Yoshida Akira, Oka Takafumi, Sekihara Takayuki, Nakano Tomoaki, Sakata Yasushi
Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
Eur Heart J Case Rep. 2025 Jul 15;9(8):ytaf334. doi: 10.1093/ehjcr/ytaf334. eCollection 2025 Aug.
Cavotricuspid isthmus (CTI) is a part of the re-entrant circuit of atrial flutter (AFL), and its linear ablation is the method of choice for treating CTI-dependent AFL. We describe our experience of a case of multiple atrial tachycardias (ATs) originating from the CTI aneurysm and the challenges encountered during its electrophysiological management.
The patient, a 61-year-old woman with hereditary non-polyposis colorectal cancer, presented with recurrent supraventricular tachycardia resistant to conventional treatment with anti-arrhythmic medication and electrical cardioversion. The 12-lead electrocardiogram finding suggested CTI-dependent AFL. In the initial ablation session, right atrium angiography revealed the presence of a CTI aneurysm. We completed the CTI bidirectional block, but AT recured immediately. Multiple focal ATs originated around tricuspid valve annulus, and CTI-dependent re-entrant AT was induced in the second session. Since multiple fractionated potential was observed in the CTI aneurysm during the AT mapping, we decided to create electrical isolation of the CTI aneurysm by lateral and septal CTI block lines. After CTI aneurysm isolation, ATs were eliminated. After 3 months, ATs recured. The reconnected lateral CTI block line was re-completed in the third session, and CTI re-isolation was achieved. Since the third session, there were no recurrent ATs.
In this case, the CTI aneurysm was crucial and underlies the mechanism of multiple ATs. Electrical isolation of the CTI aneurysm was effective. This case emphasizes the importance of detailed anatomical assessment, particularly in patients with unusual CTI structures, and illustrates the successful use of novel mapping technologies.
腔静脉-三尖瓣峡部（CTI）是心房扑动（AFL）折返环的一部分，其线性消融是治疗CTI依赖性AFL的首选方法。我们描述了一例源自CTI动脉瘤的多种房性心动过速（ATs）病例的经验以及在其电生理管理过程中遇到的挑战。
该患者为一名61岁患有遗传性非息肉病性结直肠癌的女性，表现为复发性室上性心动过速，对常规抗心律失常药物治疗和电复律均无效。12导联心电图结果提示CTI依赖性AFL。在初次消融过程中，右心房造影显示存在CTI动脉瘤。我们完成了CTI双向阻滞，但AT立即复发。多个局灶性AT起源于三尖瓣环周围，并且在第二次手术中诱发了CTI依赖性折返性AT。由于在AT标测期间在CTI动脉瘤中观察到多个碎裂电位，我们决定通过外侧和间隔CTI阻滞线对CTI动脉瘤进行电隔离。CTI动脉瘤隔离后，AT消失。3个月后，AT复发。在第三次手术中重新完成了重新连接的外侧CTI阻滞线，并实现了CTI再次隔离。自第三次手术后，未再出现AT复发。
在本病例中，CTI动脉瘤至关重要，是多种AT机制的基础。CTI动脉瘤的电隔离是有效的。该病例强调了详细解剖评估的重要性，特别是对于具有异常CTI结构的患者，并说明了新型标测技术的成功应用。
