Temporary trends of cardiac device related infective endocarditis in a tertiary referral center between 2006 and 2022

FUNDING ACKNOWLEDGEMENTS: Type of funding sources: None. BACKGROUND: Infective endocarditis (IE) is a rare, but life-threatening complication of cardiac device implantation. Despite recent preventive strategies and advances in antimicrobial and surgical treatment, morbidity and mortality rates are still high. AIMS: The objective of our study was to assess the epidemiological characteristics, temporal trends and mortality rates of cardiac device related IE (CDRIE) in our high-volume, tertiary referral center. METHODS: retrospective data collection was performed between January 1, 2006 and March 31, 2022. Median follow-up was 3.8 yrs (IQR: 0.6 – 9.2 yrs). Patients admitted between 2006 and 2013 (group 1) and between 2014 and 2022 (group 2) were compared to assess temporal trends. Thirty-day, 6-month and 1-year mortality rates were estimated. RESULTS: During the observed 17 years 82 patients were admitted with CDRIE (61 males [74%]), mean age: 57.3 ±18 yrs; 6 VVI, 7 VDD, 17 VVI-ICD, 24 DDD, 10 DDD-ICD and 18 CRT devices [4 CRT-P, 14 CRT-D]); median time since first implantation was 3.8 yrs [IQR: 1.1 – 6.6 yrs]). Staphylococci were the most prevalent infective agents (62%), S. aureus (SA) infection was found in 37 cases (out of whom 13 were MRSA [16%]), coagulase negative Staphylococcus in 14 cases (17%), Enterococcus faecalis in 9 cases (11%), streptococci in 4 cases (5%), blood culture was negative in 13 cases (15%), and in 5 cases other pathogens were the underlying microorganism. Patients in Group 1 (n=42) did not differ from patients in Group 2 (n=40) in terms of age, male gender or ejection fraction. Patients in Group 2 had higher CRP level at admission (42,9 [IQR:34-55] mmol/l vs 90 [IQR:25-60] mmol/l, p=0.02). ICD lead (29% vs 67%, p<0.001) and E. faecalis infection (2% vs 20%, p=0.03) and percutan extraction (55% vs 75%, p=0.05) were more prevalent in Group 2. The 30-day and 6-month mortality rates were worse in Group 2 than in Group 1 (2% vs 17.5% p=0.03; and 16% vs 35% p=0.04 resp.) while the 1-year mortality did not differ (24% vs 40%). The all-cause mortality was 10% at 30 days, 26% at 6 month and 32% at 1 year. Univariate regression showed that age (HR: 1.03 [1.01-1.07] p<0.05), ejection fraction (HR: 0.96 [0.93-0.98] p<0.005), ICD lead (HR: 4.89 [1.82-14.40] p<0.005) and the time since first implantation (HR: 0.88 [0.77-0.98] p<0.05) were the predictors of 1-year mortality. However, in Cox multiple regression model only age (HR: 1.05 [1.004-1.1] p<0.05) and ICD lead (HR: 1.16 [1.16-17.38] p<0.05) remains independent predictors of outcome at 1 year. CONCLUSIONS: In the past 17 years the most prevalent underlying microorganism were staphylococcal species, although Enterococcus faecalis infection increased over time. Patients with CDRIE had poor prognosis, every third patient died at 1 year after diagnosis. The short-term prognosis is even worse in the past few years than before, which may be a negative consequence of limited accessibility of healthcare due to COVID 19 pandemic.