ECHONOMY Tools for Echocardiographic Calculations Muhamed Saric, MD, PhD New York University

Cardiac output (CO)

liters/minute

Mean pressure gradient (MPG):

mm Hg

Valve area = CO / sq root of MPG

Hakki A, Iskandrian A, Bemis C, Kimbiris D, Mintz G, Segal B, Brice C. A simplified valve formula for the calculation of stenotic cardiac valve areas. Circulation 1981;63(5):1050–5.