Risk factors of pericardial effusion in native valve infective endocarditis and its influence on outcome: A multicenter prospective cohort study

Abstract Background Pericardial effusion is a frequent finding in the setting of infective endocarditis. Limited data exists on clinical characteristics and outcomes in this group of patients. We aimed to determine the associated factors, clinical characteristics, and outcomes of patients who had pericardial effusion and native valve infective endocarditis. Methods and results A total of 1205 episodes of infective endocarditis from 25 Spanish centers between June 2007 and March 2013 within the Spanish Collaboration on Endocarditis (GAMES) registry were included. Echocardiogram at admission, clinical and microbiological variables, and one-year follow-up were analyzed. Pericardial effusion was observed in 7.8% (94/1205 episodes) of episodes of infective endocarditis, most of them being mild or moderate (93.6%). The presence of pericardial effusion was associated with a higher risk of heart failure during admission (OR 1.9; CI 95% 1.2–3.0). Patients with pericardial effusion had a higher rate of surgery (53.2% vs. 41.1%; p  = 0.02); however, this association was no longer significant after adjusting for possible confounders (OR 1.4; CI 95% 0.9–2.2; p  = 0.10). The presence of pericardial effusion was not associated with a higher in-hospital or one-year mortality (33.0% vs. 25.2%; p  = 0.10 and 40.2% vs. 37.3%; p  = 0.60 respectively). Conclusions The prevalence of pericardial effusion in patients with infective endocarditis was lower than previously reported. The presence of pericardial effusion is associated with the development of heart failure during hospitalization making it a warning sign, possibly reflecting indirectly a mechanical complication, which, however, if treated surgically in a timely manner does not change the final outcome of patients.