ROLE OF ECHOCARDIOGRAPHY IN EVALUATION OF PATIENTS WITH STAPHYLOCOCCUS-AUREUS BACTEREMIA - EXPERIENCE IN 103 PATIENTS

Objectives. The purpose of this prospective study was to examine the r ole of echocardiography in patients with Staphylococcus aureus bactere mia (SAB). Background. The reported incidence of infective endocarditi s (IE) among patients with SAB varies widely. Distinguishing patients with uncomplicated bacteremia from those with IE is therapeutically an d prognostically important, but often difficult. Methods. One hundred- three consecutive patients undergoing both transthoracic (TTE) echocar diography and transesophageal (TEE) echocardiography were prospectivel y evaluated. All patients presented with fever and greater than or equ al to 1 positive blood culture and were followed up for 12 weeks. Resu lts. Although predisposing heart disease was present in 42 patients (4 1%), clinical evidence of infective endocarditis (IE) was rare (7%). T TE revealed anatomic abnormalities in 33 patients, but vegetations in only 7 (7%), and was considered indeterminate in 19 (18%). TEE identif ied vegetations in 22 patients (aortic valve in 5, mitral valve in 9, tricuspid valve in 4, catheter in 2 and pacemaker in 2, abscesses in 2 , valve perforation in 1 and new severe regurgitation in 1; 26 total [ 25%]). Using Duke criteria for the diagnosis of IE, definite IE was pr esent in 26 patients (25%). Clinical findings and predisposing heart d isease did not distinguish between patients with and without IE. The s ensitivity of TTE for detecting IE was 32%, and the specificity was 10 0%. The addition of TEE increased the sensitivity to 100%, but resulte d in one false positive result (specificity 99%). TEE detected evidenc e of IE in 19% of patients with a negative TTE and 21% of patients wit h an indeterminate TTE. At follow up, cure of staphylococcal infection occurred in a similar percentage of patients with and without IE (77% and 75%, respectively). However, death due to sepsis was significantl y more likely among patients with IE (4 of 26 [15%]) than among those without IE (2 of 77 [3%]) (p = 0.03). Conclusions. Our results suggest that IE is common among patients admitted to the hospital with SAB an d is associated with an increased risk of death due to sepsis. TEE is essential to establish the diagnosis and to detect associated complica tions. Therefore, the test should be considered Dart of the early eval uation of patients with SAB. (C) 1997 by the American College of Cardi ology.