Ventricular arrhythmias (VAs) account for the vast majority of the 250,000 cases of sudden death recorded in Europe each year. VAs occur mainly in patients with cardiomyopathy. Intra fibrotic electrical reentrant circuits are the dominant electrophysiological mechanism. Catheter ablation is the main option for invasive treatment, involving destruction of the slow conducting channels within the scar to block the electrical circuits. Challenges related to adequate catheter placement over the target area, sufficient energy diffusion into the tissue, and lack of intramyocardial dynamic mapping result in only 30-50% of patients experiencing freedom from recurrence after ablation. The aim of the CALAMAR (ChemicAL Ablation and Mapping of ARrhythmias) project is to evaluate the use of ultrasound to 1) Map the myocardium during ablation procedure using electromechanical wave imaging (EWI); 2) Validate a disruptive strategy of "chemical" ablation combining microbubbles and ultrasound to open the blood-myocardium barrier, and lipid nanoparticles loaded with cardiotoxic agents to induce a chemical dechannelization.