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All right, so the first case we're gonna look at in this

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course is a 73 year old man who had a TAVR performed

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and also had coronary artery bypass grafting.

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It's got a history of myocardial infarction

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and I want to use this case as, as an example

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to illustrate the difference between transmural

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and Nont transmural infarction.

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And then we'll actually look at some

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coronary artery territories.

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So as you'll see, uh, is a theme

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whenever we look at any of these cases, I,

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I at least always start with the functional imaging

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and start here with the long axis view.

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So this is a two chamber view.

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A couple of points while we're going through,

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again related to two chamber.

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The two chambers we see are the left ventricle here,

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the left atrium here.

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I always like to point out the left atrial appendage,

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which is a good place to just keep an eye out for thrombus.

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And then as I scroll through this on my syn a clip,

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you can see actually in this case this is the mitral valve

0:59

here and we can see that as I scroll through,

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there is actually some mitral regurgitation.

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So just a couple of basic cardiac MR points,

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not really related to ischemic cardiomyopathy.

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And then what we can see as I get

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to end diastole here, something about here we can see

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that there's actually wall thinning of this sort

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of apical anterior segment, true apex

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and then down into the inferior aspect of the apex

1:28

and probably some wall thinning here

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and what ends up being the basal inferior segment.

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So we'll investigate those further on

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the short axis imaging.

1:36

Moving on to our next long axis view,

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this is the three chamber view.

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So just again for anatomy, basic anatomy orientation,

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left ventricle, left atrium,

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this is the aorta in this patient.

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This is his TAVR valve

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and this is the right ventricle right here.

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We do see some susceptibility artifact in the sternum

1:54

related to sternal wire sutures from his prior cabbage.

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But uh, again, we're seeing kind of a very similar look here

2:03

where we have mitral regurgitation

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and a lot

2:07

of regional wall motion abnormalities and thinning.

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In this case, just kind of based off of the orientation

2:14

of the three chamber, we again see that they're thinning

2:17

an kinesis at the true apex and then a little bit here

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and sort of the apical aspects of the eth intercept.

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Moving on to our last long axis view,

2:28

this is a a four chamber again as an anatomy overview.

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Left ventricle here, left atrium here, right atrium,

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right ventricle mitral valve, tricuspid valve here.

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This is the aorta descending aorta back here.

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And as we're watching again,

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we see some regional wall motion abnormalities,

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probably seen better on some of the other views.

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This is a nice overview to take a look at mitral

2:57

and tricuspid valve disease

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and it's really the, the view

3:00

that we get the best look at the long axis function

3:03

of the right ventricle.

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So a couple of kind of key points on cardiac Mr

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Next I'm gonna start in on our short axis view.

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So as we, we move through the short axis,

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at least the way these cases will be set up,

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we're gonna move from base to apex.

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And so for example, on this view, we start to see the aortic

3:24

valve prosthesis.

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So you kind of know we're at the distal base here

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and as we work, this is the mitral valve

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that we're kind of seeing the leaflets on.

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And as we start to work through, I think you'll start

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to appreciate

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that there's some wall thinning here in the basal infra

3:39

septum and also probably kinesis

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what I would term kinesis there.

3:44

And we really start to see it nicely in this view now

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involving not only the inferior wall

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but also the infra septal aspect

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here at the left ventricle thinning and,

3:55

and probably kinesis at least of this and

3:58

and severe hypokinesis or kinesis of the infra septum there.

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Keep working our way down.

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Kind of see continued kinesis of the infra septal wall.

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Notice up here we, we see kind of hypokinesis of all

4:10

of these segments and particularly this interseptal segment

4:14

but not a lot of wall thinning there, right?

4:17

So more of the same.

4:18

Now we're starting to get a little bit more apically and,

4:21

and you kind of get the sense

4:22

that all segments almost circumferentially are starting

4:24

to be quite thin and,

4:25

and we have more involvement of the anterior segment here

4:29

and some of the anterior septal aspects here with thinning

4:33

and kinesis and then some sort of hypokinesis of the septal

4:37

and lateral segments here, kind of global hypokinesis

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and thinning as we move more, more

4:43

and more towards the apex.

4:46

And then on down.

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So now we have a pretty good overview of the

4:52

wall motion of this patient.

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So let's look at the LG images.

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This is kind of, you know,

4:58

when we're thinking about infarcts

4:59

and viability imaging, obviously the LG imaging

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is gonna be really crucial.

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So here's our LG imaging

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and I'm gonna start up here at the base

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and walk kind of slice by slice.

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And so first thing we note is as we start to get into kind

5:15

of the basal inferior segments here we see sub endocardial,

5:20

late gadolinium enhancement involving the basal

5:24

inferior segment and infra septal segments here.

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And I would describe this particularly,

5:29

I think this is a nice example as transmural,

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you can really see that, we know this was thin

5:35

on the semi imaging,

5:36

but you can really see there's like a pretty dramatic sharp

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cutoff here between these two sites.

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And you know, if this didn't have LGE,

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you would really see myocardium all through there.

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So that's a transmural infarct.

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I don't see anything left over

5:50

probably still definitely greater than 50% near transmural

5:53

here in this segment starting to be a little

5:56

Less than 50% here as we get more

6:00

apical here in that inferior segment.

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And then we kind of pick up a little few spots of LGE

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that are a little bit more focal kind of RV insertion point.

6:08

But really this is an example of a transmural infarct

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and based off of what we know from our 16 segment model,

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this is in the RCA territory,

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it fits really nicely in the RCA territory.

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So this is an example of a non-viable trans bural RCA

6:26

infarct on this patient.

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But that's not all that we see in this patient.

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And this is important, you know, kind of satisfaction

6:33

of search idea to keep in mind.

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So the other thing, if we move back here towards the base

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and start to look at a few other regions, you start to see

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as we get here towards the basal to mid kind

6:45

of anter septal segment, we start

6:46

to see some sub endocardial lake GA lame enhancement.

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Not quite as dense as this.

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Our intense as the RCA infarct is in terms

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of just overall signal

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and we maybe see a little dot

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of what's called hypo intensity.

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And this may be microvascular obstruction, which we'll go

7:04

to later in the course,

7:06

but this is still sub endocardial,

7:09

late gaden lay enhancement.

7:10

So kind of is following more of an ischemic, more

7:13

of a vascular kind of infarct type pattern.

7:16

But notice in this case, first of all, there wasn't

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as much wall thinning on the CNA images that I showed you.

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And here we can kind of make out like, you know,

7:25

there's still some normal myocardial kind of hypo intensity

7:30

that isn't totally taken up by LGE.

7:33

You know, for example, this image it looks like, you know,

7:35

maybe this is kind of the extent of LGE right here.

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So this would be an example of a non transmural infarct.

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And so kind of you see on the same slide here, an example

7:45

of a transmural infarct in probably what we would at least

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estimate to be roughly 50% maybe.

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And perhaps this is more of an acute process.

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So this would be a one that we would say is,

7:58

has a higher likelihood of functional recovery

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with revascularization in this patient.

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The last thing that I want to show you

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in this particular case,

8:07

'cause it can be tricky if you're just looking at the short

8:10

axis images, the long axis images can actually be quite

8:13

helpful as well.

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So here's a two chamber LGE image

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and one thing that is helpful is you can kind of see like,

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okay, here is actually the extent of that inferior LGE.

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It really truly is kind of truly transmural here.

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So you get a different view, a long axis view kind of

8:34

of the LGE, but you also get the sense down in some

8:38

of those areas of the apex that were totally thinned out,

8:41

that there is really no myocardium here.

8:44

That's normal. So this is also gonna end up being a

8:47

transmural infarction in the true apex,

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which is usually supplied by the LAD.

8:54

So you kind of got LAD disease here, some

8:57

of which is viable in the basal anter septum.

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And then this more distal LAD disease

9:02

that you probably only see well on these long access views

9:05

as non-viable.