Infective endocarditis at a tertiary care hospital in South Korea

Abstract

Objective: The treatment of infective endocarditis (IE) has become more complex with the current myriad healthcare-associated factors and the regional differences in causative organisms. We aimed to investigate the overall trends, microbiological features, and outcomes of IE in South Korea.

Methods: A 12-year retrospective cohort study was performed. Poisson regression was used to estimate the time trends of IE incidence and mortality rate. Risk factors for in-hospital mortality were identified with multivariable logistic regression, and model comparison was performed to evaluate the predictive performance of notable risk factors. Kaplan-Meier survival analysis and Cox regression were performed to assess long-term prognosis.

Results: We included 419 patients with IE, the incidence of which showed an increasing trend (relative risk 1.06, p=0.005), whereas mortality demonstrated a decreasing trend (incidence rate ratio 0.93, p=0.020). The in-hospital mortality rate was 14.6%. On multivariable logistic regression analysis, aortic valve endocarditis (OR 3.18, p=0.001), IE caused by Staphylococcus aureus (OR 2.32, p=0.026), neurological complications (OR 1.98, p=0.031), high Sequential Organ Failure Assessment score (OR 1.22, p=0.023) and high Charlson Comorbidity Index (OR 1.11, p=0.019) were predictors of in-hospital mortality. Surgical intervention for IE was a protective factor against in-hospital mortality (OR 0.25, p<0.001) and was associated with improved long-term prognosis compared with medical treatment only (p<0.001).

Conclusions: The incidence of IE is increasing in South Korea. Although the mortality rate has slightly decreased, it remains high. Surgery has a protective effect with respect to both in-hospital mortality and long-term prognosis in patients with IE.

Keywords: endocarditis; valve disease surgery.

Figure 1

Flow of patients suspected of having infective endocarditis during the study period.

Figure 2

Trends in the incidence and mortality rate of infective endocarditis according to calendar year in Poisson log-linear regression. Trends are depicted as green dashed lines.

Figure 3

Distribution of microorganisms causing infective endocarditis according to calendar year. CNS, coagulase-negative staphylococci; GNB, Gram-negative bacillus; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible Staphylococcus aureus.

Figure 4

Kaplan-Meier curves of the long-term survival rates of patients with infective endocarditis who underwent surgery versus those who underwent medical treatment only.