Practical Approaches to Catheter Ablation of Idiopathic Ventricular Arrhythmias

Abstract

In this review, we provide a practical approach to the catheter ablation of idiopathic focal ventricular arrhythmias (VAs) by summarizing the electrocardiographic (ECG) characteristics, mapping strategies, and ablation techniques for each of the major types of idiopathic VAs. We identify special considerations to be taken when treating specific forms of idiopathic VAs with catheter ablation that can increase success rates and reduce complications. Insights on ECG morphologies of VAs have led to novel criteria that can aid in accurate identification and localization of VA sites of origin. Advancements in mapping catheters and software as well as the use of intracardiac echocardiography have allowed for more precise mapping and ablation of arrhythmias arising from complex cardiac structures. Idiopathic VAs occurring in patients without overt structural heart disease can be categorized into four groups on the basis of anatomic location: (1) outflow tract VAs (which include the right ventricular outflow tract, left ventricular outflow tract, and left ventricular summit; (2) fascicular VAs; (3) papillary muscle VAs; and (4) annular VAs. Knowledge of the ECG characteristics of idiopathic VAs and the three-dimensional anatomy surrounding their sites of origin can guide pre-procedure planning, prioritization of cardiac regions for mapping, and approach for ablation.