Substrate modification by pulmonary vein isolation and left atrial linear ablation in patients with persistent atrial fibrillation: its impact on complex-fractionated atrial electrograms.

UNLABELLED: PV and Linear Ablation for CFAEs.

INTRODUCTION

Linear ablations in the left atrium (LA), in addition to pulmonary vein (PV) isolation, have been demonstrated to be an effective ablation strategy in patients with persistent atrial fibrillation (PsAF). This study investigated the impact of LA linear ablation on the complex-fractionated atrial electrograms (CFAEs) of PsAF patients.

METHODS AND

RESULTS

A total of 40 consecutive PsAF patients (age: 54 ± 10 years, 39 males) who underwent catheter ablation were enrolled in this study. Linear ablation of both roofline between the right and left superior PVs and the mitral isthmus line joining from the mitral annulus to the left inferior PV were performed following PV isolation during AF. High-density automated CFAE mapping was performed using the NAVX, and maps were obtained 3 times during the procedure (prior to ablation, after PV isolation, and after linear ablations) and were compared. PsAF was terminated by ablation in 13 of 40 patients. The mean total LA surface area and baseline CFAEs area were 120.8 ± 23.6 and 88.0 ± 23.5 cm(2) (74.2%), respectively. After PV isolation and linear ablations in the LA, the area of CFAEs area was reduced to 71.6 ± 22.6 cm(2) (58.7%) (P < 0.001) and 44.9 ± 23.0 cm(2) (39.2%) (P < 0.001), respectively. The LA linear ablations resulted in a significant reduction of the CFAEs area percentage in the region remote from ablation sites (from 56.3 ± 20.6 cm(2) (59.6%) to 40.4 ± 16.5 cm(2) (42.9%), P < 0.0001).

CONCLUSION

Both PV isolation and LA linear ablations diminished the CFAEs in PsAF patients, suggesting substrate modification by PV and linear ablations. (J Cardiovasc Electrophysiol, Vol. 23, pp. 962-970, September 2012).