A case of an incision-related single-loop intra-atrial reentrant tachycardia showing an eccentric atrial activation sequence and widely separate potentials resembling a double-loop reentry; its mechanism and analysis

Introduction A supraventricular reentrant tachycardia (SVT) appearing after cardiac surgery is known to have a complicated reentrant circuit, such as a figure-8 pattern based on a double-loop reentry using both an incisional line and the cavotricuspid isthmus (CTI). In order to determine the reentrant circuit of the SVT, detailed mapping using a 3-dimensional (3-D) electroanatomical mapping system during the tachycardia is essential. We present an incision-related single-loop reentrant SVT, resembling a double-loop reentry, which was correctly diagnosed by analyzing the special positional relationship between the multipolar electrode catheter and the incision.