Impact of Pulmonary Vein Isolation on Fractionated Atrial Potentials and Ganglionated Plexi in Patients With Persistent Atrial Fibrillation

Some patients with persistent atrial fibrillation (AF) acquire long-term freedom from AF by pulmonary vein (PV) isolation alone. The aim of the present study was to evaluate the characteristics of their atrial substrate. We studied 20 patients with persistent AF to examine the distribution of fractionated atrial potentials (FAP) and that of the anatomic sites of ganglionated plexi (GPs) with vagal reflexes elicited by high frequency stimulation (HFS) with the use of the CARTO system before and after the PV isolation. Both the %FAP area defined as a proportion of the FAP area to the total left atrial area (34.3 +/- 10.3 to 21.5 +/- 10.2%; P < 0.0001) and number of GP sites with vagal reflexes (4.0 [3.0, 5.0] to 2.0 [1.0, 2.8]; P < 0.0001) were markedly decreased after the PV isolation. Seven (35%) patients had AF recurrences, and they had a greater %FAP area after the PV isolation than those without (32.8 [22.1, 37.3] versus 13.8 [10.9, 19.91%; P = 0.0049). A %FAP area after the PV isolation of > 20% was significantly associated with an AF recurrence (odds ratio 20.0, 95% confidence interval 2.26-470.34; P = 0.018). No significant difference was found between the patients with and without AF recurrence in the reduction rate of anatomic sites of GPs with a vagal reflex induced by the HFS. A more marked reduction in the FAP area by the PV isolation was significantly associated with a better outcome in patients with persistent AF.