Background: Recently, radiofrequency catheter ablation (RFCA) has become an important treatment strategy for atrial fibrillation (AF). During this procedure, achieving first-pass pulmonary vein (PV) isolation — PV isolation in which no residual conduction gap remains following initial circumferential lesion is created around the PV — has proven to lead better results in terms of AF recurrence. Although various risk factors for the creation of residual conduction gap have been proposed, the relationship between the transseptal puncture location on fossa ovalis and first-pass PV isolation success rate has not been clarified. Therefore, we investigate the relationship through this investigation. Methods: Overall, 102 consecutive patients who had undergone their first RFCA for AF were included. These patients were divided based on the transseptal puncture location (infero-anterior, infero-posterior, supero-anterior, and supero-posterior), which was confirmed by imaging of three-dimensional structure of the anatomical fossa ovalis creating intracardiac echocardiography. The relationship between transseptal puncture location and the first-pass PV isolation success rate was analyzed. Results: Among all 102 patients, the number of transseptal puncture locations located in infero-anterior, infero-posterior, supero-anterior, and supero-posterior were 26, 61, 6, and 9 respectively. Among these, first-pass PV isolation success rate in the infero-posterior group exhibited the highest 79% (48/61 patients) compared to that in other locations [infero-anterior 61% (16/26 patients), supero-anterior 33% (2/6 patients), and supero-posterior 44% (4/9 patients); P=0.02]. Regarding ablation parameters, although the ablation index was not significantly different between each group (infero-anterior 401.6±7.6, infero-posterior 401.9±5.2, supero-anterior 397.5±4.7, and supero-posterior 398.6±5.3, P = 0.176). The P-vector, which represents insufficient catheter contact, was significantly observed lower frequency in the infero-posterior group (8.6%; P < 0.01) than in the other groups. Conclusion: The transseptal puncture location in PV isolation is an important factor to achieve first-pass PV isolation, and it might affect AF recurrence.

Dr Tsujita has received honoraria from AMI Co., Ltd., Bayer Yakuhin, Ltd., Bristol-Myers K.K., EA Pharma Co.,Ltd., Mochida Pharmaceutical Co., Ltd., and scholarship fund from AMI Co., Ltd., Bayer Yakuhin, Ltd., Boehringer Ingelheim Japan, Chugai Pharmaceutical Co, Ltd., Daiichi Sankyo Co., Ltd., Edwards Lifesciences Corporation, Johnson & Johnson K.K., Ono Pharmaceutical Co., Ltd., Otsuka Pharmaceutical Co.,Ltd., Takeda Pharmaceutical Co., Ltd., and honoraria from Amgen K.K., Bayer Yakuhin, Ltd., Daiichi Sankyo Co., Ltd., Kowa Pharmaceutical Co. Ltd., Novartis Pharma K.K., Otsuka Pharmaceutical Co.,Ltd., Pfizer Japan Inc., and belongs to the endowed departments donated by Abbott Japan Co., Ltd., Boston Scientific Japan K.K., Fides-one, Inc., GM Medical Co., Ltd., ITI Co.,Ltd., Kaneka Medix Co., Ltd., Nipro Corporation, Terumo Co, Ltd., Abbott Medical Co., Ltd., Cardinal Health Japan, Fukuda Denshi Co., Ltd., Japan Lifeline Co.,Ltd., Medical Appliance Co., Ltd., Medtoronic Japan Co., Ltd.

This study is retrospective study. Therefore, no clinical trial ID was assigned.

This investigation was supported by the Johnson & Johnson Medical Research Grant and Takeda Science Foundation.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study adhered to the Declaration of Helsinki principles and received approval from the Institutional Review Board and Ethics Committee of Kumamoto University (approval number 2772).

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The datasets used and analyzed during the current study available from the corresponding author on reasonable request.