Accuracy of Doppler Echocardiography in the
Hemodynamic Assessment of Pulmonary Hypertension
Micah R. Fisher1*, Paul R. Forfia2†, Elzbieta Chamera2, Traci Housten-Harris1, Hunter C. Champion2,
Reda E. Girgis1, Mary C. Corretti2, and Paul M. Hassoun1
1Division of Pulmonary and Critical Care Medicine;2Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, Maryland
Rationale: Transthoracic Doppler echocardiography is recommen-
However, some recent studies have suggested that Doppler echo-
cardiographic pulmonary artery pressure estimates may frequently
Objectives: Evaluate the accuracy of Doppler echocardiography for
estimating pulmonary artery pressure and cardiac output.
forms of PH who underwent comprehensive Doppler echocardio-
graphy within 1 hour of a clinically indicated right-heart catheteri-
zation to compare noninvasive hemodynamic estimates with inva-
sively measured values.
Measurements and Main Results: A total of 65 patients completed the
study protocol. Using Bland-Altman analytic methods, the bias for
the echocardiographic estimates of the pulmonary artery systolic
pressure was 20.6 mm Hg with 95% limits of agreement ranging
from 138.8 to 240.0 mm Hg. Doppler echocardiography was in-
accurate (defined as being greater than 610 mm Hg of the invasive
measurement) in 48% of cases. Overestimation and underestima-
tion of pulmonary artery systolic pressure by Doppler echocardiog-
raphy occurred with a similar frequency (16 vs. 15 instances, re-
than overestimation (230 6 16 vs. 119 6 11 mm Hg; P 5 0.03);
underestimates by Doppler also led more often to misclassification
of the severity of the PH. For cardiac output measurement, the bias
was 20.1 L/min with 95% limits of agreement ranging from 12.2 to
Conclusions: Doppler echocardiography may frequently be inaccu-
rate in estimating pulmonary artery pressure and cardiac output in
patients being evaluated for PH.
Keywords: echocardiography; pulmonary hypertension; pulmonary
systolic pressure; cardiac output; accuracy
Pulmonary hypertension (PH), a syndrome characterized by in-
creased pulmonary vascular resistance and remodeling, is associ-
ated with significant morbidity and mortality, which are directly
PH is currently established through right-heart catheterization,
accurate noninvasive assessment of pulmonary arterial pressure
and cardiac output (CO) is desirable both for diagnostic purposes
and to assess response to therapy.
Transthoracic Doppler echocardiography (DE) is recommen-
ded as the initial noninvasive modality in the screening and
evaluation of PH (2). Echocardiography can be used to evaluate
right-sidedchamber sizeandfunctionandthe presenceofpericar-
dial effusion, which are known to impact survival (3–5). Fre-
quently, DE is used to estimate the right ventricular systolic
pressure by estimating the pressure gradient between the right
ventricle and the right atrium using the modified Bernoulli equa-
An estimated right atrial pressure is added to this number to
approximate the right ventricular systolic pressure, which equals
the pulmonary artery systolic pressure in the absence of pulmonic
stenosis. Using this method, several investigators have demon-
strated an adequate correlation between the Doppler estimates
and direct measurements with right-heart catheterization (6, 7),
although the accuracy of DE has been called in to question in
certain clinical settings (8, 9).
Other than measuring pulmonary pressures, DE has the
potential to provide additional information important in the
management of patients with PH, such as assessment of CO, an
important prognostic indicator of survival in these patients (1).
However, little is known about the accuracy of Doppler-
estimated CO in patients with pulmonary hypertension.
The purpose of this study was to prospectively evaluate the
accuracy of DE in estimating pulmonary artery systolic pressure
and CO in consecutive patients referred to a single center for
evaluation or treatment of PH and in whom DE was performed
within 1 hour of hemodynamic assessment by right-heart cathe-
terization. Some of the results of the current study have been
previously reported in abstract form (10).
This study was conducted by the PH Program at Johns Hopkins
University. The Institutional Review Board approved the conduct of
this study, and all patients gave informed consent before enrollment.
Consecutive patients referred for right-heart catheterization for the
diagnosis or management of PH were asked to participate in the study.
Scientific Knowledge on the Subject
Although Doppler echocardiography (DE) is recommen-
ded as a screening tool for the diagnosis of pulmonary
hypertension (PH), its accuracy in estimating pulmonary
artery systolic pressure in PH patients has been questioned.
The value of DE for estimating cardiac output (CO) in
these patients has not been assessed.
What This Study Adds to the Field
This prospective study demonstrates that DE can fre-
quently overestimate and underestimate pulmonary artery
pressure in PH patients. This error is in part explained by
inaccuracies of right atrial pressure estimation and poor
Doppler imaging of the transtricuspid regurgitant jet. The
estimation of CO by DE does not appear to be reliable.
(Received in original form November 5, 2008; accepted in final form January 21, 2009)
Supported by the Johns Hopkins University General Clinical Research Center and
NHLBI P50 HL084946 (P.M.H.).
Correspondence and requests for reprints should be addressed to Paul M.
Hassoun, M.D., Division of Pulmonary and Critical Care Medicine, 5501 Hopkins
Bayview Circle, Baltimore, MD 21224. E-mail: firstname.lastname@example.org
* Present affiliation: Division of Pulmonary, Allergy, and Critical Care Medicine,
Emory University, Atlanta, GA.
†Present affiliation: Division of Cardiology, University of Pennsylvania, Philadel-
Am J Respir Crit Care Med
Originally Published in Press as DOI: 10.1164/rccm.200811-1691OC on January 22, 2009
Internet address: www.atsjournals.org
Vol 179. pp 615–621, 2009
evaluation of pulmonary hypertension by a pulsed Doppler tech-
nique. Circulation 1983;68:302–309.
27. Chemla D, Castelain V, Provencher S, Humbert M, Simonneau G,
Herve P. Evaluation of various empirical formulas for estimating
mean pulmonary artery pressure by using systolic pulmonary artery
pressure in adults. Chest 2009;135:760–768.
28. Chemla D, Herve P. Estimation of mean pulmonary artery pressure:
simpler than expected. Chest 2008;133:592–593.
29. Dabestani A, Mahan G, Gardin JM, Takenaka K, Burn C, Allfie A,
Henry WL. Evaluation of pulmonary artery pressure and resistance
by pulsed Doppler echocardiography. Am J Cardiol 1987;59:662–
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