Comparison of Outcomes of Atrial Fibrillation in Patients With Reduced Versus Preserved Left Ventricular Ejection Fraction

Patients with newly diagnosed atrial fibrillation (AF) and a rapid ventricular response may present with a reduced left ventricular ejection fraction (LVEF). We compared long-term outcomes of these patients with those with preserved LVEF. This retrospective cohort study included 385 consecutive adults with newly diagnosed AF with rapid ventricular response, presenting to a single medical center from January 2006 to August 2014. Patients with a history of coronary artery disease or known cardiomyopathy were excluded. Patients were divided into 2 groups: those with an LVEF ≤55% (n = 147) (REF) and those with an LVEF >55% (n = 238) (PEF). Echocardiographic parameters, all-cause mortality, cardiovascular mortality, and stroke rates were compared between both groups at baseline and a minimum of 1-year follow-up. The mean age of patients was 68 ± 1.1 in REF versus 60 ± 7.4 in PEF (p = 0.39). There were no significant differences in baseline co-morbidities between both groups. The mean LVEF during the index admission was 47.7 ± 0.8% in REF versus 65.5 ± 0.3% in PEF. The average duration of follow-up was 2.8 years. Patients with REF had higher all-cause mortality (32.7% REF vs 20.6% PEF, odds ratio 2.17, p = 0.008). Patients with REF had higher rates of subsequent clinic or ER visits for AF with a rapid ventricular response (32% REF vs 22.7% PEF, p = 0.044). The incidence of stroke was similar between both groups (17% REF vs 18.9% PEF, p = 0.639). Of the patients with REF, 64% had subsequent EF recovery and had similar outcomes compared with patients with PEF. Baseline LV end-diastolic diameter predicted all-cause mortality (odds ratio 1.14, p = 0.003) in the REF group. None of the echocardiographic parameters predicted EF recovery. In conclusion, in patients with new AF with rapid ventricular response, REF was associated with higher long-term all-cause mortality. Those with subsequent LVEF recovery after medical therapy appear to have a similar prognosis compared with those with initial PEF.