0:00

So let's for a moment, uh,

0:02

go over some basic imaging planes and myocardial anatomy.

0:05

Um, we'll use cardiac views.

0:07

Uh, as you know, uh, the basic planes in radiology tend

0:11

to be axial, sagittal, coronal,

0:13

but everybody's heart is uniquely positioned in their body.

0:17

And so when we do a cardiac MRI ct, uh, ultrasound,

0:22

uh, nuclear exam, the planes have

0:24

to be created unique to that patient.

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And it's not as mysterious as it might initially sound, um,

0:29

but you need to use the verbiage that correlates

0:32

to this anatomy and it's very

0:33

kind of fundamental to cardiology.

0:35

Um, we have a couple of alternative names,

0:37

but one of them will be the two chamber view, um,

0:40

also called the vertical long axis view,

0:42

and especially in, uh, nuclear cardiology,

0:45

we have the four chamber view,

0:46

which can also be called the horizontal long axis view,

0:49

the ventricular short axis view,

0:50

which we did look at in the last uh, case.

0:52

And then the three chamber view,

0:54

or the three chamber long axis view, uh,

0:57

also called the paraseptal long axis view

0:59

or the left ventricular outflow tract view.

1:01

Um, so let's take a look at those

1:03

and how you might make them with a CT scan.

1:05

And I'm gonna start with basics.

1:07

This is actually up on my Twitter feed too.

1:08

I refer to it all the time in

1:09

the reading room with new trainees.

1:11

So you look up and down on your, uh, axial anatomy.

1:15

You pick a point in the center of the mitral valve plane,

1:18

you then pick a point in the, that bisects,

1:20

the left ventricular apex,

1:22

and you've made the long axis to chamber view.

1:24

Um, and from that view, you can get your next view.

1:27

You can do this as a CT

1:28

and an MRI tech is doing

1:29

that in real time when they're doing a cardiac MRI.

1:31

So again, pick a point in the mitral valve plane, uh,

1:34

left ventricular apex.

1:35

And if you're truly perpendicular

1:37

by lining those two long axis views up,

1:39

you've created the short axis view.

1:40

We talked about basal mid right, you see here, apical.

1:43

So this is the basal up by the base.

1:45

And then, um, as you come down, you can hit the mid view.

1:48

Now what we see here on the bottom left is the pseudo four

1:51

chamber view, but, and when you bisect the acute margin

1:54

of the right ventricle with that purple plane,

1:56

you define the four chamber view.

1:58

Uh, and that's a true four chamber view.

2:00

So now we're looking through the septal

2:01

and the lateral walls, only the long axis view show you the

2:04

left ventricular apex as you see

2:05

that little thin point, which is normal.

2:07

Um, if we scroll up and down

2:09

and then we take that same plane,

2:11

maintain the long axis planes, but then spin them

2:14

and bisect the left ventricular outflow tract.

2:17

As I've just done here, you now have defined a three chamber

2:20

view, the three chambers being the right ventricle,

2:22

the left ventricle, and the left atrium.

2:24

It's also a good way to look out

2:25

of the left ventricular, uh, outflow tract.

2:27

So you can, um, rewatch this video.

2:29

You can, um, play with the, the planes,

2:32

but it's actually pretty basic,

2:34

whether it's the the nuclear tech doing this for you,

2:37

the MRI automation or technologist doing this for you

2:41

or in ct, there are some algorithms

2:43

or you should really know how to just make these planes

2:45

and we'll, we'll, we'll repeat this several times

2:46

during cases that can allow you

2:49

to look at myocardial segments, the same planes

2:51

that an Echo Tech does with their wrist while they're,

2:53

uh, placing the probe.

2:55

And it allows us to then correlate things

2:56

to the segmental profusion

2:59

Expected anatomy.

3:00

And again, those territories are anterior

3:03

lateral, inferior septal.

3:04

This is a, just a mid view,

3:05

but it would apply at the bays or the apex.

3:07

And the territories then correlate

3:09

to the interseptal being LED territory,

3:12

the lateral wall being the circumflex,

3:14

and then usually the inferior wall being the

3:16

right coronary artery.

3:18

This is just an illustration.

3:19

This is, uh, an MRI, it's a first pass profusion, MRI.

3:23

And you can see here that this would be obtained over about

3:25

a minute and repeated, uh, looks with T one waiting

3:28

and we're watching contrast flow from the right

3:31

to the left heart and then into the myocardium.

3:33

And you can see an interseptal perfusion defect,

3:36

which is sub endocardial.

3:37

So it fits an ischemic wavefront gradient

3:40

and it fits a territory,

3:41

which we just saw is the interseptal walls,

3:44

which is the left anterior descenting.

3:45

So this is somebody with an LAD, uh, ischemia.

3:48

And if it's persistent, it could be an infarct.

3:50

We just have resting first pass here, so it's a differential

3:53

diagnosis.