B-PO02-077 OUTCOMES OF LEFT ATRIAL POSTERIOR WALL ISOLATION IN CONJUNCTION WITH PULMONARY VEIN ISOLATION FOR PAROXYSMAL ATRIAL FIBRILLATION

Abstract

The posterior wall of the left atrium harbors similar embryologic, arrhythmogenic and electrophysiologic properties to the pulmonary veins. Several prior studies have shown that in patients with persistent AF, addition of posterior wall isolation (PWI) may reduce atrial arrhythmia recurrence. No data on PWI in paroxysmal AF (pAF) patients is available to date. To evaluate the outcome of PWI in addition to pulmonary vein isolation (PVI) on atrial arrhythmia recurrence in patients undergoing high power short duration ablation for pAF. Registry of all patients with pAF and normal left atrial voltage (>0.5 mV) undergoing first-time radiofrequency ablation from November 1, 2018 to November 15, 2019. Endpoints included recurrence of atrial arrhythmia including AF, atrial tachycardia (AT) or atrial flutter (AFL). A total of 321 patients were studied, 214 in the PVI only group and 107 in the PWI+PVI group with an average follow-up of 372 ± 126 days. Baseline clinical and echocardiographic characteristics were similar between groups. 50W lesions were delivered in all locations. Arrhythmia recurred in 18.2% of patients in the PVI group and 16.8% in the PWI+PVI group (p=0.58). At one year, recurrence was 14.0% in the PVI group and 15.0% in the PWI+PVI group (p=0.96). Time to arrhythmia recurrence was similar in both PWI+PVI and PVI groups (237 ± 115 days vs. 279 ± 138 days, p=0.250). There was a trend for lower AT/AFL recurrence in the PWI group (3.7% vs. 7.9%, p=0.31). Need for carina lesions was associated with recurrence in the PVI group (17.9% vs. 6.3%, p=0.04) and longer RF time was associated with recurrence in the PWI+PVI group (34.7 ± 14.1 min vs. 27.3 ± 9.0 min, p=0.025). There was no significant increase in procedural or ablation time in the PWI+PVI group. Complication rates were low in both groups (2 patients in PVI group and 1 patient in the PWI+PVI group). The addition of PWI to PVI in pAF patients undergoing ablation did not reduce the frequency of atrial arrhythmia recurrence. We observe a trend towards less AT/AFL recurrence with addition of PWI to PVI. The addition of PWI reduced the impact of carinal residual activity after PVI on arrhythmia recurrence. This warrants further study in a prospective trial.