[Pulmonary arterial end-diastolic pressure noninvasively estimated by continuous wave Doppler echocardiography]

To estimate pulmonary arterial end-diastolic pressures noninvasively, we measured the pulmonary regurgitant flow velocity by continuous wave Doppler echocardiography in 17 patients with pulmonary hypertension (pulmonary arterial end diastolic pressure greater than or equal to 18 mmHg) and in 23 patients without pulmonary hypertension. Pulmonary regurgitation was successfully detected by continuous wave Doppler echocardiography in 14 of the 17 patients with pulmonary hypertension and in 14 of the 23 patients without pulmonary hypertension. The end-diastolic pulmonary artery-to-right ventricular pressure gradient was estimated from the Doppler-determined pulmonary regurgitant flow velocity by means of a simplified Bernoulli equation. The Doppler-determined end-diastolic pulmonary artery-to-right ventricular pressure gradient correlated well with the catheter measurement (r = 0.94). It also correlated well with the pulmonary arterial end-diastolic pressure (r = 0.92). Thus, continuous wave Doppler echocardiography was useful in estimating noninvasively pulmonary arterial end-diastolic pressures.