Predictors of in-hospital mortality in infectious endocarditis

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Infectious endocarditis has a high rate of in-hospital complications and mortality, ranging between 15 and 30%. Still, there is a paucity of studies on the assessment of short-term prognosis in these patients. Purpose To determine predictors of in-hospital mortality in patients with infective endocarditis. Methods This was a retrospective study that included all patients hospitalized in a single centre with the diagnosis of infective endocarditis, between 2000 and 2020. The relationship between clinical, laboratory and echocardiographic variables and in-hospital mortality was evaluated. Results A total of 161 patients were selected, 65.8% were males, with a mean age of 66.4±16.4 years. The in-hospital mortality rate was 16.8%, occurring on average after 35.0±17.5 days of hospitalization. The average length of stay was 44.5±22.8 days. Age >70 years was associated with higher mortality rate (p=0.021). There were no other significant differences between groups regarding clinical variables and comorbidities. Although not statistically significant, in-hospital mortality group had higher mean ejection fraction (57.2±2.7% vs. 54.6±12.9%). Laboratory parameters associated with mortality included isolation of Staphylococcus (p=0.019) or Enterococcus (p=0.045) in blood cultures. Though the classification of endocarditis (in native vs. prosthesis valve) did not differ between groups, the presence of perivalvular complications on echocardiography (p= 0.042) namely pseudoaneurysm (p=0.003), were more frequent in the group with higher mortality rate. There were 70 patients with indication for urgent surgery, namely for locally uncontrolled infection in 29.2%, heart failure (20.0%) and prevention of embolic events (18.1%). The existence of urgent surgical indication (p=0.009) was associated with higher mortality, and surgery during hospitalization was associated with lower mortality (p=0.011). In a multivariate regression analysis, after adjusting for all the possible confounders, the independent predictors of in-hospital mortality were the previous history of heart failure (HR = 3.29, 95%CI 1.41-7.66), chronic liver disease (HR = 4.33, 95%CI 1.23-15.30) and evolution with septic shock (HR = 6.87, 95%CI 2.89-16.39). Conclusions The present study confirms the high mortality rate of patients with infective endocarditis, highlighting the importance of patient baseline characteristics and comorbidities, as it identified as independent predictors of in-hospital mortality the previous history of heart failure, chronic liver disease and evolution with septic shock.