Infective endocarditis (IE) is a frequent and serious complication of implanted intracardiac prosthetic material, with a high morbidity and mortality. Therefore, this study aims to improve outcome of IE, with a focus on patients with intracardiac prosthetic material. In this study the investigators deal with research questions about both the diagnosis (microbiological, imaging, and expert opinion) and treatment of IE (with antimicrobial agents and surgical), in order to improve these clinical components and ultimately aim to improve outcome.