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Echogenic focus in the fetus's heart (golf ball)
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What is this and what is its significance?
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An echogenic focus is an ultrasound reflection of the thickening of one of the tendonous
cords that hold the heart valves. Such a thickening does not interfere with the
normal functioning of the valves and it has no significance for the structure or
functioning of the heart if no other
heart defects are present.
It is relatively common. In about 5% of fetuses one or more echogenic foci, visible
as bright spots in the ventricle of the heart, are detected by ultrasound. This
spot usually appears in the left ventricle of the heart, but in some cases it is
present in both ventricles. Because of its white color, it is called an echogenic
focus or a golf ball (because of its shape).
Although the focus itself has no significance, a number of studies have shown that
it indicates an increased statistical risk for a fetus with Down syndrome. Some studies have reported a two to
fourfold increase in the risk. Conversely, there are other studies that have not
demonstrated a significant increase in the risk for Down syndrome. The situation
is different in cases where the echogenic focus is associated with other findings.
In these cases there is a significant increase in the risk for chromosomal problems in general, not only for
Down syndrome.
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The echogenic focus as part of a group of parameters for evaluating the statistical
risk for chromosome disorders
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There are several parameters that establish the statistical probability for Down
syndrome, so the presence of an echogenic focus can be considered as part of the
aggregate of these parameters. Normal
nuchal translucency, young maternal age, absence of other signs or defects
on ultrasonography, and a normal biochemical screening result are all
factors that indicate a significantly reduced risk for Down syndrome.
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What should be done if this is diagnosed?
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There are differing opinions.
Amniocentesis (or
chorionic villus sampling) is undoubtedly the only test that can categorically
rule out chromosome disorders.
However, it is neither medically indicated nor recommended that every pregnant woman
should undergo amniocentesis - only those who are at high risk of having a specific
problem that can be examined by this test (see information sheet titled: Why is there no medical recommendation for amniocentesis
in all cases?).
Most opinions hold that in the majority of the cases in which the echogenic focus
in the heart is the sole finding, and taking into account the other parameters mentioned
above, which do not raise the risk for a chromosome disorder, the weighted risk
is not in the high-risk range for which amniocentesis is indicated.
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However, it should be noted that at the present time there are no accurate statistical
data that allow for a precise calculation of the weighted risk taking the results
of all the tests into account.
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For practical purposes:
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A directed 3rd level ultrasound scan in order to look for additional defects should
be performed in the 22nd week of pregnancy. If any other defects are found, then
amniocentesis should be performed.
The "gold-standard" threshold for recommendation of amniocentesis is a risk of Down
syndrome greater than 1:386 based on the results of the biochemical marker screening
tests, and when the weighted risk is equal to or higher than this amniocentesis
is generally recommended. However, the presence of an echogenic focus in the fetus's
heart may statistically increase the risk of Down syndrome. Therefore in these cases
some physicians suggest that this should be integrated with the results of the biochemical
screening tests and the new threshold for recommending amniocentesis is a risk for
Down syndrome of greater than 1:1000 in the biochemical marker screening tests.
If other abnormal findings are also present, these guidelines are insufficiently
established and the woman should be referred for genetic counseling.
In genetic counseling, the necessity for amniocentesis can be assessed. It is particularly
important to recommend counseling in all cases where other signs or defects are
present, because the risk for a chromosomal or other syndrome is then significantly
increased, and the advisability of performing further tests should be discussed.
In cases in which it is suspected that the echogenic focus is associated with the
heart's muscular wall, it may be worth performing fetal echocardiography between the 22nd and
the 24th week in order to rule out a tumor (a very rare condition).
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