This is the first of a three-volume project aimed at providing unique case reports (20 cases per volume) of a large number of supraventricular and ventricular arrhythmias encountered in clinical practice. The book is focused on the treatment of supraventricular arrhythmias, namely focal atrial tachycardias, typical and atypical AVNRT and accessory pathways (both manifest and concealed). All presented-cases were performed using the CARTO electro-anatomical mapping system, which allows the reader to better understand the arrhythmia features due to the high number of images provided. A large number of high-quality figures, which represent the core of the authors  work, enrich the contents: all cases are built around suggestive figures acquired during the patients  hospitalization, which clearly illustrate important concepts used in catheter ablation of cardiac arrhythmias.