Although the anterior and posterior boundaries of cavotricuspid isthmus-dependent atrial flutter (AFL) are reported to be located at the tricuspid annulus and sinus venosa region or crista terminalis, the exact upper turnaround point of the AFL circuit remains unclear. The aim of this study was to determine the upper turnaround site of the AFL circuit by means of three-dimensional (3D) mapping and entrainment pacing.
Division of Cardiology, Department of Medicine, Nihon University School of Medicine, 30-1 Ohyaguchi-kami machi, Itabashi-ku, Tokyo 173-8610, Japan. yasuwo128@yahoo.co.jp
