Fig. 2

Left ventricular summit area ablation. (A) A modified right anterior oblique (RAO) view of a partial three-dimensional (3D) electro-anatomical mapping (EAM) activation map of the right atrium (RA), the coronary sinus (CS) and its continuation into the great cardiac vein (GCV) where the earliest local ventricular activation during left ventricular (LV) summit ventricular ectopy was found and successfully ablated (red dot). (B) Surface (I, III and V6) and intra-cardiac electrograms (ABLd and ABLp) revealing the earliest local ventricular activation (− 30 ms) during LV summit ectopy as recorded in the GCV. Before actual ablation at the earliest activation site selective left coronary angiography in a modified RAO view was performed as shown on (C, D). Red arrow on (C) points at the tip of the ablation catheter touching the proximal part of the LCX in which case the catheter was slightly withdrawn to the site marked with the white arrow on (D) showing the tip at the safe distance from the LCX at the location of the eventual successful ablation. His marks the His bundle location; SVC superior vena cava; IVC inferior vena cava