Abstract 12612: Employing Techniques to Maximize Lesion Contiguity and Transmurality During PV Isolation: Impact on the Durability of Electrical PV Isolation
Background: Durable PV isolation, the cornerstone of AF ablation, has been an elusive goal.
Objective: In an attempt to minimize gap-related PV reconnections, we instituted a series of modifications in RF ablation technique to maximize the possibility of lesion contiguity and transmurality. While a routine 2nd procedure would most accurately determine the durability of PVI, for practical reasons, we instead studied a cohort of pts with recurrent symptoms (though this cohort is likely to provide an underestimate of true PVI success). During the second procedures, we assessed the effect of this standardized series of modifications on the durability of PV isolation.
Methods: The PV isolation strategy consisted of: 1) circumferential PV isolation (CPVI) as ipsilateral PV pairs, 2) use irrigated RF catheter, 3) careful placement of contiguous lesions using deflectable sheath to maximize tissue contact, 4) attention to impedance drop during ablation, 5) full CPVI despite electrical isolation prior to full encirclement, 6) after PVI, additional ablation at areas of pace-capture on the ablation line, and 7) use of isoproterenol and adenosine to identify dormant conduction. Persistent AF patients received additional LA/RA ablation as needed.
Results: Of 81 consecutive patients (paroxysmal, n=42) who underwent RF ablation for AF, 14 (17%) underwent repeat mapping (for either recurrence or LAA closure). In the 14 pts (7 PAF / 7 PerAF), a 2nd procedure at 91±59 days revealed durable PV isolation in 26/28 PV pairs (93%) - translating to 12/14 (86%) pts with all PVs isolated. The two PV pair reconnections occurred in the RPVs: a breakthrough postero-inferior near the RIPV, and two breakthrough points in the RPVs in the second case. Of the 13 pts with clinical recurrences, 38% (n=5/13) were due to an atypical flutter; the remainder were due to non-PV related focal triggers.
Conclusions: Despite evaluating a patient cohort in whom the durability of PVI was likely to be underestimated (that is, pts with recurrent AF are most likely to have PV reconnections), these data indicate that durable PV isolation is yet achievable in >90% of PV pairs by using a standardized approach designed to maximize lesion contiguity and transmurality.
- © 2011 by American Heart Association, Inc.