[Reentrant tachyarrhythmia related to anatomic scar or isthmus]

Abstract

Macroreentrant tachyarrhythmia rotating around an atrioventricular valve annulus or an atriotomy scar occurs after myocardial infarction or surgical repair of congenital heart disease. A 3D electroanatomic mapping can visualize the abnormal myocardium and the anatomical barrier which construct the isthmus of the reentrant circuit of figure-8, single-loop, or double loop morphology. Catheter ablation can eliminate most of tachycardias if the critical isthmus is precisely located by anatomic and entrainment mapping during tachycardia. Detailed potential and pace mapping during sinus rhythm is also helpful in identifying the optimal ablation site or the isthmus, when activation mapping is not available because of hemodynamically unstable or nonsustained tachycardia.