After mastering epicardial revascularisation, the therapeutic management of acute coronary syndrome has progressively turned towards the preservation of the capillary microcirculation. In this respect, contrast echocardiography provides all the answers to the main questions which arise, and is available within a timeframe and place compatible with the management of such patients. The techniques for microbubble detection, quantification tools, and contrast agents are well optimised for routine use both for initial diagnosis as well as monitoring the therapeutic effectiveness. It is only the administrative authorisation which is currently lacking treatment.