Prognostic role of aetiological agent vs. clinical pattern in candidates to lead extraction for cardiac implantable electronic device infections

Cardiac implantable electronic devices infections (CIEDI) are associated with poor survival despite the improvement in transvenous lead extraction (TLE). Aetiology and systemic involvement are driving factors of clinical outcomes. The aim of this study was to explore their contribute on overall mortality. A prospective study was performed between 2011 and 2021, including all TLE candidates at our regional referral University hospital for CIEDI with microbiological confirmed aetiology. Considering significant predictors of mortality at multivariate Cox regression analyses, a 5-point BOP₂D score was developed, and it was validated with a prospective cohort from the Padua University. 157 patients were enrolled (mean age 71.3 ± 12.3 years, 81.5% male). S. aureus was isolated in 32.5% of patients, and it was more associated with valvular heart disease, systemic infection, and chronic kidney disease. CIEDI pattern was associated with 1-year mortality, with a significantly worse outcome in patients with "cold closed pocket" (CCP). The developed BOP₂D score presented a 0.807 AUC (95%CI 0.703-0.910, p < 0.001) and a good predictive value (OR 2.355, 95%CI 1.754-3.162; p < 0.001), and was associated with a progressive increase in mortality with a score > 2. The score validation with the registry from the Padua University (135 patients) retrieved a C-statistic of 0.746 (95%CI 0.613-0.879; p = 0.002). Both CCP and S. aureus were confirmed as risk factors for mortality in CIEDI patients. This study supports the hypothesis that the infectious process may occur through different mechanisms associated with different infection patterns, and high-risk patients should be considered for specific and aggressive approaches.