Challenges in cardiology: diagnosis of native and prosthetic valve endocarditis.

New cardiovascular imaging technologies have strongly influenced the diagnosis of bacterial endocarditis [infective endocarditis (IE)]. The clinical presentation of IE is polymorphic, which explains the difficulty of diagnosis and the delay in treatment. Symptoms such as fever, chills, loss of appetite and weight, and embolic phenomena strongly support the diagnosis of endocarditis, but are not always present, particularly in elderly or immuno-compromised patients. Moreover, subtle symptoms in patients at high risk for the development of IE, such as those with prosthetic valves or intracardiac devices, patients with congenital heart disease, and drug addicts should lead to the suspicion that a diagnosis of IE is highly probable. In this review, we will focus on the diagnosis of complex IE in native valves and prosthetic valves.