Accuracy and precision of three echocardiographic methods for estimating mean pulmonary artery pressure.
BACKGROUND
Pulmonary hypertension is defined as resting mean pulmonary artery pressure (MPAP) ≥ 25 mm Hg. MPAP pressure estimation by right-sided heart catheterization (RHC) is considered the gold standard; however, its invasiveness limits repeated and frequent use. The purpose of this study was to compare the accuracy and precision of three echocardiographic methods for estimating MPAP.


METHODS
We prospectively studied 117 patients with simultaneous RHC and echocardiography. MPAP was calculated by three echocardiographic methods: (1) mean gradient method (adding the right ventricular-right atrial mean systolic gradient to the right atrial pressure), (2) Chemla equation (0.61 × systolic pulmonary artery pressure + 2 mm Hg), and (3) Syyed equation (0.65 × systolic pulmonary artery pressure + 0.55 mm Hg). MPAP calculated by these three methods was compared with that obtained invasively by RHC.


RESULTS
The mean ± SD of the differences between invasive MPAP and the three echocardiographic methods were -1.6 ± 7.7 mm Hg for the mean gradient method, -3.7 ± 7.4 mm Hg for the Chemla formula, and -3.2 ± 7.6 mm Hg for the Syyed formula. Median absolute differences were 5.5 mm Hg (mean gradient), 5.7 mm Hg (Chemla; P = .45 vs mean gradient), and 6.0 mm Hg (Syyed; P = .23 vs mean gradient). Accuracy (calculated MPAP within 10 mm Hg of RHC-measured MPAP) was 81% (mean gradient), 77% (Chemla), and 76% (Syyed).


CONCLUSIONS
Echocardiographic estimation of MPAP by the mean gradient method had similar accuracy and precision compared with the Chemla and Syyed methods. The acceptable accuracy of these methods suggests that they are equally suitable for clinical use.
Aduen
Javier F
JF
Division of Pulmonary Medicine, Mayo Clinic, Jacksonville, FL.
Castello
Ramon
R
Physicians Research Associates, Jacksonville, FL.
Daniels
John T
JT
Division of Pulmonary Medicine, Mayo Clinic, Jacksonville, FL.
Diaz
Jesus A
JA
Division of Pulmonary Medicine, Mayo Clinic, Jacksonville, FL.
Safford
Robert E
RE
Division of Cardiovascular Diseases, Mayo Clinic, Jacksonville, FL.
Heckman
Michael G
MG
Biostatistics Unit, Mayo Clinic, Jacksonville, FL.
Crook
Julia E
JE
Biostatistics Unit, Mayo Clinic, Jacksonville, FL.
Burger
Charles D
CD
Division of Pulmonary Medicine, Mayo Clinic, Jacksonville, FL. Electronic address: burger.charles@mayo.edu.
D019540:Area Under Curve; D006328:Cardiac Catheterization; D016009:Chi-Square Distribution; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012372:ROC Curve