Strategies for Repeat Ablation for Atrial Fibrillation: A Multicentre Comparison of Non-Pulmonary Vein versus Pulmonary Vein Target Ablation

Predictors of late recurrence after second catheter ablation for persistent atrial fibrillation

BACKGROUND

Little has been reported on the predictors of late recurrence (LR) after second radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF).

OBJECTIVE

This study aimed to identify the predictors of LR after second RFCA in patients with persistent AF.

METHODS

We retrospectively analyzed 123 patients who underwent a second RFCA because of LR after the initial RFCA for persistent AF. LR was defined as a recurrence of atrial tachyarrhythmia >3 months after the ablation procedure. The initial RFCA included pulmonary vein isolation alone or pulmonary vein isolation plus cavotricuspid isthmus block. The predictors of LR were evaluated by the Cox proportional hazards model.

RESULTS

In the univariate analysis, elevated brain natriuretic peptide levels, absence of pulmonary vein reconnections at the beginning of the second RFCA, and presence of early recurrence (ER, defined as a recurrence of atrial tachyarrhythmia within 3 months) after the second RFCA were associated with LR (P = .025, P = .018, and P < .001, respectively). The multivariate analysis revealed that absence of pulmonary vein reconnections and presence of ER were independent predictors of LR after the second RFCA (P = .004 and P < .001, respectively).

CONCLUSION

Absence of pulmonary vein reconnections and presence of ER were strongly associated with LR after the second RFCA in patients with persistent AF.

Silent pulmonary veins at redo ablation for atrial fibrillation: Implications and approaches

BACKGROUND

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. Despite promising success rates, redo ablation is sometimes required. At redo, PVs may be found to be isolated (silent) or reconnected. We studied patients with silent vs reconnected PVs at redo and analysed associations with adverse outcomes.

METHODS

Patients undergoing redo AF ablations between 2013 and 2019 at our institution were included and stratified into silent PVs or reconnected PVs. The primary outcome was a composite of further redo ablation, non-AF ablation, atrioventricular nodal ablation, and death. Secondary outcomes included arrhythmia recurrence.

RESULTS

A total of 467 patients were included with mean 4.6 ± 1.7 years follow-up, of whom 48 (10.3%) had silent PVs. The silent PV group had had more often undergone >1 prior ablation (45.8% vs 9.8%; p<0.001), had more persistent AF (62.5% vs 41.1%; p=0.005) and had more non-PV ablation performed both at prior ablation procedures and at the analysed redo ablation. The primary outcome occurred more frequently in those with silent PVs (25% vs 13.8%; p=0.053). Arrhythmia recurrence was also more common in the silent PV group (66.7% vs 50.6%; p=0.047). After multivariable adjustment, female sex (aHR 2.35 [95% CI 2.35-3.96]; p=0.001) and ischaemic heart disease (aHR 3.21 [95% CI 1.56-6.62]; p=0.002) were independently associated with the primary outcome, and left atrial enlargement (aHR 1.58 [95% CI 1.20-2.08]; p=0.001) and >1 prior ablation (aHR 1.88 [95% CI 1.30-2.72]; p<0.001) were independently associated with arrhythmia recurrence. Whilst a finding of silent PVs was not itself significant after multivariable adjustment, this provides an easily assessable parameter at clinically indicated redo ablation which informs the clinician of the likelihood of a worse future prognosis.

CONCLUSIONS

Patients with silent PVs at redo AF ablation have worse clinical outcomes.

Electrogram morphology recurrence guided catheter ablation for repeat ablation of persistent atrial fibrillation

BACKGROUND

There are no standard mapping approaches for patients with persistent atrial fibrillation (PeAF), particularly after failed prior catheter ablation (CA). In this study, we assess the feasibility of using Electrogram Morphology Recurrence (EMR) to guide ablation.

METHODS

Ten patients with recurrent PeAF after prior CA underwent detailed mapping of both atria during PeAF using the PentaRay (4 mm interelectrode spacing) and 3D mapping with CARTO. At each site, 15 s recordings were made. Custom software identified each electrogram and cross-correlation was used to identify the most recurrent electrogram morphology from which the % recurrence and cycle length of the most repeatable morphology (CLR) was calculated. Sites of shortest CLR and sites within 5 ms of shortest CLR with recurrence ≥ 80% were used to inform CA strategy.

RESULTS

A mean of 342.9 ± 131.9 LA and 328.6 ± 91.5 RA sites were recorded per patient. Nine had PV reconnection. Shortest CLR sites guided ablation in 6/10 patients while 1 patient failed to fulfill shortest CLR criteria, and another 3 did not undergo CA guided by shortest CLR due to operator preference. On 12-month follow-up, all 4 patients without shortest CLR guided CA had recurrent PeAF. Of the 6 patients with shortest CLR guided CA, 5 patients did not have recurrent PeAF (p = 0.048), although 1 had paroxysmal AF and 2 had atypical atrial flutter.

CONCLUSION

EMR is a feasible, novel technique to guide CA in patients with PeAF. Further evaluation is needed to provide an electrogram-based method for mapping guided targeted ablation of key areas.