Reliability and accuracy of measurement of transductal gradient by Doppler ultrasound.

Simultaneous continuous wave Doppler echocardiography, aortic and pulmonary artery pressure measurements were performed during cardiac catheterization in 46 patients with patent ductus arteriosus. Doppler-derived systolic, mean and diastolic transductal gradients correlated well with those measured by catheterization, respectively (r = 0.972, SEE = 6.8 mmHg; r = 0.965, SEE = 5.4 mmHg; r = 0.939, SEE = 6.2 mmHg), and there were clinically acceptable agreements between the two technical measurements. It is concluded that Doppler echocardiography is a reliable and accurate technique for noninvasive estimation of transductal gradients.