Attempts at measuring pulmonary arterial pressure by means of Doppler echocardiography in patients with chronic lung disease.

In 72 patients with severe chronic pulmonary or pulmonary vascular disease pulmonary arterial pressure was measured by means of right heart catheterization. Forty three patients had pulmonary hypertension, (32 +/- 11 mmHg) and 27 patients had normal pressure (14 +/- 3 mmHg). These patients were examined with continuous wave (CW) and pulsed wave (PW) Doppler echocardiography. The retrograde systolic tricuspid valve pressure gradient assessed with CW Doppler correlated with systolic pulmonary pressure (r = 0.92, p less than 0.001, SEE 7.7 mmHg) but was measurable in only 17 of the 70 patients. The flow velocity pattern in the right ventricular outflow tract could be recorded in 68 of the 70 patients. Acceleration time (AcT) from systolic flow onset to peak velocity correlated with mean pulmonary artery pressure (r = 0.72, p less than 0.001, SEE 8.3 mmHg). An AcT less than 90 msec had an 84% positive predictive value for pulmonary hypertension. Right ventricular isovolumic relaxation time could be measured in 59 of the 70 patients and correlated with systolic pulmonary artery pressure (r = 0.69, p less than 0.001, SEE 12.4 mmHg). No single Doppler method is at the same time easily applicable and accurate in prediction of pulmonary arterial pressure in patients with chronic lung diseases.