Recurrent Post-Ablation Paroxysmal Atrial Fibrillation Shares Substrates With Persistent Atrial Fibrillation

Abstract

Introduction The role of atrial fibrillation (AF) substrates is unclear in patients with paroxysmal AF (PAF) that recurs after pulmonary vein isolation (PVI). We hypothesized that patients with recurrent post-ablation (redo) PAF despite PVI have electrical substrates marked by rotors and focal sources, and structural substrates that resemble persistent AF more than patients with (de novo) PAF at first ablation. Methods In 175 patients at 11 centers, we compared AF substrates in both atria using 64 pole-basket catheters and phase mapping, and indices of anatomical remodeling between patients with de novo or redo PAF and first ablation for persistent AF. Results Sources were seen in all patients. More patients with de novo PAF (78.0%) had sources near PVs than patients with redo PAF (47.4%, p=0.005) or persistent AF (46.9%, p=0.001). The total number of sources per patient (p=0.444), and number of non-PV sources (p=0.701) were similar between groups, indicating that redo PAF patients had residual non-PV sources after elimination of PV sources by prior PVI. Structurally, left atrial size did not separate de novo from redo PAF (49.5±9.5 vs. 49.0±7.1mm, p=0.956) but was larger in patients with persistent AF (55.2±8.4mm, p=0.001). Conclusions Patients with paroxysmal AF despite prior PVI show electrical substrates that resemble persistent AF more closely than patients with paroxysmal AF at first ablation. Notably, these subgroups of paroxysmal AF are indistinguishable by structural indices. These data motivate studies of trigger versus substrate mechanisms for patients with recurrent paroxysmal AF after PVI.

High‐Normal Thyroid‐Stimulating Hormone Shows a Potential Causal Association With Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation

“…On the other hand, atrial tachyarrhythmia–free survivals in quartile 4 patients with paroxysmal AF were nearly identical with those with nonparoxysmal AF, as measured after both the first and the last session, indicating that the effectiveness of catheter ablation did not differ between quartile 4 patients with and without paroxysmal AF (Figure 3). This finding gives a new insight into understanding the mechanistic overlap theory between patients with paroxysmal and nonparoxysmal AF 15, 16…”

“…Thus, clinical success can be better achieved in patients with paroxysmal AF than in those with nonparoxysmal AF. However, recent reports have highlighted the heterogeneity within patients with paroxysmal AF, indicating that a subgroup of paroxysmal AF has the same arrhythmia substrate as nonparoxysmal AF and is resistant to PVI as a result 15, 16…”

The continuous challenge of AF ablation: From foci to rotational activity

“…(C) Traditional activation mapping, (D) phase mapping using published methods 38 and (E) Focal Impulse and Rotor Mapping (FIRM) each confirmed sustained rotations at the site where ablation terminated AF. Modified from references 66 and 48.…”

Ablation of Atrial Fibrillation Drivers

“…46 In most studies, AF drivers arise in diverse locations, overall with show similar AF driver distributions but in larger regions, 11 which may represent greater 'meander' in projecting from the heart to the Single procedure, acute and long-term outcomes of AF driver ablation when added to pulmonary vein isolation are presented. 11,12,14,27,45,[52][53][54][55][57][58][59][60][61][62][63][64] AER_Baykaner_FINAL.indd 198 05/12/2017 22:48…”

“…12,44,[52][53][54][55][56] In summary, the endpoint of AF driver ablation is the elimination of sustained rotational or focal activity that lie in conserved spatial locations. This endpoint is achievable in most patients, and may be superior to historical endpoints of AF termination.…”