[Usefulness of echocardiography in the diagnosis of infectious endocarditis]

Thirty-four patients with clinical diagnosis of infective endocarditis were studied with M mode and/or two-dimensional echocardiography. of them. Twenty-two were men; their ages ranged from 9 to 67 years. In 23 cases surgical or post mortem confirmation of the echocardiographic diagnosis was obtained. The clinical features as well as history of previous cardiopathy (94.1%) and its type (congenital 38.2%, rheumatic 29.4%, rheumatic with valvular prosthesis 23.5%) were analyzed. In the 23 patients with proven endocarditis, the echocardiographic diagnosis was positive in 19 (82%); vegetations were evident in 13. In 6 patients vegetations were not found. There were 3 false positive cases and one false negative, giving a sensitivity of 0.81 and a specificity of 0.85. The causes of false negative and false positive findings were analyzed. These were closely related to the duration of the disease and time which elapsed between the echocardiographic study and confirmation in surgery or necropsy as well as the size of the vegetations. The echocardiographic diagnosis was difficult when a valvular prosthesis was present. Echocardiography is a useful technique for diagnosis and follow up of patients with infective endocarditis.