Thesis (M.Sc.)--Chulalongkorn University, 1991

Measurement of pulmonary artery pressure (PAP) in clinical practice is very important. The purpose of this study was to find the best parameter from two dimensional and pulsed wave doppler echocardiography to assess the pulmonary artery pressure compared to that measured from cardiac catheterization. Echo cardiography and cardiac catheterization were performed in 30 adult patients age 16 to 71 years (mean 41.40 +12.94 years) with various kinds of heart disease. The doppler sample volume was placed in the main pulmonary artery just distal to pulmonic valve with electrocardiogram recorded simultaneously. The best correlation was found between AT/ET ratio and diastolic pulmonary artery pressure ( r = 0.90, P < 0.001) and also systolic and mean PAP with r = -0.85 both ( P < 0.001). The formula that can be used to assess the pulmonary artery pressure were as follow, systolic PAP = 146.81 – 243.02 (AT/ET), diastolic PAP = 67.35 – 114.16 (AT/ET) and mean PAP = 95 – 156.73 (AT/ET) The results indicated that right ventricular systolic time interval (RVSTI) detected from pulsed wave Doppler echocardiography was a good noninvasive technique that can be used to measure the PAP.