P‐wave morphology and multipolar intracardiac atrial activation to facilitate nonpulmonary vein trigger localization

Abstract

Introduction: Nonpulmonary vein (non-PV) triggers of atrial fibrillation (AF) are targets for ablation but their localization remains challenging. The aim of this study was to describe P-wave (PW) morphologic characteristics and intra-atrial activation patterns and timing from multipolar coronary sinus (CS) and crista terminalis (CT) catheters that localize non-PV triggers.Methods and Results: Selective pacing from six right and nine left atrial common non-PV trigger sites was performed in 30 consecutive patients. We analyzed 12 lead ECG features based on PW duration, amplitude and morphology, and patterns and timing of multipolar activation for all 15 sites. Regionalization and then precise localization required criteria present in at least 70% of assessments at each pacing site. The algorithm was then prospectively evaluated by four blinded observers in a validation cohort of 18 consecutive patients undergoing the same pacing protocol and 60 consecutive patients who underwent successful non-PV trigger ablation.The algorithm for site regionalization included 1) negative PW in V1, ≥30 µV change in PW amplitude across the leads V1-V3, and PW duration ≤100 milliseconds in lead 2 and 2) unique intra-atrial activation patterns and timing noted in the multipolar catheters. Specific ECG and intra-atrial activation timing characteristics included in the algorithm allowed for more precise site localization after regionalization. In the prospective evaluation, the algorithm identified the site of origin for 72% of paced and 70% of spontaneous non-PV trigger sites.Conclusion: An algorithm based on PW morphology and intra-atrial multipolar activation pattern and timing can help identify non-PV trigger sites of origin. K E Y W O R D S atrial fibrillation, catheter ablation, nonpulmonary vein trigger, P wave J Cardiovasc Electrophysiol. 2019;30:865-876. wileyonlinelibrary.com/journal/jce © 2019 Wiley Periodicals, Inc. | 865 Abbreviations for non-PV trigger sites: ER, Eustachian ridge; HPW, high posterior wall; IPW, inferior posterior wall; LAAFW, left atrial appendage free-wall side; LAAR, left atrial appendage ridge side; LHS, left high septum; LLS, left low septum; LMVA, lateral mitral valve annulus; LPHIS, left para-Hisian site; MCT, crista teminalis mid to low; MPW, mid-posterior wall; RAA, right atrial appendage; RPHIS, right para-Hisian site; SFR, right septum-fossa region.

Approach to recurrent atrial fibrillation with isolated pulmonary veins

“…If there is still no AF, then burst pacing into AF followed by cardioversion under residual or low dose Prel can be effective. If AF occurs, the trigger can be localized by maneuvering catheters to the region of interest based on earliest recording during AF initiation and utilizing the activation pattern on the right atrial and CS catheters 1 ; multiple repeat cardioversions are often needed. Knowledge of common trigger sites for AF helps in this process 2 …”

Persistent atrial fibrillation: When the pulmonary veins are no longer the answer

“…For this reason and to improve catheter stability with low‐volume, high‐frequency ventilation, we routinely use general anesthesia 1 . In most situations, more than one cardioversion is required to precisely localize the trigger site after quick regionalization by assessing the p‐wave morphology and multipolar catheter activation 4 . Typically, the same trigger is seen repeatedly and we localize the trigger origin with a multipolar mapping catheter placed in the anticipated region of interest.…”

“…1 In most situations, more than one cardioversion is required to precisely localize the trigger site after quick regionalization by assessing the p-wave morphology and multipolar catheter activation. 4 Typically, the same trigger is seen repeatedly and we localize the trigger origin with a multipolar mapping catheter placed in the anticipated region of interest. Repeated cardioversion and spontaneous atrial fibrillation reinitiation may be required for precise localization.…”

“…In most cases, if a single AF episode occurs, regionalization of the trigger can be determined using an algorithm that assesses the activation sequence in the multipolar catheters and if possible the p-wave morphology. 4 In patients in whom triggers cannot be initiated, a more empiric, approach is typically considered, but still with a focus on trigger elimination. A common source of non-PV triggers is the posterior wall, which may be in part due to the embryologic homology shared between the posterior wall and the PVs.…”

“…Challenges encountered when targeting non‐PV triggers sites, including the presence of multiple anatomically distinct triggering sites, the uncommon lack of reproducibility of AF reinitiation and the lack of any triggers despite all provocative maneuvers and the clinical history of spontaneous AF. In most cases, if a single AF episode occurs, regionalization of the trigger can be determined using an algorithm that assesses the activation sequence in the multipolar catheters and if possible the p‐wave morphology 4 …”