[Infective endocarditis: clinical echocardiography]

Abstract

Infective endocarditis is a rare but serious disease. The incidence in western countries is 1.7-6.2 cases/100,000 per year. The mortality rate today is 20-40%. The Duke University incorporates echocardiographic findings as one of the major criteria in the diagnosis of infective endocarditis. In case of suspected infective endocarditis, echocardiography is used to: 1) detect and characterize endocarditic vegetations; 2) detect complications; 3) conduct follow-up after treatment. Sensitivity for detection of vegetations in native-valve endocarditis is < 65% by transthoracic echocardiography, whereas it is 82-100% by transesophageal echocardiography; in infective endocarditis on prosthetic valves, sensitivity is 16-36 and 82-96%, respectively. Echocardiographic studies have demonstrated that highly mobile vegetations with a diameter of > 10 mm are more likely to cause complications (embolism, heart failure, need for surgery, and death). Another important advantage offered by echocardiography is the ability to accurately detect cardiac complications of infective endocarditis: valvular regurgitation, valve rupture, periannular abscess, prosthetic dehiscence, rupture of cardiac fibrosa, septal abscess, hemopericardium, and myocardial infarction. The sensitivity of transthoracic echocardiography for the detection of periannular abscess is 28% whereas that of transesophageal echocardiography is 87%. Finally, echocardiography has an invaluable role in indicating if surgery is required in cases of infective endocarditis with severe complications.