Eustachian valve endocarditis in the context of right atrial embryonic remnants: A systematic review and meta-analysis.

Background: Eustachian valve endocarditis (EVE) is a rare right-sided infective endocarditis (RSIE) manifestation. This condition has scattered and limited clinical characteristics that require collection and systematization. This meta-analysis evaluates the predisposing factors, pathogens, and associated risk profiles in EVE cases.

Methods: The meta-analysis included 68 cases of EVE from 57 reports published between 1986 and 2024 from PubMed, Embase, Scopus, Cochrane, and Web of Science. Data on demographics, clinical characteristics, risk factors, and microbiological findings were extracted and analyzed using descriptive and univariate statistical methods. Pooled prevalence rates from observational studies were calculated using a fixed effects model.

Results: The pooled prevalence of EVE in RSIE among the analyzed cases was 2.54%. Single-valve infections accounted for 70.6% of cases, with the Eustachian valve as the sole affected structure. The most common pathogen was Staphylococcus aureus (60%), predominantly affecting younger intravenous drug users (IVDU) with an odds ratio [OR (odds ratio), 6.27; 95% CI (confidence interval), 1.62-24.31] in univariate logistic regression analysis. Other predisposing factors, including central venous catheters (CVCs) and cardiac implantable electronic devices (CIED), were not significantly associated with Staphylococcus aureus or other bacterial non-Staphylococcus aureus or fungal infections.

Conclusions: EVE is relatively rare and primarily associated with IVDU and younger age, whereas CVCs and CIEDs are insignificant predictors. Identifying embryonic remnants like the Eustachian valve or Chiari network using echocardiography may facilitate early diagnosis in at-risk populations.