Results:
Pre-PFA TJVS induced sinus pauses of 10.1 ± 2.74 seconds. A sinus block of over 3 seconds was present in 23 out of 24 patients. Post-PFA, the Right Superior Pulmonary Vein (RSPV) showed the highest decrease of TJVS-induced sinus pauses (RSPV: before 8.41 ± 4.53 vs after 3.27 ± 3.53 sec, p<0.001, RIPV: before 6.76 ± 4.54 sec vs. 6.89 ± 5.07 sec, p=0.90; LSPV: before 6.76 ± 5.25 sec vs. after 6.93 ± 4.29 sec, p=0.61; LIPV: before 7.80 ± 4.06 sec vs. after 7.88 ± 3.84 sec, p=0.91). Notably, sinus blocks over 3 seconds decreased significantly after RSPV ablation (19 before PFA, 10 after PFA, p<0.01), with less dramatic changes in other veins (RIPV: before 19, after 16, p=0.33; LSPV: before 14, after 19, p=0.11; LIPV: before 21, after 21, p=1.00). RSPV PFA also had the strongest impact on TJVS-induced AV block duration compared to the remaining veins (RSPV: before 6.49 ± 3.48 vs after 4.07 ± 3.27 sec, p<0.01, RIPV: before 6.00 ± 3.29 sec vs. 4.58 ± 3.99 sec, p=0.08; LSPV: before 5.15 ± 3.94 sec vs. after 5.14 ± 3.48 sec, p=0.93; LIPV: before 6.06 ± 3.98 sec vs. after 5.83 ± 3.44 sec, p=0.38). The incidence of AV blocks over 3 seconds was markedly reduced post-RSPV and post RIPV ablation (RSPV: before:19 vs. after: 14, p=0.11, RIPV: before:19 vs. after: 14, p=0.11), with minor changes in other veins (LSPV: before 14, after 16, p=0.55; LIPV: before 17, after 18, p=0.77).
Conclusions: PFA applications during pulmonary vein isolation have acute effect on the autonomic nervous system, as evidenced by the decrease in TJVS-induced sinus and atrioventricular block at the level of the right superior pulmonary vein. PFA-induced pauses are more frequent during applications on the LSPV, and less frequent when prior isolation of the RSPV has been performed, suggesting a vagally-mediated mechanism involving the right superior and/or right posterior ganglionated plexi.