0:01

So next case is a little complex.

0:03

This is an 80 something year old patient with new angina

0:06

and known disease.

0:07

And I'll point out one thing

0:09

before we even open the case just from the scout image,

0:14

and that is that we know that they have

0:17

a sternotomy.

0:19

It's hard to see here because it's a remote sternotomy,

0:22

but just to inform you, they,

0:24

we know they have a bypass graft, uh, surgery.

0:26

And so if you scan, you wanna scan from the junction

0:30

of the first rib and clavicle all the way down in order

0:33

to catch the entirety of the left internal mammary graft.

0:36

So, and here's that scan.

0:38

And so you can see here it's a little longer,

0:40

a little more radiation, but what's needed for the patient,

0:42

um, and this is a tough case

0:44

because there aren't wires in the sternotomy.

0:46

So unless you knew there was a prior cabbage,

0:49

it might be a little bit challenging

0:51

to sort out that there had been a graft.

0:53

Um, and usually you get a wired sternum,

0:56

which is apparent even from the scout radiograph.

0:58

Uh, in this case, the history helps a lot.

1:00

Uh, so if you're going to look,

1:02

and I'll just start with the, the Lima graph,

1:04

since it's worth a look,

1:05

you wanna make sure you look at the inflow.

1:07

So here's the left subclavian,

1:09

and I'm just gonna kind of show you in two axes.

1:12

So there's a little narrowing, but nothing approaching 50%,

1:15

um, in this left internal mammary supply,

1:18

which is the left subclavian.

1:20

And then as we, um, follow the branches,

1:23

you're gonna find the, the internal mammary artery.

1:26

And you can see it's gonna, um, at some point come off

1:29

of the chest wall.

1:31

And this one's a very low lima where it comes off.

1:34

You can see the rema,

1:35

right internal memory comes off at the right.

1:37

And I'm just gonna zoom this in a bit

1:40

and you can watch that distal lima.

1:43

So very atypical bypass graft in a lot of sense.

1:46

Um, but another way to look at the vessels to turn on it.

1:48

So I'll do that for you here.

1:50

And then of course, you also have always the option to do,

1:53

um, segmented vessels.

1:55

And so if I'm trying to sort out a difficult graft, uh,

1:59

and little mip can help too.

2:00

So you have that here. Heres that anastomosis

2:03

with the distal lima.

2:05

So Lima to LED and I've sent some things out.

2:10

Um, bypass grafts are actually really well seen

2:13

on volume rendered.

2:14

I won't, um, belabor that too much on this particular case.

2:17

Uh, but um, the important thing

2:20

to note is if you have a patent bypass graft,

2:21

and I believe this is just a one vessel bypass that was, uh,

2:25

very old, uh, surgery,

2:26

it's rarely done these days, just a single vessel.

2:29

Um, unless you're doing other surgeries at the same time.

2:32

Um, but history matters.

2:33

And then following that vessel,

2:36

when you look at bypass grafts, it's also important

2:38

to look at the native arteries.

2:40

And so let's just, uh, focus on those for a minute.

2:43

I wanted to mention that the origin of the vessel matters.

2:46

And so, um, this case, uh, does have a little bit

2:50

of narrowing as the lima comes off of the subclavian.

2:54

And so I just wanted to highlight that for you, just kind

2:56

of a moderate narrowing. Um, but it is

2:58

Osteo and those are the areas that tend to get disease,

3:01

usually the distal touchdown.

3:02

Um, first, but I'm just gonna show you just with calibers

3:07

that there's a roughly 50% stenosis if you try

3:10

to measure your vessel walls.

3:11

So something

3:13

to warn the interventionalists if they're

3:14

thinking about doing a cath.

3:16

Uh, no, this patient also has a lot of stents.

3:18

Uh, you can see that there's, um, extensive atherosclerosis

3:22

and there is some plaque in the left main.

3:24

So your guard should be way up on a case like this.

3:27

In fact, this patient has stents in their, uh,

3:30

left main into the, uh, LAD and then another kissing stent.

3:34

So the kissing, because they have to be opened together,

3:37

kissing, if you will, same way we do in aortic bifurcations.

3:40

And that goes into the diagonal here.

3:43

And then I'm gonna follow this circumflex

3:45

artery with many, many stents.

3:47

Um, and rather than belabor it too much, you would know

3:49

that the, uh, stented segments would be best seen in a calf

3:53

because they have, uh, superior spatial resolution.

3:56

But this CT happened

3:57

after the cath, so I, I knew all that going in.

4:00

Um, but what we did not know is, uh, exactly

4:04

what the right coronary artery looks like.

4:06

And this might have something to do with the reason

4:08

that the patient didn't have, uh,

4:09

three vessel bypass surgery.

4:11

Um, but as you kind of bring the RCA into focus here,

4:16

you'll see that there, um,

4:18

is a tight stenosis right at the osteum.

4:21

In fact, the uh, interventional cardiologist ordered this

4:25

for planning because they couldn't see anything

4:27

beyond the sinus of el Salva.

4:29

Here's the right sinus of El Salva and here's the RCA.

4:32

So we see contrast right beyond it, how it got there, um,

4:37

is likely not antegrade.

4:39

Uh, and you can see that a lot

4:41

of plaque in the native segment.

4:43

Lemme just put some MIP on so I can kind of

4:45

enlarge this a little bit.

4:47

So native osteo disease, patent stent,

4:51

and then more native disease beyond that.

4:53

So things we like to look at when we look at a an occlusion

4:57

is, as we talked about previously

4:58

with the chronic total occlusions, the lesion length,

5:02

the degree of calcium, a lot of calcium here.

5:04

Um, another thing we often do on these cases is grab

5:07

a non-contrast scan.

5:08

So I'll just, uh, slot that in here

5:10

'cause you have the same view with just the non-con scan.

5:13

We're not gonna score the calcium.

5:14

There's a known stent, known cabbage,

5:17

but we are gonna see how much dense calcium is there.

5:19

Uh, you can do thinner reconstructions if you like,

5:22

you know, I'll show you those actually.

5:23

So little finer reconstructions than you would use

5:25

for calcium scoring, which have

5:26

to be about three millimeters for the algorithm to work.

5:28

But in this case, just more for planning purposes

5:31

and to warn the interventionalists where the calcium is,

5:34

the reason that matters so much is some of the techniques

5:36

to revascularize these involve intentionally dissecting in

5:40

the wall of the coronary artery.

5:41

You wouldn't do that where there's dense calcium,

5:43

so noncalcified and calcified plaque, uh,

5:46

right at the osteum of the right coronary artery,

5:50

a lot of plaque within the stent.

5:51

So there's in some instant stenosis.

5:53

Beyond that, what we know is likely a total occlusion,

5:56

Uh, and then, um, outflow disease beyond the,

6:00

the rest of the patent stent.

6:01

Um, and that disease is pretty extensive

6:03

and continues all the way to the inferior wall.

6:06

This is a dominant right coronary artery.

6:08

Now you you're gonna say, but I see contrast in this, uh,

6:11

posterior descending artery

6:12

and I see contrast all the way down

6:15

to the posterior left ventricular branch.

6:18

Not surprising. And so what'll happen here is the contrast

6:20

can flow in either direction,

6:21

and so this is probably retrograde flow.

6:23

I'm also just gonna show you the importance

6:25

of distinguishing blooming from, um, stents and calcium

6:29

and blooming from motion artifact.

6:31

So when I show you down here in the right coronary artery,

6:34

you see kind of air density that's kind of wispy

6:36

and along the coronary artery.

6:38

So I'll just center on that

6:39

and then I'm gonna change my phase.

6:41

And you can see here that this precise phase

6:45

without motion matters a lot.

6:46

So I'm just changing phases back and forth in time.

6:49

So now I can sharpen these vessels up

6:50

to the extent reasonable

6:53

and follow that right coronary artery.

6:55

So these are tough

6:56

because they have a lot of anatomy on the scan

6:58

and a lot of different densities of materials.

7:01

So some of it's contrast, some

7:02

of it's calcium, some of it's metal.

7:04

And then of course you can have bypass graft.

7:06

So in summary, we found a little bit of disease in the lima,

7:10

which was the only bypass graft we found.

7:13

Stunts I'm gonna ignore on the left side

7:15

that were probably patent.

7:16

Um, in part there were stents into, uh,

7:19

smaller distal vessels we know are far below our resolution.

7:22

So the spatial resolution of a ct, so

7:24

that was stents in the diagonal stents in the

7:26

distal circumflex.

7:27

And then we found that the case was right dominant,

7:30

but that there was occlusion near the osteum.

7:33

Uh, and one more look there.

7:35

So it's occlusion due to calcified plaque at the osteum

7:38

of the, um, right sinus of El Salva.

7:42

And then, um, we followed that down

7:46

and we realized there was, um,

7:48

additional lesions in the stents,

7:50

additional lesions in the native vessel beyond the stents

7:52

and that the case was right dominant.

7:54

So let's take a look at that angiogram.

7:57

So first things first, it's easier

7:59

to find a left internal mammary graft

8:00

because it comes off in a fairly standard place.

8:03

Um, but you could imagine that aorta coronary graft,

8:05

so bypass grafts that go from the aorta, uh, directly

8:09

as sewn in and then onto the heart can be more variable.

8:13

And so that can be harder to find.

8:14

You can see a lot of dense calcium in the aortic wall here.

8:16

We saw that by CT as well.

8:19

And um, what we're seeing right here is a little bit

8:21

of narrowing in the lima, the left internal mammary osteum.

8:26

I'm just gonna watch that as they get inject.

8:28

These are all hand injections. There we go.

8:31

Little bit of osteo narrowing of the right coronary artery.

8:35

I will pause it, um, at the origin just

8:38

so you can take a look at that.

8:41

So you can see a o you know, an intermediate narrowing.

8:43

Now nothing terrible. You see some clips in the, uh,

8:46

on the X-ray and then this is the left anterior descending

8:49

bypass osteum.

8:50

And so you can see that the vessel's a little tented upward.

8:52

We saw that by CT as well. That's normal. That's

8:54

How the surgeon sows it on.

8:56

I also want you just to pay attention

8:57

to late in the run here.

8:59

What you're seeing is the RCA filling distally.

9:01

So it's the PDA, um, so LAD tends to wrap around the apex,

9:05

but you see this transseptal collateral.

9:07

Uh, and that matters because blood

9:09

flow's going from left to right here.

9:11

We know the right's secluded, I showed you by ct.

9:13

Uh, and so this is late flow into the PDA

9:16

and then you can also see how densely calcified

9:19

that right coronary artery and the stent around it is.

9:21

So I'm just gonna move forward and show you the left main.

9:26

And then here's the obtuse marginal, um, you know,

9:29

those are stented and they were patent.

9:31

And here's your LAD. So things look okay.

9:33

There's gonna be competitive flow from the graft

9:35

somewhere touching down around here.

9:37

But focus on the late parts of the run.

9:39

You can see again late left to right contrast filling

9:42

of the posterior descending artery.

9:44

And then let's move over to the attempted, uh, views

9:47

of the right coronary artery.

9:49

Um, and so you can see they're nicely injecting nons

9:52

selectively into the right sinus of el Salva.

9:54

You can actually see a kind of a shadow

9:56

or a a little faint etching

9:57

where the stents are in the right coronary artery,

10:00

but that's an included vessel.

10:01

So the best you can opacify without doing a CT is those late

10:04

runs where the grafts are are filling via collaterals.

10:08

So in summary, we we saw the findings on the invasive

10:10

angiogram that we saw by the ct.

10:12

Um, but if you want to look at a, uh,

10:15

chronic total occlusion, you're gonna look at those things

10:17

with kind of modify the, the CTO planning score.

10:21

So we looked at, uh, the length

10:24

of the lesion, but also the stump.

10:25

So this is a densely calcified, um,

10:28

blunt stump makes it a little harder.

10:30

Uh, we saw that there was a, a length of an occlusion,

10:32

I won't measure it in front of you,

10:34

but it, it was about 78 millimeters.

10:36

There was more than 50% radial calcification

10:38

of several segments of these arteries.

10:41

The stent was occluded, um, within the stent

10:44

and then there was an acute bend within it.

10:46

You can sort of, uh, look here

10:48

and then, um, there were some collaterals.

10:51

So all the characteristics.

10:52

I'm gonna also show a view that we just made to help match

10:55

with the cardiac path images.

10:57

So instead of doing, um, black background

11:00

and white uh, contrast, we can just invert that.

11:02

And so that's this example here.

11:05

And so we can kind of spin it

11:06

and even make similar views that the cath would see.

11:08

So you can see these views looked a lot like a cath.

11:10

Um, that's just segmenting out the anatomy

11:12

and then inverting the image.

11:14

But it helps see the stents, it helps see the calcium

11:17

and um, the way it looks on a calf, uh,

11:19

but warns the interventionalist.

11:20

So what happened after that was, um,

11:23

the patient was taken back to the lab

11:26

and sent for a redo catheterization.

11:29

So I'll just show you one or other of those images just

11:32

because I think it's nice to see

11:34

how things look when you do a really specialized,

11:37

detailed cardiac catheterization.

11:38

Um, and this one now was done with intent to

11:42

investigate the total occlusion.

11:44

And so two catheters were put in,

11:46

one in the right and one in the left.

11:48

And when you do that, then you can opacify altogether.

11:51

So similar to a CT

11:52

Where we get contrast onto both the right

11:55

and the left systems at the same time.

11:56

Here's that cath. So you can see there's now selection

11:59

of both RCA and the LAD

12:01

and actually a third catheter selecting the lima.

12:03

And you can inject them all at once

12:05

and get, we could see for free with the ct, which is just

12:08

contrast, goes pretty much everywhere.

12:10

Can't say as much about the dynamics of it, um,

12:13

but a nice way to look and plan.

12:14

And you can see all wires already starting down.

12:16

So a very complex revascularization.

12:18

And this patient was successfully revascularized at the age

12:21

they were, uh, you didn't want to do a,

12:24

uh, invasive angiogram.

12:25

I'll also point out, um, now

12:27

that they've started the procedure here, uh,

12:29

you can see the heart is if you were looking down

12:32

the short ax of the heart.

12:33

And so you can see these septal perforators filling in in

12:35

the late myocardial blush you get in the septum

12:38

and then you can see here the, uh, circumflex

12:40

and all its collaterals.

12:41

And then those are kind of retrograde pacifying

12:43

to the distal RCA.

12:45

You see less, but you see it lower dynamically.

12:47

And then if you add catheters, you can see the same things,

12:50

difficult and complex case,

12:52

but if you work through it systematically, it's very simple.

12:54

Look at the bypass graphs, look at the native anatomy, uh,

12:57

and then just kind of go through your checklist of

12:59

what you're seeing at each level.