Evaluation of Pulmonary Hypertension with Pulsed Doppler Ultrasound

We examined a pulsed Doppler index between the acceleration time and right ventricular ejection time (derived from the pulmonic flow velocity pattern) for noninvasive evaluation of pulmonary hypertension. Ninetyeight patients were analyzed prospectively prior to cardiac catheterization; invasive pressure data were then compared to this Doppler index. Using a mean pulmonary arterial pressure >20 mm Hg, and pulmonary vascular resistance > 120 dyn•s•cm^–5 to define the presence of pulmonary hypertension, it was found that the best noninvasive correlation with the extent of pulmonary hypertension occurs when the Doppler index is compared to the logio of pulmonary vascular resistance. An index of <0.29 correctly identified all patients with increased pulmonary vascular resistance, and an index of >0.39 always correctly predicted subjects having normal pulmonary vascular resistance. This Doppler index is, therefore, quite useful to accurately and noninvasively monitor pulmonary arterial pressures in patients who need frequent sequential evaluations.