Kasai Yuhei, Iitsuka Kizuku, Morita Junji, Kitai Takayuki
Department of Cardiology, Sapporo Heart Center, Sapporo Cardiovascular Clinic, Sapporo, Japan.
Indian Pacing Electrophysiol J. 2025 Jan-Feb;25(1):32-36. doi: 10.1016/j.ipej.2024.10.002. Epub 2024 Oct 5.
Radiofrequency (RF) catheter ablation is the primary treatment for cavotricuspid isthmus (CTI)-dependent atrial flutter (AFL), with cryothermal energy as an alternative. While cryoablation offers comparable effectiveness and safety to RF ablation, it poses a risk of coronary artery spasm leading to ST-elevation. This case report presents a 65-year-old man with drug-refractory atrial fibrillation (AF) and AFL undergoing cryothermal CTI ablation guided by intracardiac echocardiography (ICE). During the procedure, two distinct ST-elevation episodes were observed. The first episode coincided with the pull-down of the cryoablation catheter, potentially resulting in coronary compression, as indicated by ICE, and was rapidly resolved by discontinuing the freezing process. The second episode, occurring without active freezing, was attributed to coronary artery spasm and resolved with intracoronary nitroglycerin administration. During the second episode, emergent right coronary angiography confirmed total occlusion in the segment 4 AV adjacent to the region where cryoablation was performed, which fully resolved post-nitroglycerin. This report underscores the dual mechanisms of ST-elevation-coronary artery compression and spasm-during cryothermal CTI ablation, highlighting the critical role of ICE in enhancing procedural safety.
射频（RF）导管消融术是三尖瓣峡部（CTI）依赖性心房扑动（AFL）的主要治疗方法，冷冻热能消融可作为替代方案。虽然冷冻消融与射频消融具有相当的有效性和安全性，但它存在导致冠状动脉痉挛进而引起ST段抬高的风险。本病例报告介绍了一名65岁患有药物难治性心房颤动（AF）和AFL的男性，在心脏内超声心动图（ICE）引导下接受冷冻CTI消融术。术中观察到两次明显的ST段抬高发作。第一次发作与冷冻消融导管下拉同时发生，心脏内超声心动图显示这可能导致冠状动脉受压，通过停止冷冻过程迅速得到缓解。第二次发作在未进行主动冷冻时发生，归因于冠状动脉痉挛，通过冠状动脉内给予硝酸甘油得以缓解。在第二次发作期间，急诊右冠状动脉造影证实，在进行冷冻消融区域相邻的4 AV节段完全闭塞，使用硝酸甘油后完全缓解。本报告强调了冷冻CTI消融术中ST段抬高的双重机制——冠状动脉受压和痉挛，突出了心脏内超声心动图在提高手术安全性方面的关键作用。
