Algorithm for the management of aortic stenosis (AS). See Fig. 256-4, in HPIM-20 for explanation of specific stages A-D of disease progression. AS, aortic stenosis; AVA; aortic valve area; AVR, aortic valve replacement by either surgical or transcatheter approach; DSE, dobutamine stress echocardiography; ETT, exercise treadmill test; LVEF, left ventricular ejection fraction; ΔP_mean, mean pressure gradient; and V_max, maximum velocity. (Adapted from Nishimura RA et al: 2014 AHA/ACC Guideline for the Management of Patients with Valvular Heart Disease. J Am Coll Cardiol 63:e57, 2014.)