A Case of Lateral Cavotricuspid Isthmus (CTI) Reentrant Atrial Tachycardia (AT) Showing ECG Similar to Common Atrial Flutter (AFL) without Prior Ablation

概要

論文の詳細を見る
An 81-year-old male had a supraventricular tachycardia (SVT) with a saw-tooth pattern ECG similar to common AFL in inferior leads and constrictive pericarditis without prior cardiac surgery or radiofrequency ablation (RFA). EPS was performed using Halo, coronary sinus (CS) and His bundle catheters with NavX system and RFA using an irrigated 4-mm-tip catheter. 3-D electroanatomical activation mapping around the tricuspid valve during the SVT induced by atrial programmed stimulation depicted that the tachycardia was not AFL but focal AT centrifugally spreading from the lateral CTI. Next, entrainment pacing during the AT was performed from multiple atrial sites, so that only a post pacing interval of the earliest site was almost identical to the tachycardia cycle length (TCL) of approximate 350 ms; however, values of any other sites, such as ostial and distal CS, mid and high lateral right atrium (RA) and atrial septum, were longer over 50 ms than that of the TCL. Initial RFA at the earliest site could terminate the AT and render its inducibility impossible. Stimulation at the proximal CS and lateral RA after the ablation indicated that no bidirectional block in the CTI had been completed yet. Therefore, this reentrant AT was confirmed to be confined within the lateral CTI.