0:01

Our next case here is a case of a 54 year old woman

0:04

who presented to the emergency department with chest pain.

0:08

She has a history of hypertension

0:10

and during her workup she was found

0:11

to have an acute SC segment,

0:14

elevation MI STEMI in her LAD territory

0:17

and went for a stent.

0:20

And then we did a cardiac MR to look for viability.

0:23

This is a couple of days post procedure, so

0:27

starting in our usual fashion here with the two chamber.

0:31

And I think already maybe you can appreciate on the two

0:34

chamber, if you look kind of at the anterior, kind of mid

0:38

and uh, apical segments, there's a little bit

0:41

of hypokinesis relative to maybe how

0:43

the motion is at the base.

0:46

So kind of LAD territory there.

0:50

Four chamber, three chamber,

0:54

little bit of again, septal

0:56

and apical wall motion abnormality here

1:01

and we'll move to our short axis sase,

1:06

pretty good wall motion there.

1:11

But here we're starting to see perhaps, you know, if you

1:16

look at the anterior

1:19

anterolateral anter septal in interseptal relative to

1:24

the more infra, lateral

1:26

and inferior segments, looks like there's probably gonna be

1:30

a bit of hypokinesis.

1:34

Not really thinning though in those segments,

1:37

but definitely not moving as well as those kind of inferior

1:41

and infra lateral segments.

1:44

And that's gonna persist as we go through here.

1:49

And here we're getting some better motion now,

1:51

the anterior lateral segments.

1:54

And here now it's really only the septal segments,

1:57

anterior septal inor segments that are involved

1:59

as we're moving more towards the apex.

2:01

Again, not thinning, but just hypokinesis.

2:08

And so the next thing that I wanna look at

2:11

is the LGE imaging.

2:13

And so we'll start with the short axis LGE imaging

2:18

moving now from base to apex.

2:20

First thing that you'll see is there's transmural,

2:23

late gadolinium enhancement here in the ant lateral segment

2:28

of the base with a little focus of hypo

2:32

intensity in here

2:35

that becomes a little less than transmural

2:38

as we move on down and kind of ends in the mid short axis.

2:42

Then the really obvious finding here is that

2:46

as we get into the mid short axis region here,

2:49

we see this large, you know, pretty much transmural focus

2:53

of LGE now with all these islands of hypo intensity,

2:58

big island of of hypo intensity here,

3:00

moving towards the apex.

3:01

So transmural, LGE, Anter septum

3:06

extending now as we get more apically into the infra septum

3:10

now inferior wall as we get to the apex.

3:12

And then just a ton of this hypo intensity.

3:15

So these are actually consistent with infarcts,

3:19

right sub endocardial in two territories.

3:22

This is gonna be LAD territory here, uh,

3:26

which she had the stent to kind of involving the septum

3:30

and then kind of the septal

3:31

and inferior aspects of the apex.

3:33

And then this is actually gonna be a circ territory acute

3:37

infarction as well.

3:40

And I just wanna show you the other thing in these acute

3:44

cases that we look at a lot are the T two maps.

3:48

So these are important. So this is a color coded T two map.

3:52

What we get with T two map is actually voxel wise level of

3:56

what the actual T two values are.

3:59

And so, you know, normally an MRI, the tissue,

4:03

it's all weighted, it's just a relative weighting, you know,

4:05

relatively T two weighted or T one weighted.

4:08

So these mapping protocols actually assign a quantitative

4:12

value to each box.

4:15

And so it allows you

4:16

to more discreetly measure what this looks like.

4:18

And so qualitatively it looks like there's a little bit

4:21

more, you know, kind of pinkish red in the septum here,

4:24

maybe up here in the interlateral segment.

4:28

And then what's nice is we can actually do a

4:31

true quantification.

4:33

So this is now the 16 segment model.

4:36

This is the base is the outermost ring,

4:38

mid is the middle ring, and then apical segments.

4:42

And it allows us to actually measure the T two

4:44

in each of those segments.

4:46

And uh, just for your reference, 60 is considered kind

4:50

of the cutoff of abnormal.

4:51

Some people say 55,

4:53

but this nicely shows that sort of in those areas

4:56

where we saw LGE, the mid anterior interseptal,

5:00

infra septal, even down here kind

5:02

of in the inferior segments.

5:04

And then in that true apex we definitely have

5:06

quite elevated T two.

5:08

And then we even have some elevated T two out here

5:10

where we saw the more CRC territory infarction.

5:13

Just to contrast that with kind of the standard

5:17

T two weighted approach image.

5:18

So this is AT two weighted dark blood image

5:21

and these are notoriously artifact prone and,

5:25

and are difficult to do well, which is one of the reasons

5:27

that I really like mapping.

5:30

But you can see here it's pretty difficult

5:32

to say if there's actually edema or not.

5:34

Here probably is, you know,

5:36

and I don't know if I window it out,

5:38

maybe it can convince you a little bit more

5:40

that this is hyperintense relative to say here,

5:43

or maybe relative to some of the skeletal muscles.

5:45

But certainly these quantitative values say that.

5:47

So now that we've got elevated T two in the areas

5:50

that there's LGE, we can call this

5:53

acute myocardial infarction with microvascular obstruction.

5:57

The other thing now that we, if we can go back

5:59

and take a look, we know that there's been reperfusion

6:03

of this LAD territory infarction from our clinical history.

6:06

So if I play this through, what it looks like is

6:09

that there's still dysfunction there.

6:12

And so this is an example

6:14

of myocardial stunning in this region.

6:17

So, you know, we have acute injury,

6:19

there's quite a bit of enhancement.

6:21

We kind of don't know which way it's gonna go,

6:23

but it's been reperfused.

6:25

So hopefully a lot of this enhancement goes away.

6:27

We imaged her in, you know, six months or a year.

6:30

But at least right now, the function is

6:33

not normal in those involved segments.

6:35

So this is an example of stunning.