The management of ventricular arrhythmias by catheter ablation is a continually evolving field. A better understanding of arrhythmia mechanisms combined with the diverse range of technologies that have become available make this an exciting area of practice. The recently released EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias1 attempts to put the field into perspective. Experts brought their combined experience and the body of published knowledge together to present the current state of practice and recommendations for future directions. This article summarizes the contents of this excellent reference work.

Work of the Task Force

The consensus document provides an overview of ventricular arrhythmia mechanisms and rationale for ablation, indications for catheter ablation, technical aspects, the approach to treatment of ventricular tachycardia (VT) in structural heart disease, outcomes of ablation in specific disease states, and a summary of idiopathic ventricular tachycardias with approaches to treatment. In addition, training and institutional requirements and competencies are discussed, as well as clinical trial considerations.

The task force defined consensus as 70% or greater member agreement. The various topical areas follow.

Ventricular Tachycardia: Definitions, Mechanisms, and Rationale for Ablation

Standardization of terminology was the initial task of the group. This was felt to be important so that endpoints, methods, and outcomes would be spoken of in the same language across all treatment centers. A detailed definition list is found in the beginning of the document.

The mechanisms of various types of VT provide the rationale for potential cure by catheter ablation. Mechanisms of triggered activity and automaticity, scar-related reentry, and reentry within the Purkinje system are discussed in detail. The approach for idiopathic VT should involve mapping to find a focal origin or a key point on a reentry path. In the case of scar-related VTs, the critical isthmus should be identified and transected. For those with unmappable VTs, larger areas are targeted. With Purkinje reentry, conduction fibers that participate in the circuit are sought and ablated.

Indications for VT Ablation

Advances in ablation technology and mapping techniques have led to the ablation option for VT being considered much earlier in the treatment course. The consensus group recommendations for VT ablation indications are seen in Tables 1, 2, and 3.

Technical Aspects

The group recognized the limitations of recommending various newer technologies due to the lack of controlled studies and head-to-head comparisons in the published literature. In addition, the added cost of newer technologies was mentioned. The improved outcomes seen with use of some technologies, however, was considered a positive aspect. It is the hope of the consensus members that clinical trials will be conducted to assess further technological developments.

The contribution of newer mapping systems was discussed, both electroanatomic systems and multielectrode arrays. The ability to create chamber geometry and voltage maps has increased success rates and decreased procedure time.