OBJECTIVETo investigate the mechanism and re-ablation strategy of recurrent atrial tachyarrhythmia (ATA) following circumferential ablation of pulmonary veins (PV) in patients with atrial fibrillation (AF).

METHODSFifteen patients with recurrent ATA following first AF ablation procedure were included in this study. Under CARTO guidance, PVs were remapped and ablated subsequently for relapse of left atrium to PV conduction. The whole atrium was then remapped and individualized ablation was made to eliminate inducible ATA.

RESULTSLeft atrium to PV conduction relapses were evidenced in 14 patients. After re-ablation, there were no inducible ATA in 9 patients, inducible left atrial macro-reentry tachycardia in 3 patients and all were terminated by further linear ablation on the roof and left atrial isthmus, inducible atrial focal tachycardia from left atrial isthmus in 1 patient and was eliminated after additional focal ablation, inducible right atrial macro-reentry tachycardia in 2 patients and were eliminated by right isthmus linear ablation. During 1 - 16 (5.5 +/- 4.4) months follow-up, ATA was disappeared in 13 patients and reduced in another 2 patients.

CONCLUSIONSRelapse of left atrium to PV conduction is one of the main mechanisms for postablation ATA in patients with AF. Atrial macro-reentry tachycardia and focal atrial tachycardia were less common mechanisms for postablation ATA. Re-ablation focused on closing the PV gaps and additional individualized focal and lineal ablation strategies were helpful for treating postablation ATA in AF patients.