Abstract Background Surgery remains a pivotal treatment option for selected patients with left-sided infective endocarditis (IE). However, clinical equipoise exists for those with a European Society of Cardiology (ESC) guideline-indication for emboli prophylactic surgery. Purpose This study aimed to assess if surgical treatment combined with medical therapy in patients with definite left-sided IE with vegetations ≥10mm without heart failure or abscess was associated with a lower one-year rate of the composite outcome of relapse of bacteremia, new IE event, embolic event or all-cause mortality compared to medical therapy alone. Methods We used the National Danish Endocarditis Studies (NIDUS) registry (2016-2021) and identified all first-time definite IE cases with vegetation between 10-30mm. Patients were excluded if they met one of the following criteria: class I indication for surgery (per ESC 2015 guidelines on IE), age≥85 or age18 years, liver cirrhosis, severe chronic obstructive pulmonary disease, and hemorrhagic stroke before surgery. Surgery vs. medical therapy only was compared using survival statistics with Kaplan-Meier (unadjusted), time-dependent Cox regression models with time to surgery as the time-dependent variable, and then inverse probability of treatment weighting (IPTW) in a weighted Cox model. Results We identified 712 cases of definite left-sided IE with our inclusion criteria and no exclusion criteria, of whom 226 (31.7%) patients underwent valvular surgery. Patients who underwent surgery were younger (median age 65.9 vs. 74.1 years), had a higher proportion of men (76.1 vs. 67.5%), and had a lower comorbidity burden including diabetes, chronic kidney disease, and known heart failure compared to patients who received medical therapy only. Patients who underwent surgery had less frequent prosthetic valve endocarditis (11.9 vs. 22.6%) and larger vegetations (median of 15 vs. 12mm, p0.001) compared with patients who received medical therapy only. Streptococci were the most predominant bacteria among patients who underwent surgery (42.5 vs. 29.6%) compared to S. aureus in those who received medical therapy only (32.3 vs. 24.8%). The absolute rate of the composite outcome was lower for patients who underwent surgery compared to those who received medical therapy only (18.2 vs. 41.7%, p0.001, Figure 1). In the multivariable-adjusted Cox model, surgery was associated with a lower one-year rate of the composite outcome (HR 0.61 95% CI: 0.42–0.87). Similar findings were observed in the IPTW Cox model (HR 0.74 95% CI: 0.60–0.90). Conclusions Embolic-preventive surgery in patients with left-sided definite IE with a large vegetation ≥10mm was associated with better outcomes. However, selection bias is evident and randomized controlled trials are warranted to evaluate the clinical efficacy of embolic preventive surgery.Figure 1
Graversen et al. (Sat,) studied this question.