Clinical characteristics, treatment, and outcomes in CIED-related versus left-sided infective endocarditis: a nationwide study from the NIDUS registry

Structured Abstract Background and Aims Cardiac implantable electronic device (CIED)-related infective endocarditis (IE) presents distinct diagnostic and therapeutic challenges due to its unique characteristics and limited evidence supporting guidelines compared with left-sided valvular IE. We aimed to examine clinical characteristics, treatment, and mortality in patients with CIED-related IE versus left-sided valvular IE. Methods We included patients with first-time IE using nationwide data from the NatIonal Danish endocarditis StUdieS (NIDUS) registry (2016-2021) and categorised them into isolated CIED-related IE without concomitant valvular IE and left-sided valvular IE. Results A total of 340 patients with isolated CIED-related IE and 2,510 patients with left-sided IE were included. Patients with CIED-related IE vs. left-sided IE were older (76.1 vs. 73.2 years), and a higher proportion were males (78.5% vs. 65.9%), had diabetes (32.9% vs. 21.9%), heart failure (46.2% vs. 11.7%), Staphylococcus aureus (37.1% vs. 30.7%), coagulase-negative staphylococci (11.2% vs. 6.4%), and culture-negative IE (12.1% vs. 7.8%). However, fever at admission was lower in CIED-related IE (55.4% vs. 61.5%). CIED removal was performed in 78.2% of patients with CIED-related IE. The six-month cumulative incidence of mortality was 20.4% (95% CI:16.2-24.9%) in CIED-related IE and 26.8% (95% CI:25.1-28.6%) in left-sided IE (P=0.009). In a multivariable Cox regression model, CIED-related IE was associated with lower six-month mortality compared with left-sided IE (adjusted HR:0.52 [95% CI:0.40–0.68], P<0.001). Conclusion In this nationwide study, patients with CIED-related IE were distinctly different from those with left-sided IE. Staphylococci were more prevalent, and despite higher age and differences in comorbidities, mortality was lower.