Epidemiological features of infective endocarditis have changed during the last decades because of an increase in degenerative valvular disease in the elderly, placement of prosthetic valves, and exposure to invasive procedures. Although lower mortality rates have been observed over the last decades, overall mortality remains high.

This was a prospective study which included all patients diagnosed with infective endocarditis (IE) and hospitalized in the cardiology department of Monastir hospital between 1983 and 2017. We included patients who were diagnosed with definite infective endocarditis based on the modified Ducke criteria. And the aim was to analyse epidemiology, and predictors of 6-month mortality in infective endocarditis.

A prospective observational cohort study included 240 patients with definite IE. Thirty-two percent of episodes involved prosthetic valves. Thirty percent of episodes were nosocomial. Thirty-three percent included staphylococci, 22% streptococci, and 10% enterococci. At least one complication occurred in 59% of the episodes and 43% had surgical intervention. Six-month mortality was 20%: 29% for staphylococci, 19% for enterococci, and 9% for streptococci. Seventy-one percent of patients with a contraindication to surgery died when compared with 7% with medical treatment without a contraindication and 13% with surgical treatment. In multivariable logistic regression, predictors of 6-month mortality were age (P=0.04), the causative microorganism (P=0.03), and treatment group (P=0.03).

Compared with older series, we observed more prosthetic valve IE, nosocomial IE, and surgery. Staphylococcus aureus was the predominant microorganism. Age, staphylococci, and the contraindication to surgery were the main predictors of 6-month mortality.