Outpatient Echocardiographic Assessment of Complex Pulmonary Outflow Stenosis: Doppler Mean Gradient Is Superior to the Maximum Instantaneous Gradient

Evaluation of pulmonary outflow obstruction has focused on maximum instantaneous gradient (MIG). However, experience suggests that outpatient Doppler MIG often overstates the degree of stenosis. In this study of 132 patients with complex pulmonary stenosis, the mean Doppler gradient showed superior correlation and agreement with invasive peak-to-peak gradient (PPG) (r = 0.91, bias = -6 mm Hg). Agreement between mean gradient and PPG remained...