Trend in Infective Endocarditis in Bulgaria: Characteristics and Outcome, 17-Years, Single Center Experience

Background: Infective endocarditis (IE) remains a difficult disease to diagnose and treat, with a persistently high mortality rate. There is a lack of recent data on IE in Bulgaria over the last decades. Methods: This study is retrospective, single-centered, and includes 270 patients diagnosed with IE for the period 2005-2021. We compared two periods, 2005-2015 (n = 119) and 2016-2021 (n = 151), to find the characteristics changes. Results: The study included 177 (65.5%) male patients. In the second period, there is a significant increase in age from 62 (44-73) to 67 (53-75), (p = 0.023); in the Charlson comorbidities index (CCI) from 3 (1-4) to 4 (2-6), (p = 0.000); in cases with chronic kidney diseases (CKDs) from 15 (12.6%) to 55 (36.9%), (p = 0.001); coronary arterial diseases (CADs) from 20 (16.85%) to 44 (29.1%), (p = 0.018); and atrial fibrillation (AF) from 13 (10.9%) to 36 (23.8%), (p = 0.006). Ejection fraction decreased significantly in the second period from 63 (56-70) to 59 (51-66), (p = 0.000). Almost half of the patients 123 (45.6%) had no known predisposing cardiac condition, and 125 (46.3%) had an unknown port of entry. IE was community-acquired in 174 (64.4%), healthcare-associated in 72 (26.7%), and injection-drug-use-related IE in 24 (8.9%). The study population included 183 (67.8%) native valve IE, 85 (31.5%) prosthetic IE, and 2 (0.74%) intracardiac-device-related IE. The hemocultures were positive in 159 (59.6%), and the most frequent pathogenic agent was staphylococci-89 (33.3%) (Staphylococcus aureus-44 (16.5%) and coagulase negative staphylococci-45 (16.8%)). Only 54 (20%) of patients underwent early surgery. The all-cause 30-day mortality rate was 67 (24.8%). There is no significant difference between the two periods in terms of the characteristics listed above. Conclusions: The profile of IE in Bulgaria has changed with increasing age and comorbidity, changing predisposing cardiac conditions, and entry door. The most common pathogen was the Staphylococcus spp. The 30-day mortality rate remains high.