Mapping and Ablation of Ventricular Tachycardia in Nonischemic Left Ventricular Cardiomyopathy

Nonischemic cardiomyopathy incorporates a diverse group of structural heart disease, some of which are genetic in etiology, many of which involve intramural or epicardial substrate for ventricular arrhythmias. Substrate distribution varies according to etiology and has prognostic and procedural implications with regard to mapping and ablation. Multimodality imaging has played an important role in characterization of cardiomyopathy subtypes, as well as in guiding approach for ventricular tachycardia ablation in this challenging patient population. This review will summarize the available data on ventricular tachycardia mapping and ablation in patients with nonischemic left ventricular cardiomyopathy. Current understanding of nonischemic scar types, associated etiologies, as well as the value of multimodality imaging as an adjunctive, noninvasive mapping tool will be highlighted. Furthermore, adjunctive ablation techniques particularly for challenging substrate will be discussed.