The long term prognosis of infective endocarditis

Three problems hamper the prognosis of patients who survive the initial phase of infective endocarditis (IE): the rate of IE recurrence is 0.3-2.5/100 patient years, about 60% of patients will have to be operated on at some time, 20-30% during the initial stay, 30-40% during the following 5-8 years; five-year survival after the hospital phase is about 75% in previous reports and 85% in more recent papers. Death is mainly due to heart failure. We looked at the long-term survival of 330 patients with IE who were hospitalized in our institution in 1970-1982, and at the potential influence of 10 factors: age, gender, previous heart disease, microorganism, location of IE, onset of IE, congestive heart failure (CHF) at onset, CHF during the first year, persistent fever, surgery at the acute phase. Global survival was 75% at 6 months, and 57% at 5 years. The only non-significant factor was IE location. The annual instantaneous risk of death was 0.55 at 6 months, 0.18 at 1 year, then 0.03. After one year, the only prognostic factor was age. The relative risk of dying among patients with IE who survived the first year, as compared to the risk of dying among the general population, was 3.27. The IE prognosis is not uniform. Mortality is high during the initial phase, but after one year the risk of dying is low, although still above that of the general population. Part of the risk is probably the direct consequence of IE, but part is due to the course of the underlying heart disease.