Prognostic implications of a negative echocardiography in patients with infective endocarditis

Echocardiography plays an important role in infective endocarditis (IE) diagnosis according with the modified Duke criteria. We evaluated the implications of a positive echocardiography in the prognosis of a cohort of patients with IE.

Prospective multicentre study in 31 Spanish centres. From January 2008 to September 2016, 3467 patients were included (2765 definite IE, 702 possible IE). The main outcome was in-hospital mortality. Echocardiography diagnosis was based on modified Duke criteria for the diagnosis of IE.

Median age was 69 years (interquartile range: 57-77 years). Comorbidity was high (mean Charlson index 4.7 ± 2.8). Transoesophageal echocardiography was performed in 2680 (77.3%). The overall inhospital mortality rate was 26.7%. Univariate analysis showed that, in patients with definite IE, inhospital mortality was similar in patients with positive and negative echocardiography (27.7% vs. 24.6%, respectively, p = 0.121). In possible IE these figures were 27.5% vs. 16.7%, respectively, p < 0.001. Complications (cardiac and extracardiac [embolic, immunological, and septic shock]) were more frequent with positive than with negative echocardiography, regardless of clinical suspicion (definite IE 35.5% vs. 16.8%, respectively, p < 0.001; possible IE 20.8% vs. 7.6%, respectively, p < 0.001). Positive echocardiography was a predictor of inhospital death by logistic regression modelling, after adjusting for confounders, definite IE (odds ratio [OR] 1.3, 95% confidence interval [CI] 1.02-1.76, p = 0.036), possible IE (OR 1.59, 95% CI 1.02-2.45, p = 0.036).

A positive echocardiography in patients with IE is associated with increased inhospital mortality, in addition to other clinical factors and comorbidities.