and morphology of bipolar electrograms is used widely as a guide of the ablation effect, there is little information concerning unipolar electrograms. The amplitude and morphology of filtered bipolar (BP) and filtered unipolar (UP) electrograms were compared during pulmonary vein isolation in patients with atrial fibrillation.MethodsBP (30–250Hz) and UP (30–100Hz) signals from the ablation catheter were recorded before and after each ablation point at the pulmonary vein antrum in 6 patients with atrial fibrillation.ResultsIn the electrogram group with low-voltage amplitude in BP electrograms before ablation (