Factors associated with local invasion in infective endocarditis: a nested case-control study.

OBJECTIVE

A substantial proportion of infective endocarditis (IE) cases are complicated by local invasion. The purpose of this study was to identify patient and disease characteristics associated with local invasion in surgically treated IE patients.

METHODS

This was a nested case-control study. All episodes of IE for patients admitted to Cleveland Clinic from 1 January 2013 to 30 June 2016 were identified from the Cleveland Clinic IE Registry. Patients ≥18 years of age who underwent surgery for IE were included. Among these, cases were those with local invasion, controls were those without. Local invasion, defined as periannular extension, paravalvular abscess, intracardiac fistula or pseudoaneurysm, was ascertained from the surgical operative note. Associations of selected factors with local invasion were examined in a multivariable logistic regression model.

RESULTS

Among 511 patients who met inclusion criteria, 215 had local invasion. Mean age was 56 years; 369 were male. Overall 345 (68%) had aortic valve, 228 (45%) mitral valve, and 66 (13%) tricuspid or pulmonic valve involvement. Aortic valve involvement (OR 6.23, 95% CI 3.55-11.44), bioprosthetic valve (OR 3.88, 95% CI 2.36-6.44), significant paravalvular leak (OR 3.80, 95% CI 1.60-9.89), new atrioventricular nodal block (OR 3.77, 95% CI 1.87-7.90), infection with streptococci other than viridans group streptococci (OR 7.54, 95% CI 2.42-24.87) and presence of central nervous system emboli (OR 1.85, 95% CI 1.13-3.04) were associated with local invasion.

DISCUSSION: Intracardiac and microorganism factors, but not comorbid conditions, are associated with local invasion in IE.