Additional LVZ-based substrate modification after PVI improved the outcome in PeAF patients with LVZs, whereas PVI alone worked in patients without LVZs, even in those with PeAF.

There was a significant slowing of local conduction in the LVZ defined as <0.5 mV and was frequently associated with fractionated or double potentials in patients with AF.

Background Atrial fibrillation (AF) is associated with heart failure (HF) rehospitalization in patients with heart failure with preserved ejection fraction (HFpEF). Objective We tested the hypothesis that catheter ablation of AF could reduce HF rehospitalization compared with conventional pharmacotherapy in patients with HFpEF. Methods Eighty‐five consecutive HFpEF (EF ≥ 50% and a history of HF hospitalization) patients diagnosed as AF by 12‐lead electrocardiogram were retrospectively analyzed. Thirty‐five patients who received catheter ablation (ABL group) were compared with 50 patients treated by antiarrhythmic drugs and/or beta‐blockers (CNT group). The primary endpoint was rehospitalization due to HF. Results The patients characteristics did not differ between the two groups including, age (71 ± 8 vs 71 ± 13 years; P = .637), female sex (34% vs 36%; P = .870), mean plasma brain natriuretic peptide (145 ± 112 vs 195 ± 153 pg/mL; P = .111), mean left ventricular ejection fraction (62% ± 8% vs 61% ± 9%; P = .624), and type of AF (nonparoxysmal AF 60% vs 62%; P = .852). Amiodarone was continued 40% (14 out of 35) and 40% (20 out of 70) in ABL and CNT groups, respectively (P = 1.000). Neither major complication nor major side effect was observed during the follow‐up period. During a mean follow‐up period of 792 ± 485 days, Kaplan‐Meier curve analysis showed that significantly more patients in the ABL group were free from HF rehospitalization (log‐rank P = .0039). Additionally, multivariate analysis revealed that catheter ablation of AF was the only preventive factor of HF rehospitalization (OR = 0.15; 95% CI: 0.04‐0.46; P < .001). Conclusions Catheter ablation of AF reduced HF rehospitalization compared with conventional pharmacotherapy in patients with HFpEF in our institute. Multicenter randomized study is warranted to confirm the result.

The LVZ area was an independent predictor of recurrence after PVAI without any LA substrate modification. Adenosine triphosphate-induced PV reconnection was also an independent predictor, especially in those without LVZs.

The extent of LVZ is an independent predictor for recurrence even after LVZ homogenization.

External anatomical structures contacting the LA may be related to unique conduction properties in diseased myocardium necessary for PsAF maintenance.

Non-PV foci are prevalent in the LA roof and SVC sites, but can originate from other sites as well. When non-PV foci are observed, PVI may be insufficient and should be supplemented with non-PV foci ablation.

Background: Macroreentrant atrial tachycardia (AT) accounts for 40% to 60% of recurrent atrial arrhythmias after atrial fibrillation (AF) ablation. To describe late gadolinium enhancement magnetic resonance imaging (LGE-MRI)–detected scar-based dechanneling as new ablation strategy to treat ATs after AF ablation. Methods: Data from 102 patients who underwent initial AF ablation and repeat ablation for recurrent atrial arrhythmia within 1-year follow-up were analyzed. All patients underwent LGE-MRI before initial and repeat ablation. Depending on the recurrent rhythm, patients with AF and AT recurrence were assigned to group 1 or 2, respectively. Group 1 underwent fibrosis homogenization as second procedure. Group 2 underwent LGE-MRI–detected scar-based dechanneling. Both groups underwent reisolation of pulmonary veins if necessary. Results: Forty-six patients (45%) presented with AF, and 56 patients (55%) presented with AT recurrence during follow-up after initial ablation. In the first 25 patients from group 2, the AT was electroanatomically mapped, and a critical isthmus was defined. It was found that those isthmi were located in the regions with nontransmural scarring detected by LGE-MRI. In the last 31 patients from group 2, an empirical LGE-MRI–based dechanneling was performed solely based on the LGE-MRI results. During 1-year follow-up after second ablation, 67% patients in group 1 and 64% patients in group 2 were free from recurrence (log-rank, P =1.000). In group 2, 64% in the electroanatomically guided and 65% in the LGE-MRI dechanneling group were free from recurrence (log-rank, P =0.900). Conclusions: Anatomic targeting of LGE-MRI–detected gaps and superficial atrial scar is feasible and effective to treat recurrent arrhythmias post-AF ablation. Homogenization of existing scar is the appropriate treatment for recurrent AF, whereas dechanneling of existing isthmi seems the right approach for patients recurring with AT.