Atrial voltage mapping: tailoring ablation approach by targeting the arrhythmogenic substrate
Acibadem City Clinic Tokuda Hospital, Sofia, Bulgaria
The interplay between triggers, arrhythmogenic substrate and modulators determines the pathophysiological and clinical course of atrial fibrillation. Catheter ablation is currently the mainstay of therapy of this complex arrhythmia. Although mainly based on pulmonary vein isolation empirical ablation approaches targeting extrapulmonary substrate have also been introduced. These include creation of linear lesions, extensive ablation of LA posterior wall, targeting fractionated electrograms, rotors maintaining AF, etc. However, many of these approaches are just empirical and do not provide an individualised approach to each patient. Recently, the concept of fibrotic atrial cardiomyopathy has been introduced to explain the occurrence and clinical course of many conditions including AF. Atrial voltage mapping is increasingly recognised as a means to identify those fibrotic areas. Targeting low voltage zones in the atria during catheter ablation of AF seems to be associated with better clinical outcomes. This review focuses on the association between low-voltage zones and atrial fibrosis. It covers many of the technical details and limitations of voltage mapping to identify atrial substrate. It also summarises the available data from clinical trials examining the role of voltage-driven ablation on procedural outcome on AF patients.