Nodera Minoru, Kaneshiro Takashi, Murota Sadahiro, Yamada Shinya, Oikawa Masayoshi, Takeishi Yasuchika
Department of Cardiovascular Medicine Fukushima Medical University Fukushima Japan.
Department of Arrhythmia and Cardiac Pacing Fukushima Medical University Fukushima Japan.
J Arrhythm. 2025 Jul 31;41(4):e70159. doi: 10.1002/joa3.70159. eCollection 2025 Aug.
Cryoablation is an alternative to radiofrequency ablation for the treatment of cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL). However, the anatomical features that make achieving a CTI conduction block using cryoablation challenging remain unclear.
This study included 100 consecutive patients who underwent CTI cryoablation for AFL. Patients were divided into two groups: the first-pass group, in which first-pass CTI conduction block was achieved ( = 72) and the non-first-pass group, in which it was not achieved ( = 28). We analyzed the anatomical features and the temperature changes of the catheter during the first sequential CTI cryoablation.
The distance from the CTI to the right coronary artery (RCA) in the first-pass group was significantly longer than that in the non-first-pass group ( < 0.001). The time to reach nadir freezing temperature in the ventricular side of the CTI was significantly shorter in the first-pass group than in the non-first-pass group ( < 0.001). The time to reach nadir freezing temperature at the ventricular side of the CTI correlated inversely with the distance from the CTI to the RCA ( = -0.410, < 0.001). The distance from the CTI to the RCA was the only significant factor associated with achieving first-pass CTI conduction block (odds ratio, 4.801, < 0.001).
The distance from the CTI to the RCA was significantly associated with achieving first-pass CTI conduction block by cryoablation. The warming effect of the RCA blood flow might prevent the CTI conduction block during cryoablation.
冷冻消融是治疗三尖瓣峡部（CTI）依赖性心房扑动（AFL）的一种替代射频消融的方法。然而，使用冷冻消融实现CTI传导阻滞具有挑战性的解剖学特征仍不清楚。
本研究纳入了100例连续接受CTI冷冻消融治疗AFL的患者。患者分为两组：首次通过组，即实现首次通过CTI传导阻滞的患者（n = 72）和非首次通过组，即未实现首次通过CTI传导阻滞的患者（n = 28）。我们分析了首次序贯CTI冷冻消融过程中的解剖学特征和导管温度变化。
首次通过组中CTI至右冠状动脉（RCA）的距离显著长于非首次通过组（P < 0.001）。CTI心室侧达到最低冷冻温度的时间在首次通过组显著短于非首次通过组（P < 0.001）。CTI心室侧达到最低冷冻温度的时间与CTI至RCA的距离呈负相关（r = -0.410，P < 0.001）。CTI至RCA的距离是与实现首次通过CTI传导阻滞相关的唯一显著因素（优势比，4.801，P < 0.001）。
CTI至RCA的距离与通过冷冻消融实现首次通过CTI传导阻滞显著相关。RCA血流的升温效应可能会在冷冻消融过程中阻止CTI传导阻滞。
