Abstract 2474: ATP-induced Dormant Pulmonary Vein Origins After Circumferential Pulmonary Vein Isolation of Atrial Fibrillation
Purpose An ATP injection after pulmonary vein electrical isolation (PVEI) has been reported to be an effective method to merge transient reconnections between the left atrium and isolated PVs (dormant PV). Additional RF applications to eliminate dormant PV have been reported to reduce atrial fibrillation (AF) recurrences after PVEI. However, the site to ablate for elimination of dormant PV has not been evaluated.
Materials and Methods A total of 274 consecutive symptomatic AF patients (58±10 years) underwent circumferential PVEI (CPVEI) with a double lasso technique. They were divided into two groups in a retrospective review; Group1: those given a 10mg injection of intravenous ATP during an intravenous isoproterenol infusion after the CPVEI (n=165), and Group2: those in which it was not given after the CPVEI (n=109). At first RF energy was applied at the earliest dormant PV activation site recorded and identified on the lasso catheter on the circumferential ablation line. Additional RF applications were delivered in the carina region between the superior and inferior PVs if adenosine-induced reconnections were still recognized.
Results In both the left and right ipsilateral PVs in Group1, immediate PVEI sites were located on the carina region within the CPVI line (52% and 38.5%), roof of the superior PV (22.5% and 21%) and bottom of the inferior PV (7% and 27%). After a successful CPVEI, 77 patients (47%) in Group1 had PV reconnections during the 10mg intravenous ATP injection during the isoproterenol infusion. Dormant PVs were re-isolated on the carina region (55.5%), posterosuperior (10.5%) and posteroinferior (10.5%) of the left PVs and on the carina region (42%), floor (22%) and roof (17.5%) of the right PVs. The distribution of dormant PV sites, except for right superior PVs, significantly differed from that of immediate PVEI sites (p<0.05). Further, sinus rhythm was significantly preserved in Group1 as compared to Group2 patients during 9.1±4.9 months of follow-up (92.9% vs. 82.5%, p<0.05).
Conclusions The site to ablate for elimination of dormant PV in many cases was carina region, which was different from first immediate PVEI sites. These findings suggest that the carina region origins may partly be responsible for dormant PV and potential recurrences.