BACKGROUND Left ventricular (LV) systolic dysfunction and moderate aortic stenosis (AS) are more frequent with advancing age and often coexist. Afterload reduction is the mainstay of pharmacological treatment of heart failure (HF). Aortic valve replacement (AVR) is only formally indicated for symptomatic severe AS. OBJECTIVES This study sought to determine the clinical outcome of patients with concomitant moderate AS and LV systolic dysfunction. METHODS Echocardiographic and clinical data of patients with moderate AS and LV systolic dysfunction between 2010 and 2015 from 4 large academic institutions were retrospectively analyzed. Moderate AS was defined as aortic valve area between 1.0 and 1.5 cm(2) and LV systolic dysfunction defined as LV ejection fraction <50%. The primary endpoint was a composite of all-cause death, AVR, and HF hospitalization. RESULTS A total of 305 patients (mean age 73 +/- 11 years; 75% male) were included. The majority were symptomatic at the time of index echocardiogram (New York Heart Association [NYHA] functional class II: 42%; NYHA functional class III: 28%; and NYHA functional class IV: 4%). Ischemic heart disease was present in 72% of patients. At 4-year follow-up, the primary composite endpoint occurred in 61%. The main predictors for the primary endpoint were male sex (p = 0.022), NYHA functional class III or IV (p < 0.001), and peak aortic jet velocity (p < 0.001). The rate of the composite of all-cause death or HF hospitalization was 48%, rate of all-cause death was 36%, and rate of HF hospitalization was 27%. AVR occurred in 24% of patients. CONCLUSIONS Patients with concomitant moderate AS and LV systolic dysfunction are at high risk for clinical events. Further studies are needed to determine if earlier AVR in these patients might improve clinical outcome. (C) 2017 by the American College of Cardiology Foundation.