0:00

So we're gonna do this, uh, case, uh,

0:03

case one for this week.

0:06

This was probably the hardest case for the course

0:09

because of the complexity of the question being asked

0:14

and really what the goal of this is.

0:15

Now, in this particular case, I think, you know,

0:20

the most important thing for us to really focus on,

0:23

and the goal for this is just to kind

0:24

of go over the evaluation of bioprosthetic valve dysfunction

0:28

and how cardiac CT does

0:29

and what we can do for pre-procedural planning.

0:33

So in this case, you know, as this case

0:34

of seven 4-year-old male had a previous aortic valve

0:38

replacement, and we provide you the size of the valve,

0:40

it's a 23 millimeter, uh, Carpentier Edwards magnet 3000.

0:46

And, you know, the clinical VEA shows

0:48

that the patient's having symptoms of shortness

0:50

of breath fatigue to kind of, kind

0:52

of put you along into the evaluation of the cardiac function

0:54

and valve prosthetic dysfunction on the echo, suggesting

0:58

that this valve's abnormal.

1:00

So in this particular case, what we wanted

1:02

to focus on is like how do we evaluate this valve

1:05

and how do we look at it?

1:06

So one of the first things that I did is I loaded,

1:10

in this particular case,

1:12

the cardiac phases at 10% intervals.

1:15

You can, I, I don't know if yours has the same issue

1:18

as mine, it shouldn't, but mine would not let me load all,

1:22

you know, 20 phases at 5% intervals,

1:25

but you don't necessarily need it,

1:27

meaning 10% intervals should be sufficient for you to do it.

1:31

If you wanted to do ejection fraction assessment,

1:33

you know you need in diastole, which is zero,

1:36

and then an Sicily, which would be 95 rather than 90%.

1:40

So on that particular case,

1:41

you may wanna load just those two phases

1:44

to get those volumes assessed.

1:47

Regardless of that, you know, here in this particular case,

1:50

we're gonna be focusing on step part one of this

1:54

and that is looking at the valve itself,

1:56

which is the main purpose of this.

1:58

This study was not optimized for the evaluation

2:00

of the coronary arteries, so it kind

2:03

of freeze you from having

2:04

to look at the coronaries in detail.

2:06

One of the first things you wanna do when you look at this

2:09

case is to look at the valve

2:11

and trying to line up your, your cross hairs

2:15

along the actual valve itself.

2:19

Ideally, when you're looking at this,

2:21

you wanna be in a preferably systolic phase.

2:26

I usually recommend end systole as a good starting point.

2:29

So we're talking like 40%, uh,

2:33

50% type thing.

2:35

And here at 50% if you look at this screen, you can see

2:38

that the valve is completely closed.

2:41

And what you're gonna want

2:42

to do is you're gonna wanna line up your cross hairs

2:45

to be aligned with the valve plane gonna start being able

2:49

to scroll through the leaflets to assess.

2:52

Now bioprosthetic valves, uh, native valves,

2:58

all these valves themselves always have

3:00

to be assessed at the tip of the leaflet in order for you

3:04

to kind of assess for mulching and wall thickening.

3:08

Now the expert consensus statement for the valuation

3:11

of these valves occurs you to use your planes

3:13

and to line 'em up in this section along each

3:18

valve plane to be able to rotate through.

3:21

See how in this swipe we're looking at this leaflet.

3:25

But in this one we're essentially looking at both

3:28

of these leaflets, perpendicularly and diagonally.

3:32

And what we're gonna try to do is I adjust my window levels

3:35

to really kinda allow the valve

3:39

to be visualized in detail

3:41

and kinda assess the degree of thickness.

3:44

A normal bioprosthetic valve,

3:45

a no normal native valve should be

3:47

so thin without significant degeneration

3:50

or thickening that it should be very difficult

3:52

for you to visualize.

3:54

In this particular case,

3:55

not only can you visualize the valve,

3:57

you can actually see it relatively well

3:59

and easy in in in its structure and its function.

4:03

Once I start playing, I usually like to scroll

4:06

through the image to kind of assess

4:08

how the leaflets themselves are moving

4:10

and to assess for restriction, I start with movement

4:14

and then I work my way towards towards the structural.

4:18

Here you can see that there is restricted motion,

4:21

particularly this leaflet correspond

4:23

to the left non coronary to the left coronary cause leaflet,

4:26

as well as a little bit more on the right coronary cause

4:28

leaflet, less so on the one in the non coronary.

4:32

Then as you continue to scroll further down towards the base

4:35

of the ring, you can actually start assessing a lot of this

4:39

calcification at the, at the base of the leaflets.

4:42

And you can see here the degree

4:43

of calcification calcification in bioprosthetic valves is

4:47

almost always an end product of chronic thrombosis.

4:52

Not necessarily like chronic clot,

4:54

but this hyper continuation leaflet thickening

4:56

and the fibrosis that comes as a result of it.

4:58

So it's a marker of that.

5:00

Once I've identified that, I usually like to scroll

5:03

through the leaflets themselves,

5:04

like I said in this same orientation

5:07

and kind of sets the degree of leaflet thickening

5:10

based on the extent of calcification.

5:12

You can see that there's calcium extending just from the

5:15

base, almost a little bit more than 50%

5:18

of the leaflet length as well as thickening

5:21

or extending all the way to the leaflet.

5:23

And that is how we assess the degree

5:25

of high attenuation leaflet thickening in the range of mild,

5:30

minimal, mild, moderate, and of course severe.

5:33

So you can assess that here.

5:35

You can see this on the same leaflet,

5:36

you can see less calcification here, more of

5:39

that low attenuation leaflet, thickening,

5:42

and then some of the calcification near the tips.

5:44

You do the same thing for this other two leaflets.

5:47

And again, you look at the degree of calcification

5:50

and the degree of restricted leaflet mobility.

5:52

So that's where you can assess that there.

5:55

The valve itself,

5:56

and as you read in the description right there is uh,

6:00

abnormal leaflet ticket in calcification on two

6:03

of the leaflets, the right coronary cus the left

6:06

and the non coronary cuss leaflets.

6:08

And then there is restricted motion like what we said,

6:12

like hyper continuation, affecting mobility.

6:15

Now once we have this,

6:17

then we're gonna get back into the approach that we did

6:20

with the TAVRs where we're gonna say, okay, we need

6:23

to replace this valve,

6:24

but I need to see when the valve is most open here you can

6:28

see that at 30% the leaflets are opening at their widest

6:31

dimension and then more importantly, where can I embed

6:35

or what that valve is going

6:37

to look like when I embed a valve.

6:39

So what we're going to do is we're gonna change our workflow

6:44

to the TAVR workflow.

6:46

Now what's different in this particular approach is yes,

6:49

you can click on the root and the overview.

6:51

I'd like you to just, once you've oriented

6:55

start moving your planes to get

6:57

to the ring at the base of it.

6:59

See we're gonna scroll down

7:01

and come right here at the true base and line things up.

7:06

The surgeon or whoever implanted this did a relatively good

7:09

job kind in putting this leaflets in an orientation that'll

7:13

make it easier for you to, to line up in that plane.

7:17

So instead of going through the oblique measurements,

7:19

which you could say you click oblique

7:22

and then you end up all disoriented here

7:24

'cause the machine really wants to help you.

7:26

It's an option you can do and not against it,

7:29

but it's something that, it's a step that I don't want you

7:31

to necessarily feel that you have to absolutely follow

7:35

for you to, to do this case.

7:37

So you come back up here, you kind of see your ring

7:41

and you're gonna go to the oblique measurements.

7:43

Now remember the landmarks remain the same.

7:45

We're gonna start using the triangle and go to and

7:49

and with the left.

7:51

And again, you are not gonna be as focused here

7:54

as you are on on the, on the leaflet themselves.

7:59

You're just gonna wanna come to the bottom

8:00

of like the actual ring,

8:02

like really the lowermost or of the ring.

8:04

They're gonna come back up here.

8:07

And then on the right you're gonna do kind of the same thing

8:09

and you're using this to kind of orient you.

8:12

So you can see how this, uh,

8:14

right cusp leaflets right here on the right.

8:18

And then you're gonna come here towards the left

8:20

and again, kind of follow it to where you are

8:23

most oriented at the bottom.

8:25

And you see how here we're kind

8:27

of oriented in this direction.

8:31

Once you find this direction, right, you're going to then

8:35

double click on this landmarks.

8:37

I would change this from from full to a half.

8:41

So you can start seeing the anatomy

8:44

and I would start adjusting my my window level

8:47

so you can start seeing the transparency to,

8:50

to see the alignment of your, of your valve. Now if you

8:54

Feel that your landmarks are off

8:58

or they're not right where they need to be,

9:01

you can always come back and and erase them.

9:04

You have two ways you delete all

9:06

and this will allow you to move it

9:07

and kind of correct for this uh, movement here, right?

9:11

So we're gonna hit, uh, left,

9:16

right, and not right.

9:18

So now we're in plain.

9:20

I'm more comfortable with dis orientation.

9:23

What you'll do, you'll also again mark

9:25

where your esophagus is.

9:26

Again, it's not something that you will not do without you,

9:29

you got your cusp views, you got the C arm orientation.

9:33

Remember you acquire each one of those,

9:35

you put the C-arm orientation and you'll label it for you.

9:39

And then you, you'll come here

9:40

and you'll give you the orientation for that.

9:43

It's in this annulus geometry where this is going to be

9:47

probably the most challenging component.

9:48

So in order to prepare for that, I usually like to zoom in

9:53

and we're gonna let, uh, terra recon kind of work its way

9:58

around identifying where, where this is now you're gonna see

10:02

that the machine is going, the AI is going

10:05

to have a little bit of a challenge orienting,

10:07

especially when you're using the, the, the metal

10:11

as your, as your border.

10:13

Usually what I do is once I have it lined up, I tend

10:16

to kinda mostly connect the dots

10:19

and try to stay in the middle of the rim, kind

10:22

of guide the orientation to ensure that I am as consistent

10:26

as I can be and

10:28

and maintain that annulus uh, dimension, right?

10:32

So essentially when we're looking at this,

10:34

you're looking at an annulus

10:37

of approximately 22 millimeters.

10:40

We know that from the carpentier mag valves.

10:43

Again, this is something that you can look up.

10:46

There are applications for this,

10:48

but in all reality is

10:49

what you really need is this average diameter

10:52

that's your annulus diameter average

10:54

and that's gonna be your best determinant of what kind

10:56

of valves you'll need for a 22 millimeter diameter derived

11:00

perimeter from uh, derived dia annulus

11:02

diameter of 22 millimeters.

11:04

We're looking at two types of valves.

11:06

If you're gonna do a sapiens valve,

11:08

you're usually looking at a valve of uh,

11:11

a sapiens valve number, uh, 23.

11:14

And if you're looking at a evolut pro valve

11:17

or an evolut effects, you're looking at a size 26

11:19

because if you know about those valves,

11:22

the mar maximum annulus diameter,

11:24

which would be this average diameter

11:26

and it tends to be anywhere between 22 and 23 millimeters.

11:30

And again, these are things that as you get more experience

11:33

with these valves, you'll you'll learn what these are.

11:36

The next step really is probably the hardest step in this

11:39

procedure and that has to do with the, uh, anatomy.

11:44

So you'll have terra recon give you these options for,

11:48

for different valves.

11:50

So you have the option to kinda modify

11:55

or use or assess.

11:58

My advice to you is to kinda either create a valve,

12:02

which I'm gonna show you how to do.

12:04

So the location we're gonna make a, uh, a sapiens valve,

12:10

the height of that valve is always 18 millimeters

12:13

for a 23 vessel diameter.

12:15

The diameter being a 23 valve is not really 23,

12:18

but it's an annulus maximum distance of 22 millimeters.

12:22

So we're gonna make this into 22 millimeters in dimension.

12:27

See, just like this, yeah,

12:31

so the part code which is name it three,

12:33

so you're gonna do 23 millimeter S3.

12:37

So now you're going to be able to label it right?

12:40

Once you've made it and adjusted you can do this

12:44

and it automatically knows to offset the annulus at 80%.

12:48

Meaning 80% of the valve is above the plane,

12:52

20% is right underneath the end, which is

12:55

what the manufacturer recommends for that.

12:57

So recon knows that and it's going to give you this option.

13:01

Now instead of 3D VR, you can do fluoroscope

13:04

and this is the one, uh, image that you have seen on,

13:09

on the, on the case stitching

13:12

file where it allows you to do that.

13:14

And I try not to encourage you to move this

13:16

because if you move it you will offset the annulus,

13:18

but if you do, don't be too concerned, right?

13:21

You're like, oh, I moved this, what do I do?

13:23

Now you can really come in here

13:26

and just set up this offset at 80%

13:28

and it'll allow you to, to maintain consistency in it

13:32

once you've had this valve embedded.

13:35

The next major measurement

13:37

that you're really interested in is going to be this

13:40

distance of this virtual valve to the left main,

13:44

which again you can see here as you're scrolling

13:48

how the stent of this valve see the top of it

13:53

is going to be at the level

13:55

or right above the left main osteum.

13:57

So if you put a valve in it

13:59

and you open the leaflets, that leaflet essentially is going

14:02

to create a covered stent.

14:03

So if you're going have a covered stent, you're going

14:05

to assume that all of this is going to be covered.

14:09

So you want to see if there's space

14:11

between the covered stent and origin of your coronary bowel.

14:16

And this is where we measured from here to the osteum

14:20

and get those measurements right.

14:22

In this particular case, the distance from the valve,

14:27

the sapiens valve to the OS

14:29

of the left lane ends up being 7.9 millimeters.

14:32

You come up to where you see the os

14:35

of the right coronary artery

14:36

and again you need to measure this

14:39

and it ends up being anywhere between like five

14:42

and it's a little bit here.

14:43

So it's about five millimeters, which is what I would done.

14:47

I would take a picture of each one of these and go.

14:50

Now if you look here at your model,

14:54

you'll see how this valve is not gonna come anywhere

14:57

to the OTT tubular junction.

14:59

You can also do this by verifying meaning I always like

15:03

to measure at the top of my uh, line

15:07

where is the last place where I see this.

15:09

And this is not in the cy tubular junction,

15:11

which is reassuring, meaning you look at all this gap

15:15

around it, there's plenty of space for you to be able

15:18

to allow blood flow to occur at any

15:20

point in the cardiac cycle.

15:21

Meaning you're not going to obstruct

15:23

the cynt tubular junction.

15:25

Now this is for this valve.

15:27

I would make the measurements

15:29

and all the other measurements, you know,

15:31

as we would coronary height, osteo height, et cetera,

15:34

the three views, et cetera.

15:36

Now once you finish that, you captured,

15:40

I would recommend you save the state so it save, save scene.

15:43

I would do uh, S3 valve

15:48

simulation, right?

15:50

That's how I would do this.

15:53

And then once you've saved that, remove the valve,

15:56

we're going to make an evolut.

15:58

And again, if you've made this, you can modify it.

16:01

So again, the location and height are different.

16:05

All evolut valves have a height meaning on the bottom

16:09

of the valve to where the top of that skirt,

16:11

where the valve is going to be.

16:14

Supra annular, it's always for older valves,

16:16

26 millimeters in height.

16:19

The valve itself to the top of it, not all

16:22

of it has valve itself tends to be 45 millimeters in length.

16:26

But the actual part that matters for this tends

16:28

to be 26 millimeters in height.

16:31

The inner di the diameter of this valve,

16:33

even though it's a 26 always is 23 millimeters.

16:38

And that's why we've selected this.

16:40

So I wanted to give you this example.

16:42

You can always change the shape to rigid tube, to tube,

16:46

et cetera, and they'll even let you change the color.

16:49

So if you're more like, I like my uh, my valve

16:53

yellow, so be it.

16:56

So see yellow valve

16:57

or purple, whatever color you would like, regardless

17:00

of the choice of valve that you had,

17:03

you cannot get back to the same thing.

17:06

The only thing that's different this time,

17:08

and you'll kind of assess this, is with this new valve,

17:12

there's really not a change in the distance.

17:15

See that? So it shouldn't really cost too much

17:18

of a change where you've had it.

17:19

'cause again, the valve is gonna simulate where it needs

17:21

to be, but what's going to be different is the height.

17:25

See how here in the previous valve we were

17:27

not at the san tubular junction.

17:29

Here you come all the way up

17:31

and you can see that there's definitely contact

17:33

with San tubular junction.

17:35

Now I would not be too worried about this valve not having

17:39

the ability or causing obstruction of the coronaries

17:42

because think about it this way,

17:44

well there's no contact here by the angulation of this.

17:48

There's really lots of space in nearly 75% of

17:53

that annulus, meaning blood will be able to get around

17:56

and more importantly, you'll be able

17:57

to get into the coronary sinuses to be able to fill the,

18:01

the valve or the coronaries in, in diastole.

18:06

Another measurement that oftentimes gets asked

18:09

for this valve is you see our plane here,

18:12

you're gonna create a line follows this,

18:16

and then you're going to follow this

18:21

to the angle of the root, right?

18:23

And this will be the angulation that is part

18:28

of the valve and more importantly whether this valve will be

18:33

flexible enough to be implanted into that.

18:37

So into this valve at this location, it's a step that we do

18:40

for the evolu valve that's important for you to know,

18:43

but it falls the direction of where this intersect is

18:46

and then where this intersect is located, right?

18:49

So it's 63 degrees, which again, it's not less than 40%,

18:52

but it's an angle that you need to be aware of

18:54

as we discussed during our our lecture series.

18:58

So again, once you have all this, my advice

19:02

to you is to save.

19:03

So I would save, uh, evolut

19:08

26 simulation

19:12

and then you'll be able to have this for your review

19:15

and assessment for what you need.

19:17

The rest of the, of the procedure, like we've mentioned,

19:20

is measuring the aortic root,

19:21

whether ejection fraction is certain level.

19:24

So most of that, you know,

19:26

we've dis we've discussed in other cases, but

19:28

because of the extent of this case by itself

19:31

and we have other cases, I don't wanna spend too much time

19:34

looking over at this particular case longer than

19:37

what we need to.