Abstract:
Objective To estimate the pulmonary vascular resistance by Doppler echocardiography in patients with pneumoconiosis at stage three, and to explore the clinical value of this appliction in estimating pulmonary vascular resistance.
Methods Thirty-eight patients with pneumoconiosis at stage three and forty normal control subjects were enrolled. Measurements by Doppler echocardiography included right ventricular outflow tract diameter (DRVOT), time velocity integral of right ventricular outflow tract (VTIRVOT), tricuspid regurgitation peak velocity (TRV) and regurgitation pressure, systolic peak velocity of tricuspid annulus (tSm), and left ventricular ejection fraction (LVEF). Pulmonary vascular resistance (PVR) was estimated by the following two methods:PVRecho1=5.19& #183;TRV2/VTIRVOT and PVRecho2=3 698-1 227& #183;ln(tSm). Pulmonary artery systolic pressure (PASP) was also estimated. Heart index (CI) was calculated by CI=right cardiac output (CO)/BSA. All indicators were compared between the two groups.
Results Compared with the normal control group, the PASP, PVRecho1, and PVRecho2 were significantly higher in the stage three pneumoconiosis patients(74.99& #177;18.04) mmHg vs. (30.98& #177;2.83) mmHg, (6.30& #177;1.68) Wu vs. (1.45& #177;0.29) Wu, (607.22& #177;76.74) dynes/cm5 vs. (385.51& #177;76.95) dynes/cm5, respectively, all P<0.01. So were the DRVOT and TRV(25.07& #177;1.05) mm vs. (20.84& #177;0.67) mm, (3.55& #177;0.18) m/s vs. (2.24& #177;0.13) m/s, respectively, both P<0.05. However, the VTIRVOT and tSm were lower(13.44& #177;1.20) mm vs. (15.46& #177;0.65) mm, (12.71& #177;0.59) mm vs. (15.09& #177;1.05) mm, respectively, both P<0.05.
Conclusion Estimating pulmonary vascular resistance in patients with pneumoconiosis at stage three by Doppler echocardiography is noninvasive and convenient in operation, which is expected to provide useful information for relevant physicians.