echocardiography: systolic flow velocity of left ventricular outflow tract with Valsalva
echocardiography: systolic flow velocity of left ventricular outflow tract with valsalva
echocardiography: systolic flow velocity of left ventricular outflow tract with Valsalva (procedure)
echocardiography: systolic flow velocity of left ventricular outflow tract with valsalva (procedure)