Atrial fibrillation in endomyocardial fibrosis is a marker of worse prognosis.

We studied the incidence of AF in patients with endomyocardial fibrosis (EMF) and its influence on prognosis and associated clinical events. One hundred and sixty consecutive patients with EMF were followed for a mean period of 4 years. Their mean age was 39.7 years. There were 114 women. During follow-up there were 56 deaths. Eighty-eight patients (55%) were submitted to surgical intervention. AF was observed in 58 cases (36.2%). The presence of AF was associated with a greater prevalence of dyspnea, peripheral edema, hepatomegaly, lower left ventricular ejection fraction, lower right ventricular systolic pressure (37.8 vs 45.6 mmHg, P=0.0392), and greater incidence of tricuspid regurgitation (86.0 vs 63.2%, P=0.004). AF was more frequent among patients in whom the disease involved the right ventricle, particularly those with intense fibrosis. Overall, patients with AF had a higher mortality rate than those who did not have AF (43.1 vs 30.3%, P=0.0195), but among those submitted to surgery, AF did not have an impact on survival. In conclusion, AF is frequent among patients with EMF. It is more prevalent among patients with right ventricular involvement and its presence is associated with a greater incidence of heart failure. AF is associated with worse prognosis, but surgery potentially reverses this bad evolution.