Impact of Microbiological Organism Type on Surgically Managed Endocarditis.

Document Type


Publication Date


Publication Title

The Annals of thoracic surgery


BACKGROUND: This study is the first to describe the impact of organism and valve type on surgically managed infective endocarditis (IE) from the Society of Thoracic Surgeons (STS) database. Previous risk models for surgically managed endocarditis have not included microbiological organism.

METHODS: The STS database was queried for adult patients with surgically managed endocarditis from 7/1/11-6/30/16. Outcomes were compared based on (1) causative microbiological organism, (2) valve type (native vs. prosthetic), and (3) right- (tricuspid) versus left- (mitral, aortic) sided endocarditis. Univariate and risk adjusted models were developed with odds ratios for mortality for each organism type referenced against streptococcus.

RESULTS: The study population included 21388 (93%) operations for left-sided and 1698 (7%) for right-sided IE. Streptococcus (28%) and staphylococcus (27%) were the most common infecting organisms, followed by enterococcus (11%). After multivariate adjustment, microbiological organism type was significantly associated with operative mortality for patients with left-sided endocarditis: adjusted odds ratio 2.9 for fungal, 1.4 for staph, and 1.3 for culture negative versus streptococcus. For right-sided endocarditis, there were no differences in outcomes by organism type. Left-sided prosthetic valve endocarditis had a higher operative mortality than left-sided native valve endocarditis (12% vs. 8%; p

CONCLUSIONS: Organism type influences the operative mortality for left-sided endocarditis. Surgery for left-sided and prosthetic valve endocarditis is associated with higher operative mortality. Risk adjustment for operative outcomes in endocarditis may need to account for microbiological organism type.

Clinical Institute

Cardiovascular (Heart)