Usefulness of New-Onset Atrial Fibrillation, as a Strong Predictor of Heart Failure and Death in Patients With Native Left-Sided Infective Endocarditis

Abstract

Atrial fibrillation (AF) is the most common cardiac arrhythmia in adults and has been independently related to increased morbidity and mortality. AF is a frequent arrhythmia in infective endocarditis (IE). Nevertheless, there are no data on how AF affects the clinical outcome of patients with endocarditis. Our purpose was to investigate patient characteristics, microbiology, echocardiographic findings, in-hospital course, and prognosis of patients with IE who develop new-onset AF (NAF) and compare them with those who remained in sinus rhythm (SR) or had previous AF (PAF). From 1997 to 2014, 507 consecutive patients with native left-sided IE were prospectively recruited at 3 tertiary care centers. We distinguished 3 groups according to the type of baseline heart rhythm during hospitalization and previous history of AF: NAF group (n = 52), patients with no previous history of AF and who were diagnosed as having NAF during hospitalization; SR group (n = 380), patients who remained in SR; and PAF group (n = 75), patients with PAF. Patients with NAF were older than those who remained in SR (68.3 vs 59.6 years, p <0.001). At admission, heart failure was more common in NAF group (53% vs 34.3%, p <0.001), whereas stroke (p = 0.427) was equally frequent in all groups. During hospitalization, embolic events occurred similarly (p = 0.411). In the multivariate analysis, NAF was independently associated with heart failure (odds ratio 3.56, p <0.01) and mortality (odds ratio 1.91, p = 0.04). In conclusion, the occurrence of NAF in patients with IE was strongly associated with heart failure and higher in-hospital mortality independently from other relevant clinical variables.