Importance of Terminating Pulmonary Vein Fibrillation for Complete Pulmonary Vein Isolation

A 64-year-old woman was referred for ablation of paroxysmal atrial fibrillation (AF). She had hypertension and normal left atrium (LA; 31 mm). Circumferential pulmonary vein (PV) isolation (PVI) was performed. After ablation, PV fibrillation (PVF) was confined within the left PV. Cardioversion was performed 3 times to terminate the PVF. After cardioversion, PV potentials, that is, slow entrance conduction (from 4:1 to 1:1), were noted and confirmed (Figure; Supplementary Figure; Supplementary Movie). Reinforcement ablation was performed to block the LA-PV conduction completely. During a 12-month follow-up, the patient was free of arrhythmia without anti-arrhythmics.

Figure.

Surface and intracardiac electrograms recorded using a coronary sinus catheter, a Lasso catheter (in the left superior pulmonary vein [PV]) and the ablation catheter. Confined PV fibrillation (PVF) was confirmed while the atrium was in sustained sinus rhythm (SR), but after direct current cardioversion (CV) terminating the confined PVF, PV potential (PVP), that is, slow entrance conduction from the left atrium (LA) to the PV, was observed.

Bidirectional and durable LA-PV block is important for AF ablation.¹ Generally, confined PVF is an indicator of arrhythmogenic trigger and is accepted as the endpoint for PVI.² In this case, confined PVF and sustained sinus rhythm in the atrium indicated PV-LA exit block, but after PVF termination, LA-PV entrance conduction was observed. Furthermore, cardioversion was performed 3 times to terminate PVF, before the entrance conduction was observed. Therefore, confined PVF may indicate only the exit block and not the entrance block; that is, confined PVF may not be sufficient for complete PVI and may lead to acute and/or chronic PV reconnection. In conclusion, it is important to terminate PVF to ensure complete PVI.

Disclosures

The authors declare no conflicts of interest.

Supplementary Files

Please find supplementary file(s);

http://dx.doi.org/10.1253/circj.CJ-19-0679

References

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• 2.   Chen S, Wu H, Chen G, Zhang F, Meng W, Yan Y, et al. Clinical implications of and factors influencing dissociated pulmonary vein potentials. J Cardiol 2015; 66: 155–160.