The term infective endocarditis (IE) refers to an infection of the endocardial surface of the heart, affecting the cardiac valves, mural endocardium, and septal defects. In most cases, the infection is caused by bacteria, but a fungal etiology is also possible. It is a life-threatening condition that despite antibiotic treatment, can rapidly develop into a hemodynamic collapse. IE often leads to damage of the heart valves and their subvalvar apparatus, resulting in uncontrollable regurgitation.
Risk factors for infective endocarditis include structural heart disease (repaired or unrepaired) and the presence of foreign material such as prosthetic valves, conduits, homografts, pacemaker leads, interventional devices, or central venous lines. IE is often induced by transient bacteremia caused, for example, by dental procedures or intravenous drug abuse.
The echocardiographic diagnosis is based on the detection of vegetations or abscesses. In patients with prosthetic valves, IE may manifest as valvar dehiscence or malfunction. In many cases, there are no compelling echocardiographic features despite repeatedly positive blood cultures in at-risk patients.
