title: Multiple focal and macroreentrant left atrial tachycardias originating from a spontaneous scar at the contiguous aorta-left atrium area in a patient with hypertrophic cardiomyopathy: a case report.
abstract: Spontaneous scar-related left atrial tachycardia (AT) is a rare arrhythmia. We describe a patient with hypertrophic cardiomyopathy (HCM) who developed multiple, both focal and macroreentrant left ATs associated with a spontaneous scar located at the aorta-left atrium (LA) contiguous area.
  
  
  
  A 65-year-old man with HCM complained of palpitations. Twelve-lead electrocardiogram showed narrow QRS tachycardia with 2:1 atrioventricular conduction. Two sessions of radiofrequency ablation (RFA) were required to eliminate all left ATs. In the first session, 3-dimensional electroanatomical mapping fused with the image constructed by multi-detector computed tomography showed a clockwise macroreentrant AT (AT1) associated with a low-voltage or dense scar area located along the aorta-LA contiguous area. AT1 was eliminated by RFA to the narrow isthmus with slow conduction velocity within the scar. Additional ATs (AT2-AT4) occurred 1 month after the first ablation. In the second session, AT2 and AT3 were identified as focal ATs with centrifugal propagation and few accompanying fragmentations, and AT4 as a macroreentrant AT with features similar to AT1. AT2 and AT3 were successfully eliminated by performing RFA to the earliest activation site, and AT4 was terminated by performing RFA to the narrow isthmus with slow conduction velocity. No ATs have recurred for 11 months after these RFAs. Interestingly, the substrate for all left ATs was associated with the aorta-LA contiguous area.
  
  
  
  To our knowledge, this is the first case of multiple, both focal and macroreentrant left ATs associated with a contiguous aorta-LA spontaneous scar area in a patient with HCM.
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan. kamisamakaranookurimono@gmail.com.
authors.forename: Kyoichiro
authors.identifier: 0000-0001-8839-0186
authors.initials: K
authors.lastname: Yazaki
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Ajiro
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Mori
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Tsukamoto
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Saito
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Mizobuchi
authors.affiliation: Department of Cardiology, National Hospital Organization Yokohama Medical Center, 3-60-2 Harajuku, Totsuka-ku, Yokohama-shi, Kanagawa, 245-8575, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Iwade
mesh_terms: D000200:Action Potentials; D000368:Aged; D001011:Aorta / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D016279:Atrial Function, Left; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications* / Q000175:diagnosis; D017115:Catheter Ablation; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D006325:Heart Atria / Q000473:pathology / Q000503:physiopathology* / Q000601:surgery; D006339:Heart Rate; D006801:Humans; D008297:Male; D061330:Multidetector Computed Tomography; D011237:Predictive Value of Tests; D013617:Tachycardia, Supraventricular / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome
keywords: 3-D electroanatomical mapping; Atrial tachycardia; Case report; Contiguous aorta-left atrium area; Hypertrophic cardiomyopathy; Spontaneous scar