Doppler echocardiography was recently developed for obtaining a flow velocity profile at any point in the cardiac chamber. A pulsed Doppler technique combined with cross sectional echocardiography was used to examine the flow velocity pattern in the right ventricular outflow tract in 32 patients with chronic pulmonary disease (CPD) and in 15 healthy subjects as controls. All patients underwent cardiac catheterization. Pulmonary flow velocity profiles in the right ventricular outflow tract were recorded simultaneously with electrocardiograms and pre-ejection periods (PEP), right ventricular ejection time (RVET), acceleration time (AT), and calculated PEP/RVET, AT/RVET were determined. All normal subjects had "dome-like" flow velocity patterns with a peak flow at the midsystole. In patients with CPD, there was a significant correlation between log10MPAP (mean pulmonary arterial pressure) and AT/RVET, the coefficient being r = -0.623, between PVR (pulmonary vascular resistance) and AT/RVET (r = -0.52), and between SVI (stroke volume index) and PEP (r = -0.645). Complications of pulmonary hypertension in CPD were relatively mild, but the pulsed Doppler technique was found useful for evaluating pulmonary arterial pressure and other right heart hemodynamics of CPD patients.
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