Long-Term Impact of Additional Ablation After Pulmonary Vein Isolation: Results From EARNEST-PVI Trial

Abstract

Background An optimal strategy for left atrial ablation in addition to pulmonary vein isolation (PVI) in patients with persistent atrial fibrillation (AF) has not been determined. Methods and Results We conducted an extended follow-up of the multicenter randomized controlled EARNEST-PVI (Efficacy of Pulmonary Vein Isolation Alone in Patients With Persistent Atrial Fibrillation) trial, which compared 12-month rhythm outcomes in patients with persistent AF between patients randomized to a PVI-alone strategy (n=248) or PVI-plus strategy (n=248; PVI followed by left atrial additional ablation, including linear ablation or ablation targeting areas with complex fractionated electrograms). The present study extended the follow-up period to 3 years after enrollment. Outcomes were compared not only between randomly allocated groups but also between on-treatment groups categorized by actually created ablation lesions. Recurrence rate of AF or atrial tachycardia (AT) was lower in the randomly allocated to PVI-plus group than the PVI-alone group (29.0% versus 37.5%, P=0.036). On-treatment analysis revealed that patients with PVI+linear ablation (n=205) demonstrated a lower AF/AT recurrence rate than those with PVI only (26.3% versus 37.8%, P=0.007). In contrast, patients with PVI+complex fractionated electrograms ablation (n=37) had an AF/AT recurrence rate comparable to that of patients with PVI only (40.5% versus 37.8%, P=0.76). At second ablation in 126 patients with AF/AT recurrence, ATs excluding common atrial flutter were more frequent in patients with PVI+linear ablation than in those with PVI only (32.6% versus 5.7%, P<0.0001). Conclusions Left atrial ablation in addition to PVI was efficacious during 3-year follow-up. Linear ablation was superior to other ablation strategies but may increase iatrogenic ATs. Registration URL: http://www.umin.ac.jp/ctr/index-j.htm; Unique identifier: UMIN000019449.

Keywords: left atrial ablation; linear ablation; persistent atrial fibrillation; recurrence.

Figure 1. Patient flow chart.

Patients were randomly allocated to PVI‐alone (n=248) and PVI‐plus (n=245) ablation strategies. All patients allocated to the PVI‐alone strategy did not undergo additional left atrial ablation. Patients allocated to the PVI‐plus strategy underwent PVI only (n=3), PVI+Line (n=205), and PVI+CFAE (n=37). In the PVI+Line group, major ablation lesion sets were (1) posterior mitral line, roof line, and bottom line (n=101); (2) posterior mitral line and roof line (n=67); and (3) anterior mitral line and roof line (n=29). AF indicates atrial fibrillation; CFAE, ablation targeting areas with complex fractionated atrial electrograms; Line, linear ablation; and PVI, pulmonary vein isolation.

Figure 2. AF/AT recurrence‐free survival curves.

Patients randomly allocated to the PVI‐plus group showed higher AF/AT recurrence‐free survival rates than the PVI‐alone group after the initial (A) and multiple ablations (B). On‐treatment analysis revealed that PVI+Line group demonstrated higher AF/AT recurrence‐free survival rate than the PVI‐only group after the initial (C) and multiple ablations (D). AF indicates atrial fibrillation; AT, atrial tachycardia; CFAE, ablation targeting areas with complex fractionated atrial electrograms; Line, linear ablation; and PVI, pulmonary vein isolation.

Figure 3. Recurrent types of atrial arrhythmias.

Proportions of each type of recurrent atrial arrhythmia during 3‐year follow up are shown. Comparisons between randomly allocated groups (A through C) demonstrated that AF/AT recurrence and AF recurrence were less frequent in patients with PVI plus than in those with PVI alone. On‐treatment analyses (D through F) showed that the PVI+Line group had less AF/AT recurrence and AF recurrence than the PVI‐only group. AF indicates atrial fibrillation; AT, atrial tachycardia; CFAE, ablation targeting areas with complex fractionated atrial electrogram; Line, linear ablation; and PVI, pulmonary vein isolation.

Figure 4. Forest plots displaying impact of linear ablation in addition to PVI on AF/AT recurrence stratified according by subgroups.

Hazard ratios of AF/AT recurrence in the PVI+Line group compared with the PVI‐only group are shown stratified according to specific patient populations. PVI+linear ablation was more effective than PVI only among patients aged >65 years old and those with hypertension. AF indicates atrial fibrillation; AT, atrial tachycardia; and PVI, pulmonary vein isolation.

Figure 5. Observation of LAT during the second ablation.

Observation of LAT included any mappable ATs such as spontaneously developed AT, programmed stimulation‐induced AT, and beta stimulant drug‐induced AT. LAT was defined as AT where the entire or a portion of tachycardia circuit was located within the left atrium. LATs were more frequently observed in the randomly allocated to PVI‐plus group than in the PVI‐alone group (A). On‐treatment analysis demonstrated that the PVI+Line group experienced more frequent LATs than the PVI‐only group (B). There was no difference in LAT observation rate between linear ablation lesion sets in the PVI+Line group (C). ant indicates anterior; AT, atrial tachycardia; Btm, bottom line; CFAE, ablation targeting areas with complex fractionated electrocardiograms; LAT, left atrial tachycardia; Line, linear ablation; Mlt, mitral line; Pst, posterior; PVI, pulmonary vein isolation; and Rf, roof line.