Impact of Posterior Wall Isolation During AF Ablation on the Incidence of Left Atrial Flutter

Michael W Lim; Matthew Morton; Romaniya Fernando; Stefanie Elbracht-Leong; Nathan Better; Louise Segan; Jeremy William; Rose Crowley; Joseph B Morton; Paul B Sparks; Geoffrey Lee; Alex J McLellan; Liang-Han Ling; Hariharan Sugumar; Sandeep Prabhu; Aleksandr Voskoboinik; Jonathan M Kalman; Peter M Kistler

doi:10.1016/j.jacep.2024.04.008

Impact of Posterior Wall Isolation During AF Ablation on the Incidence of Left Atrial Flutter

JACC Clin Electrophysiol. 2024 May 9:S2405-500X(24)00286-X. doi: 10.1016/j.jacep.2024.04.008. Online ahead of print.

Authors

Michael W Lim¹, Matthew Morton², Romaniya Fernando³, Stefanie Elbracht-Leong³, Nathan Better⁴, Louise Segan⁵, Jeremy William⁵, Rose Crowley⁵, Joseph B Morton⁶, Paul B Sparks⁶, Geoffrey Lee⁷, Alex J McLellan⁸, Liang-Han Ling⁹, Hariharan Sugumar¹⁰, Sandeep Prabhu¹¹, Aleksandr Voskoboinik¹², Jonathan M Kalman¹³, Peter M Kistler¹⁴

Affiliations

¹ The Alfred Hospital, Melbourne, Australia; The Royal Melbourne Hospital, Melbourne, Australia; Melbourne Private Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia.
² Monash University, Melbourne, Australia.
³ Cabrini Health, Melbourne, Australia.
⁴ The Royal Melbourne Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia; Monash University, Melbourne, Australia.
⁵ The Alfred Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia.
⁶ The Royal Melbourne Hospital, Melbourne, Australia; Melbourne Private Hospital, Melbourne, Australia.
⁷ The Royal Melbourne Hospital, Melbourne, Australia; Melbourne Private Hospital, Melbourne, Australia; University of Melbourne, Melbourne, Australia.
⁸ The Royal Melbourne Hospital, Melbourne, Australia; University of Melbourne, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia; St Vincent's Health, Melbourne, Victoria, Australia.
⁹ The Alfred Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia.
¹⁰ The Alfred Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; Monash University, Melbourne, Australia; St Vincent's Health, Melbourne, Victoria, Australia.
¹¹ The Alfred Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia.
¹² The Alfred Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia; Western Health, Melbourne, Victoria, Australia.
¹³ The Royal Melbourne Hospital, Melbourne, Australia; Melbourne Private Hospital, Melbourne, Australia; University of Melbourne, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia; Monash University, Melbourne, Australia.
¹⁴ The Alfred Hospital, Melbourne, Australia; Melbourne Private Hospital, Melbourne, Australia; Cabrini Health, Melbourne, Australia; University of Melbourne, Melbourne, Australia; The Baker Heart and Diabetes Research Institute, Melbourne, Australia; Monash University, Melbourne, Australia. Electronic address: peter.kistler@baker.edu.au.

PMID: 38752960
DOI: 10.1016/j.jacep.2024.04.008

Abstract

Background: Linear and complex electrogram ablation (LCEA) beyond pulmonary vein isolation (PVI) is associated with an increase in left atrial macro-re-entrant tachycardias (LAMTs). Posterior wall isolation (PWI) is increasingly performed to improve AF ablation outcomes. However, the impact of PWI on the incidence of LAMT is unknown.

Objectives: The purpose of this study was to establish the incidence of LAMT following PVI alone vs PVI + PWI vs PVI + PWI + LCEA.

Methods: Consecutive patients undergoing catheter ablation for AF or LAMT post-AF ablation between 2008 and 2022 from 4 electrophysiology centers were reviewed with a minimum follow-up of 12 months.

Results: In total, 5,619 (4,419 index, 1,100 redo) AF ablation procedures were performed in 4,783 patients (mean age 60.9 ± 10.6 years, 70.7% men). Over a mean follow-up of 6.4 ± 3.8 years, 246 procedures for LAMT were performed in 214 patients at a mean of 2.6 ± 0.6 years post-AF ablation. Perimitral (52.8% of patients), roof-dependent (27.1%), PV gap-related (17.3%), and anterior circuits (8.9%) were most common, with 16.4% demonstrating multiple circuits. The incidence of LAMT was significantly higher following PVI + PWI (6.2%) vs PVI alone (3.0%; P < 0.0001) and following PVI + PWI + LCEA vs PVI + PWI (12.5%; P = 0.019). Conduction gaps in previous ablation lines were responsible for LAMT in 28.4% post-PVI alone, 35.3% post-PVI + PWI (P = 0.386), and 81.8% post-PVI + PWI + LCEA (P < 0.005).

Conclusions: The incidence of LAMT following PVI + PWI is higher than with PVI alone but significantly lower than with more extensive atrial substrate modification. Given a low frequency of LAMT following PWI, empiric mitral isthmus ablation is not justified and may be proarrhythmic.

Keywords: atrial fibrillation; atypical flutter; posterior wall isolation.