Unidirectional block on the mitral isthmus during radiofrequency application for perimitral atrial tachycardia

• Published in: Journal of arrhythmia Vol. 29; no. 5; pp. 270 - 274
• Main Authors: Yamashita, Seigo, MD, Yamane, Teiichi, MD, Matsuo, Seiichiro, MD, Ito, Keiichi, MD, Narui, Ryohsuke, MD, Hioki, Mika, MD, Tanigawa, Shin-ichi, MD, Tokuda, Michifumi, MD, Inada, Keiichi, MD, Date, Taro, MD, Sugimoto, Ken-ichi, MD, Yoshimura, Michihiro, MD
• Format: Journal Article
• Language: English
• Published: Tokyo Elsevier B.V 01.10.2013; John Wiley & Sons, Inc; Wiley
• Subjects: Ablation; Ablation (Surgery); Adenosine triphosphate; Atrial fibrillation; Bepridil; Cardiac arrhythmia; Cardiovascular; Catheter ablation; Catheters; Electrocardiography; Electrodes; Heart rate; Paroxysmal tachycardia; Patients; Perimitral tachycardia; Unidirectional conduction block; Japan; Perimitral tachycardia; Catheter ablation; Unidirectional conduction block
• ISSN: 1880-4276; 1883-2148
• DOI: 10.1016/j.joa.2012.12.006

Abstract We present the case of a patient who developed regular, narrow QRS tachycardia after ablation for long-standing persistent atrial fibrillation. During the electrophysiological study, this tachycardia was diagnosed as macroreentrant atrial tachycardia circulating around the mitral annulus. Catheter ablation was performed to treat the tachycardia by targeting the linear region between the annulus and the left inferior pulmonary vein. Although linear radiofrequency application along the mitral isthmus (MI) line resulted in the termination of this tachycardia, a unidirectional conduction block was observed through the MI. Bidirectional conduction block was subsequently achieved by delivering supplemental radiofrequency energies at the gap on the MI.