Fetal Echocardiography

Truncus Arteriosus

And the bottom line is there's just one large outflow tract
that we see flow is in the right direction here.
It's coming out of the heart
and then down the descending aorta.
And you can see two little pulmonary
arteries coming off of here.
And so this is a truncus
and this is a sweep showing from the four chamber view
as we come up that you can only see one outflow tract.
There. It is one large outflow tract, probably a large VSD
or cushion defect in here as well.
I think there is a cushion defect right there. One AV valve.
It's a complex congenital heart abnormality,
takes a multi-stage repair.
This is showing the color flow proving
that the two chambers connect to each other
and that this truly is, uh, a large VSD or cushion defect.
And then as we sweep towards the outflow tract,
you can see just one vessel, uh, here,
and the flow is coming out of the heart.
This is blue in this case, uh, showing that
that's coming away from the heart, meaning out of the heart.

Ductus Dependent Lesions

And so again, the ductus dependent lesions.
Tetrology can be depending on the degree
of pulmonary hypoplasia.
And then transposition most certainly is, uh,
especially if there's no a SD or VSD.
And these are the ductus dependent lesions.
And this is extremely important,
and this is probably the single biggest contributor, uh,
to decreasing neonatal mortality, is to recognize, uh,
what is, uh, a ductus dependent lesion
and then treating the neonate, uh, with prostaglandins
or other medications as necessary to keep the ductus patent.

Septation and Inlet Abnormalities

And again, this is, uh, the alignment, uh,
when septation occurs.
Uh, this is the normal septation, uh, with the AV valves,
uh, straddling the septum.
Uh, but there are various complex heart defects where both
inlet valves are in the right ventricle
or even more, uh, rare.
Very rare is when both inlet
valves are in the left ventricle.
So these are the inlet abnormalities.
You can have a double outlet, right? Ventricle.
You can also have a double inlet, right ventricle.
And this has to do with looping
and then the symmetry of where septation occurs.
And this is what results in a hypoplastic left heart.
This is what results in a hypoplastic right heart.
And then it's a matter of where the valves are situated.
Uh, and this of course, uh, increases the complexity
of the repair of these defects.
And again, this is, uh, another schematic of that.
This is, uh, the atria,
the AV valves basically being balanced here and appropriate
or overriding to one side or the other.
So this is just another diagram of the same thing.
And you can see that if you look at this particular cine
loop, you'll see that the AV valves
are both feeding basically into one ventricle here.
So this is really the right ventricle.
And you can see both AV valves.
So that's a double inlet valve.

Ebstein's Anomaly

Now finally, Epstein's anomaly is a slightly different type
of defect, and this is basically an inferior, uh,
displacement of the mitral valve
or the tricuspid valve insertion.
Uh, and this results in what's, uh,
an enlarged right atrium.
Some people refer to this as an atrial ventricle.
Uh, but this is a big defect, an in effect,
this diminishes right ventricular outflow, uh,
and it diminishes cardiac output on the right side.
And, uh, this car is right fid, uh, heart uh, failure.
And here you can see the right atrium.
And instead of the AV valve inserting here,
which would be normal, it's displaced apically,
uh, significantly.
And this is really what Epstein's anomaly, uh,
is more than the right atrium enlargement.
It's this displacement of the valve, uh, that's significant

Bicuspid Aortic Valve

bicuspid aortic valve.
It's very difficult to diagnose in utero.
We usually don't see it normal tricuspid valve.
Uh, sometimes you might see this fish mouthing, uh,
in the aortic valve.
This is a postnatal exam.
It's easier to see here, and that's a bicuspid aortic valve.
But prenatally, this is very difficult to diagnose.
It's associated with coarctation of the aorta.
And that's a significant, uh, thing to look for.
Uh, and if you happen to see a CoARC of the aorta,
then you look for the bicuspid aortic valve
since they are associated.

M Mode in Fetal Echocardiogram

I mentioned that M mode is part of the fetal echocardiogram,
and this is what an M mode strip would look like when
we look for arrhythmias.
And you can see, uh,
these are the ventricular contractions here.
These are atrial contractions, these very subtle ones.
As we angle, we try to get an angle through the heart
where we can see the atrium and the ventricle in one plane.
And, uh, one-to-one correspondence is normal.
If you're seeing more atrial contractions than ventricular
contractions, uh, then that's an AV block.
Uh, if it's too fast, greater than 175 beats per minute,
that's tachycardia.
If it's too slow, uh, less than 90 beats per minute,
that's a bradycardia.

Tachycardia and Heart Failure Example

And sometimes you can just get the feeling
that the heart is just beating away way too fast.
And if you look at this cine loop,
you can just see this heart is hardly contracting
and it's beating away.
This was about 200 beats per minute.
And there's a pericardial effusion was actually causing
heart failure in this fetus.
Big heart. This is just a huge heart.
And this was an interesting case.
Uh, this was a twin and the other twin had died in utero.
And so this twin is then actually perfusion the other twin,
and the heart gets enlarged.
And this baby starts going into heart failure, uh,
because it's got such increased
after load resistance that it's actually pumping, uh,
two circuits, both twins.
And this heart was just huge.
It's occupying the whole thorax here.

Cardiac Tumors: Rhabdomyoma

Tumors are very uncommon of the heart.
And the one we usually see is rhabdo myoma.
And you'll see that as an echogenic mass.
And a lot of times there's lots
of little echogenic masses on these that we may
or may not be able to resolve.
And there is an association with tube sclerosis in these.
So if we see this, we'll look at the kidneys, uh, for angio,
my lipomas, and then we'll look at the head as well
for periventricular calcifications.
And this is associated with a seizure disorder.
And, uh, in addition, uh, if this chamber is full of tumor
and it can't feel with blood, then this fetus is at risk
for going into heart failure, uh, when it's born,
because basically there's no inflow, uh, occurring her.
So it's kind of a, a preload reduction, uh,
that results in heart failure.

Other Associated Defects

And then there are other defects
that are not exactly heart defects per se,
but you can have a large anterior abdominal wall defect, uh,
where the heart is actually located outside of the body.
And there is a thing called panal of re, uh, which is, uh,
uh, the heart being located outside of the body,
but there's a large anterior abdominal wall defect.
So you have an empha seal,
the diaphragm doesn't form properly.
The pericardium obviously hasn't formed correctly since the
heart is outside and you have heart defects
associated with these.
And these can be repaired.
In the old days, uh, it wasn't possible to repair these,
but now, uh, they can be repaired.
Here's another one. The heart is out, the liver is out.
Here's a large anterior abdominal wall defect,
and this was a penology of cantrill.
Another one, a lot
of polyhydramnios in this particular case.
Here's bowel, here's liver, A lot of things sticking
outside of the abdominal body.

Conclusion

So in conclusion, uh, there is a difference
between screening heart views, which is what we all do,
and each view has a specific thing that we're looking for.
Uh, but a true fetal echocardiogram is a slightly, uh,
different exam that includes mo doppler
and color flow imaging.
It's extremely important to take cine clips,
and this is how we make most of our diagnoses.
The single most important thing
to know is which lesions are the ductus dependent lesions
and how we go diagnosing these, uh, and why we miss defects.
We're never gonna be a hundred percent accurate,
uh, at seeing these.
And unfortunately, these are so complex, uh,
that sometimes we just can't see everything that's wrong
with the heart, uh, in utero.
And I think it's very interesting that most
of these heart defects, uh, do reflect the embryology of,
uh, cardiac development, uh, evolutionarily
as we evolve from worms and,
and ultimately, uh, fish, uh, amphibians and reptiles.
Thank you very much.