Background-Aortic valve replacement (AVR) in patients with severe aortic regurgitation (AR) and left ventricular (LV) dysfunction entails a higher surgical risk. Though it may improve symptoms and LV size, it is not known whether it translates into a survival benefit. Methods and Results-This retrospective cohort study included patients screened from our echocardiographic database between 1993 and 2007 for patients with severe AR and LV ejection fraction (EF) <= 35%. Charts reviews were conducted for clinical, pharmacological, and surgical information. Mortality data were obtained from the social security death index and analyzed as a function of AVR adjusted for the propensity score. Of the 785 patients with severe AR, 166 patients had severe LV dysfunction defined as an EF <= 35%: 69% of these were men, age 65 +/- 16 years, and LV EF was 23 +/- 8%. Kaplan-Meier analysis revealed that performance of AVR (n=53) was associated with a better survival (P=0.001). Adjusted for the propensity score, AVR was associated with a significantly lower mortality hazard (HR 0.59, CI 0.42 to 0.98, P=0.04). Conclusions-There is a clear reluctance to offer AVR in a large number of patients with severe AR associated with LV dysfunction. However, the performance of AVR in these patients is associated with a mortality benefit supporting the current ACC/AHA guidelines. (Circulation. 2009; 120[suppl 1]: S134-S138.)