Figure 4.

Electroanatomical substrate of Brugada syndrome. Examples of electroanatomical map abnormalities involving the right ventricle are shown in a patient with genetically proven BrS. The disproportion between low-voltage areas in bipolar (panel (A)) and unipolar (panel (B)) endocardial maps indicates the presence of a deep arrhythmogenic substrate consistent with classic arrhythmogenic right ventricular cardiomyopathy. The activation map during sinus rhythm (panel (C)) shows an extensive area of late potentials within the basal lateral segment of the right ventricle. In this patient, radiofrequency energy was extensively delivered (panel (D)), aimed at the complete abolishment of abnormal potentials in the right ventricle. No ventricular arrhythmias were induced on post-procedural programmed ventricular stimulation. BrS = Brugada syndrome.