One Electrogram-Tracing Tells All: what is the mechanism of this supraventricular tachycardia?Moyuru Hirata, MD*, Yuji Wakamatsu, MD*, Koichi Nagashima, MD, PhD*, Sayaka Kurokawa, MD, PhD*, Naoto Otsuka, MD*, Seina Yagyu, MD*, Shu Hirata, MD*, Toshiko Nakai, MD, PhD*, Yasuo Okumura, MD, PhD*.*Division of Cardiology, Department of Medicine, Nihon University School of Medicine, Tokyo, JapanCorrespondenceKoichi Nagashima, MD, PhD; Division of Cardiology, Department of Medicine, Nihon University School of Medicine, 30-1 Ohyaguchi-kamicho, Itabashi-ku, Tokyo 173-8610, JapanTel: +81-3-3972-8111Fax: +81-3-3972-1098E-mail: [email protected] word count: 1036 words, 2 FiguresFunding: (None)Disclosures: (None)The work described was supported by departmental resources only.Keywords: narrow QRS tachycardia, atrioventricular nodal reentrant tachycardia, accessary pathway.