Although qualitative measures of AR severity are adequate in many situations, when AR is signifi- cant (Stages B and C), quantitative measures of regurgitant volume and effective regurgitant orifice (ERO) area1 are better predictors of clini- Measures of LV systolic function (LVEF or fractional shortening) and LV end-systolic dimension (LVESD) or LV end-systolic volume are predictive of the development of HF symptoms or death in initially asymptomatic patients (Stages B and C1) and are significant determinants of survival and functional results after surgery in asymptomatic and symptomatic patients (Stages Symptomatic patients (Stage D) with normal LVEF have a significantly better long- term postoperative survival rate than those with depressed systolic function. 2. Auscultation has high specificity for detecting AR but low sensitivity and diagnostic accuracy.27 TTE can identify AR in patients who have been deemed to be at risk on the basis of the presence of known aortic dilation or a condition associated with abnormal aortic valve function, such as a BAV. 3. TTE and CMR are useful for evaluating patients in whom there is discordance between clinical assessment and severity of AR by TTE or when TTE images are suboptimal. CMR imaging pro- vides accurate and reproducible measures of regurgitant volume and regurgitant fraction in patients with AR, as well as assessment of aortic morphology, LV volume, and LV systolic func- tion. Cardiac catheterization with LV and aortic angiography, as well as quantitation of regurgi- tation severity, is another option.20 25,28 30 4.3.2. Medical Therapy Recommendations for Medical Therapy of Chronic AR Referenced studies that support the recommendations are summarized in Online Data Supplement 14. 