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Echocardiography
in Practice
A Case Oriented Approach
by Susan Wiegers, Ted Plappert, and Martin St. John Sutton
Post-Partum Cardiomyopathy
Susan E. Wiegers, MD
A 22-year-old woman was well until 8 weeks after the
uncomplicated vaginal delivery of her third child. She
came to the emergency room complaining of severe
shortness o f breath and orthopnea. In retrospect, she had
experienced progressive exertional dyspnea since the
birth of her child. On clinical examination there were rales in both lung fields. Cardiac auscultation revealed a
normal S, and S, with a IIIIVT holosystolic murmur at the apex and a loud diastolic gallop. Pulmonary edema
was present on chest X-ray. She was admitted to the
coronary care unit where a Swan-Ganz monitor was
placed.
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Figure 86.1
Parasternal long-axis view of the left ventricle
(LV), which is
markedly dilated, as is the left atrium (LA). A Swan-Ganz
catheter (arrow) is seen as the echodense artifact in the right
ventricle. A reverberation artifact from the catheter extends
into the aortic root (AO) and the left atrium. A large pleural
effusion (PL) is present posterior to the left ventricle.
The effusion's relationship to the descending thoracic aorta
distinguishes it from a pericardial effusion. In addition,
the pericardium is visualized as an echodense border between
the
left ventricular posterior wall and the pleural effusion. |
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Figure 86.2
M-mode echocardiogram from the parasternal position. The
pleural effusion (PL) is the echolucent space posterior to
the left ventricle (LV). The left ventricular cavity is
severely dilated
measuring 6.5 cm. The fractional area change is severely
decreased consistent with profoundly decreased left
ventricular systolic function. |
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Figure 86.3
Apical four-chamber view in diastole. The left
ventricle is severely dilated and globular in shape. The
major short-axis
dimension approaches the long-axis dimension. The left atrium
(LA) and the right atrium (RA) are dilated. The pulmonary artery
catheter (arrow) is visualized in the right atrium.
(b) The same view in systole. The left ventricular ejection
fraction is severely decreased. The left atrium demonstrates
systolic
expansion, which signifies severe mitral regurgitation. The
right ventricle is not dilated, but comparison of thc systolic
and
diastolic frames demonstrates decreased right ventricular systolic
function. |
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Figure 86.4
Apical four-chamber view in systole with color flow Doppler
imaging of the high-velocity turbulent jet of mitral
regurgitation in the left atrium. The mitral regurgitation
jet is
wide at the level of its origin at the mitral valve plane and
extends into the pulmonary veins. By these criteria, the mitral
regurgitation is severe. |
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Figure 86.5
Spectral display of continuous-wave Doppler velocities across
the mitral valve. The peak velocity of the diastolic inflow
jet
is approximately 1.7 m/s. The rapid deceleration slope of the
mitral inflow rules out mitral stenosis as a cause of the
elevated velocity. The mitral valve is demonstrated to be
anatomically normal on the previous two-dimensional images.
The severe mitral regurgitation results in markedly increased
flow across the mitral valve in diastole which accounts
for the
increased velocity. The peak velocity of the mitral
regurgitation is only 4 mls which predicts a systolic gradient
between the left ventricle and left atrium of 64 mmHg. Since
the patient's systolic blood pressure was 108 mmHg, this
is further evidence of increased left atrial pressure. |
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Discussion
Peripartum cardiomyopathy can occur in primigravida as
well as during subsequent pregnancies. The presentation
may occur prior to or coincident with delivery in up to
one-half of the patients.1 This patient demonstrates a
severely dilated left ventricle which indicates that the left
ventricular remodeling has been ongoing for some time.
The left ventricular ejection fraction was estimated as 20%
by real time two-dimensional imaging.
The echocardiogram demonstrates many features of
severe mitral regurgitation. Left ventricular remodeling
has resulted in severe dilatation of the mitral annulus. The mitral
valve leaflets are unable to coapt, resulting in
severe mitral regurgitation.2 This is best demonstrated
in Figure 86.4, in which the mitral regurgitation jet appears
to originate in the left ventricle, owing to the incomplete
coaptation of the valve, resulting in tenting of the mitral
valve leaflets. The sphericity of the left ventricle, a poor
prognostic sign in dilated cardiomyopathy,3 results in
more severe mitral regurgitation.4 Various methods of
qualitative assessment have been proposed for color
Doppler mapping. A color jet area of greater than 8 cm2 in the left atrium has been shown to correlate with
angiographically severe mitral regurgitation.5 Similarly,
the color jet area may be compared to the left atrial area. A color
jet that encompasses 40% or more of the left atrium also signifies
severe mitral regurgitation.6 The diameter of the jet in the vena
contracta is also correlated with the severity of the mitral regurgitation.7 A
number of other methods for quantifying the mitral
regurgitation have been proposed, but are not in
widespread clinical use.
References
1. O'Connell JB, Costanzo-Nordin MR, Subramanian
R, et al. Peripartum
cardiomyopathy: clinical, hemodynamic, histologic and
prognostic characteristics. J Am Coll Cardiol 1986;8:52-6.
2. Kinney EL, Frangi MJ. Value of two-dimensional echocardiographic
detection of incomplete mitral leaflet closure. Am Hear1 J
1985; 109:87-90.
3. Douglas PS, Morrow R, Ioli A, et
al. Left ventricular
shape, afterload
and survival in idiopathic dilated cardiomyopathy. J Am Coll
Cardiol
1989;13:311-15.
4. Kono T, Sabbah HN, Stein PD, et al. Left ventricular
shape as a
determinant of functional mitral regurgitation in patients with
severe
heart failure secondary to either coronary artery disease or
idiopathic
dilated cardiomyopathy. Am J Cardiol 1991;68:355-9.
5. Spain MG, Smith MD, Grayburn PA, et al. Quantitative assessment
of mitral regurgitation by Doppler color flow imaging: angiographic
and hemodynamic correlations. J Am Coll Cardiol L989;13:585-90.
6. Helmclie F, Nanda NC, Hsiung MC, et al. Color Doppler assessment
of mitral regurgitation with orthogonal planes. Circulation
1987;75: 175-83.
7. Hall SA, Brickner ME, Willett DL, et al. Assessment of mitral
regurgitation
severity by Doppler color flow mapping of the vena
contracta. Circulation 1997;95:636-42.
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