Continuous wave Doppler assessment of patients subjected to pulmonary balloon valvoplasty.

To evaluate the role of Doppler ultrasound in accurately quantitating patients with valvar pulmonary stenosis, we studied 30 patients (20 patients undergoing balloon pulmonary valvoplasty before and after the procedure, and 10 patients who had previously undergone pulmonary balloon valvoplasty) by Doppler echocardiography and cardiac catheterization. The peak systolic gradient was calculated by the two methods within 24 hours of each other. The maximal velocity of blood flow was obtained by non-imaging, continuous wave Doppler ultrasound examination performed from various parasternal and subcostal positions and the valve gradient was calculated using a modified Bernoulli's equation. Transpulmonary peak systolic gradient calculated by Doppler examination ranged from 9 to 159 mm Hg (mean 54.8 +/- 34.5 mm Hg) and correlated well with values obtained at cardiac catheterization (r = 0.94, P less than 0.001). Thus our study shows that accurate quantification of pulmonary valve stenosis can be reliably undertaken non-invasively utilizing Doppler echocardiography.