Criteria for intervention Intervention is indicated when AR is severe and is causing symptoms AR is severe and is causing LV dysfunction (EF ≤ 55%, LV end-systolic dimension > 50 mm, or indexed to body surface area > 25 mm / m 2) AR is severe and at least 3 serial studies show a progressive decline in EF to 55 to 60%, or progressive increase in LV end-diastolic dimension to > 65 mm Patients with an enlarged ascending aorta frequently have AR as well as an increased risk of aortic dissection.