Clinical characteristics and risk factors for right-sided infective endocarditis in Korea: a 12-year retrospective cohort study

Right-sided infective endocarditis (RSIE) is less common than left-sided infective endocarditis (LSIE) and exhibits distinct epidemiological, clinical, and microbiological characteristics. Previous studies have focused primarily on RSIE in patients with intravenous drug use. We investigated the characteristics and risk factors for RSIE in an area where intravenous drug use is uncommon. A retrospective cohort study was conducted at a tertiary hospital in South Korea. Patients diagnosed with infective endocarditis between November 2005 and August 2017 were categorized into LSIE and RSIE groups. Of the 406 patients, 365 (89.9%) had LSIE and 41 (10.1%) had RSIE. The mortality rates were 31.7% in the RSIE group and 31.5% in the LSIE group (P=0.860). Patients with RSIE had a higher prevalence of infection with Staphylococcus aureus (29.3% vs. 13.7%, P=0.016), coagulase-negative staphylococci (17.1% vs. 6.0%, P=0.022), and gram-negative bacilli other than HACEK (12.2% vs. 2.2%, P=0.003). Younger age (adjusted odds ratio [aOR] 0.97, 95% confidence interval [CI] 0.95-0.99, P=0.006), implanted cardiac devices (aOR 37.75, 95% CI 11.63-141.64, P <= 0.001), and central venous catheterization (aOR 4.25, 95% CI 1.14-15.55, P=0.029) were independent risk factors for RSIE. Treatment strategies that consider the epidemiologic and microbiologic characteristics of RSIE are warranted.