Prediction of pulmonary arterial pressure in adults by pulsed doppler echocardiography

Abstract

Doppler echocardlography was used to estimate pulmonary artery (PA) pressure in 45 AN patients with various kinds of heart disease and the patterns were compared with those of 32 normal control subjects. Doppler signals obtained in the right ventricular (RV) outflow tract just proximal to the pulmonary valve and electrocardiogram were recorded simultaneously. Doppler velocity time Intervals were measured as follows: RV preejection period, acceleration time from the onset of the RV ejection flow velocity to the peak, and RV ejection time. Thirty patients had PA hypertension and 16 patients had a low cardiac index. The best correlation with PA pressure was achieved by the RV preejection perlod/acceleration time index (r = 0.89 vs mean PA hypertension were 93 %p and 97 %r respectively. Acceleration time correlated best with the logarithm of PA mean pressure (r = −0.88). Patients were separated into 2 groups according to cardiac index. In those patterns with a cardiac index of <2.5 liters/min/m 2, both RV preejection period/acceleration time and acceleration time were significantly correlated with PA mean pressure (r = 0.87) and log (PA mean pressure) (r = −0.87), respectively. However, the slope of the regression line for acceleration time and log (PA mean pressure) was significantly steeper than that for patients with a cardiac index of ≥ liters/min/m 2 (p <0.05), whereas the relation between RV preejection period/acceleration time and PA mean pressure In the 2 groups could not be differentiated statistically from each other. Other Intervals and ratios were less quantitative because of late systolic turbulent flow and individual variability. Thus, RV preejection period/acceleration time is a new, highly quantitative and convenient predictor of PA pressure even in the presence of a low cardiac output state.