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Okay, this next case is the case of a 14

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year old male who presented to the emergency department with chest pain.

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Eventually, he was worked up.

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They found that he had an elevated troponin of around 70. Very high.

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And then the concern was that he had acute myocarditis.

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Cardiac MRI was ordered to confirm the diagnosis.

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This is not uncommon reason to perform cardiac MRI.

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We get quite a few referrals for this.

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And the main things that we're looking

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for are, we want to see T1 abnormalities and T2 abnormalities.

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The T1 abnormalities are going to be the late gadolinium enhancement,

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and the T2 abnormalities are going to be the edema.

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And so, we're going to start here with the cine four chamber view.

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And what you can see is that the patient has nice preserve function.

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I'll tell you that acute myocarditis

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almost every case I can think of that I've ever seen, they have preserve function.

0:56

So generally, in the acute phase,

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you're going to have pretty normal myocardial function

1:01

if it is an acute viral myocarditis

1:03

in a child. There is such an entity as chronic myocarditis.

1:07

So kids that get myocarditis, and then for whatever reason, the infection doesn't

1:11

clear. Those kids can get reduced cardiac function.

1:15

But generally, that first presentation, they're going to have normal function.

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What you can see here, though,

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and this is before we've given any gadolinium, is that there is this bright

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signal here in the lateral wall of the left ventricle.

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So remember that these SSFP images are

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a combination of both T2 and T1 weighting.

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So if you see any bright signal in the myocardium on the pre-contrast

1:39

imaging, usually that means it's going to be edema.

1:42

So that T2 signal abnormality kind

1:45

of almost like shines through the background on these SSFP images.

1:50

What is part of the standard evaluation

1:53

of patients who have myocarditis is the black blood imaging.

1:57

The black blood T2 weighted images are used to look for edema.

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In this case, this patient has really extensive and bright edema in the lateral

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wall of the left ventricle here in the subepicardial space.

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And this is a classic for myocarditis.

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Myocarditis love to involve the sub epicardium of the lateral wall,

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particularly at the base, mid cavity and apex.

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And it's often this sort of linear pattern

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where it's not so much a blob, it's not discrete nodules.

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It's really this linear pattern along

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the length of the subepicardial surface of the lateral wall.

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Now, if we move ahead to the two chamber

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cine view, you're going to see that, again, the function is preserved.

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And then when we look at the short axis

2:44

cine images, again, the function is preserved. Normal wall thickness.

2:49

But you do see that bright signal in the lateral wall shining through

2:52

again. When we move to the short axis late

2:55

enhancement images, you're going to see that there's quite

2:57

a bit of enhancement in this patient, in a pattern very consistent with myocarditis.

3:02

And that pattern is subepicardial lateral wall and inferior wall.

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Classic for myocarditis, particularly at the base and the mid cavity.

3:12

This patient's actually got basal sparing, which is sometimes a little bit unusual,

3:16

but the remainder of the case is normal and typical, where you have this lateral

3:20

wall involvement stretching around to the inferior wall

3:24

really extensive.

3:25

Even a little bit of mid wall involvement of the septum.

3:29

And that's really classic for myocarditis.

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And certainly, in the clinical setting of having an elevated troponin and chest

3:36

pain, this is basically makes the diagnosis.

3:39

I just want to show you that late enhancement on the long axis images.

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It's right here.

3:44

All this subepicardial late enhancement, it corresponds to the abnormalities

3:47

that we saw on the T2 weighted black blood imaging.

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So we have a T2 abnormality.

3:54

We have a T1 abnormality.

3:56

Those are the key components of making the diagnosis of myocarditis.

3:59

So, in summary, this patient has

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late enhancement in the lateral wall and a non-ischemic subepicardial distribution,

4:07

with edema in the same areas compatible with acute myocarditis.