Electrophysiological and anatomical characteristics of pulmonary vein isolation with "crosstalk" effect during cryoballoon ablation

Objective We aimed to explore the electrophysiological and left atrial anatomical characteristics of pulmonary vein isolation (PVI) with the crosstalk technique during second-generation cryoballon ablation and figure out a better practice of this technique. Methods A total of 504 patients with atrial fibrillationwere included. All of these patients underwent initial ablation with second-generation cryoballoon. Among these patients, 89 patients (17.7%) did not achieve left/right superior pulmonary vein (LSPV/RSPV) isolation during first cryoablation. In the study group, there were 35 (39.3%) patients had crosstalk phenomenon. The remaining 54 patients (60.7%) without crosstalk were included in the control group. The baseline data, electrophysiological and anatomic characteristics of left atrium were compared between study group and control group. Results In the crosstalk group, 33 patients (94.3%) had crosstalk phenomenon in the LSPV. All of the patients (100%) had pulmonary vein potentials (PVP) delay during first cryoablation in the crosstalk group. Otherwise, PVP delays were observed in only 39 patients (72.2%) in the control group (P<0.05) . The total ablation time [ (281.1±103.1) s vs. (335.2±85.56) s, P<0.05]and frequency [ (1.85±0.86) times vs. (2.12±0.65) times, P< 0.05]were different between these two groups. As for the anatomic characteristics, the average distance from LSPV to inferior pulmonary vein was shorter in the crosstalk group [ (6.12±1.19) mm vs. (7.6±1.39) mm, P<0.05]. Similarly, the average distance of RSPV and inferior pulmonary veins was also shorter in study group [ (6.25±0.21) mm vs. (8.44±1.58) mm, P< 0.05]. Conclusion The crosstalk phenomenon was more frequent in the left pulmonary vein. Short distance between superior and inferior pulmonary vein and PVP delay during ablation could predict the crosstalk phenomenon. Key words: Atrial fibrillation; Cryoballoon; Pulmonary vein isolation; Crosstalk; Anatomical characteristics