Impact of adjunctive posterior wall isolation with pulsed field ablation on inducibility of atrial flutter following pulmonary vein isolation

The safety and efficacy of pulsed field ablation (PFA) for pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF) is well-established. Increasingly, posterior wall isolation (PWI) with PFA has been used as an adjunctive ablation strategy. The impact of PWI with PFA on post-ablation inducibility of reentrant atrial tachycardias/flutters (ATs) is unclear.

To characterize and compare inducible reentrant ATs among patients undergoing PVI with and without adjunctive PWI for de novo catheter ablation of AF.

Patients undergoing PFA using a pentaspline catheter (Farapulse, Boston Scientific) for first-time catheter ablation of AF were included in the study. Demographic, clinical and imaging data as well as procedural characteristics were collected. All patients underwent post-ablation programmed atrial stimulation with and without isoproterenol/dobutamine.

A total of 228 patients (mean age 67±11 years; 76 (33%) female) were included in the study. One hundred and three (45%) patients underwent adjunctive PWI at operator discretion. Overall, 38 (17%) patients had inducible reentrant ATs post-initial ablation, which included 24 (11%) with cavotricuspid isthmus-dependent, 1 (0.44%) with peri-tricuspid, 8 (3.5%) with peri-mitral, 1 (0.44%) with anterior LA, 2 (0.88%) with roof-dependent LA, 2 (0.88%) with septal, and 2 (0.88%) with SVC-dependent ATs. There was no significant difference in rate of inducibility of reentrant ATs between those who did and did not undergo PWI (20% vs. 14%; p=0.2117). After excluding inducible right ATs, 9 (9%) patients in the PWI group (example shown in Figure) compared to 4 (3%) patients in the non-PWI group had inducible left ATs (p=0.0888).

Adjunctive PWI with PFA was associated with low rates of inducible left reentrant AT after initial ablation. The impact of adjunctive PWI with PFA on long-term freedom from AT/AF remains to be defined.

septal AT after PWI (1/2)