0:00

In this next video, we're gonna discuss TAVR complications,

0:03

and we can break down TAVR complications into two main groups.

0:07

Those that are procedural, they happen at the time of valve placement. Um,

0:12

and they can be both related to the valve placement itself and related to

0:16

vascular, uh, problems that happen in their during the procedure. Um,

0:20

and then the post-procedural complications. Um,

0:22

and the most common kind that we're gonna see there are halts I'll,

0:26

I'll explain that later and infection.

0:29

So what are the procedural valve related complications? Well,

0:33

there's quite a few. These, these are the most common listed here.

0:36

Annular rupture, uh, that's a big one. So, you know,

0:39

you place the device in the annulus ruptures.

0:41

The risk of this is increased in patients with lots of calcification of the

0:44

annulus valve migration.

0:46

So that means that you maybe don't have a great valve size.

0:49

So maybe the sizing went awry and your valve is perhaps a little bit too small,

0:53

um, for the, uh,

0:55

annulus and you actually place the valve and whoop it flies off higher

1:00

up into the aorta, um, heart block.

1:03

That's when the valve itself pushes on the conduction tissue and causes damage

1:08

leading to conduction system abnormalities. Coronary occlusion,

1:12

that's a dreaded complication, just like annular rupture.

1:16

That's where the device itself or the displaced valve leaflets cover up the

1:19

coronary osteo and cause compromised coronary blood flow.

1:23

This and annular rupture are the ones that can unfortunately result in patients,

1:27

uh, dying on the table during the procedure. Um, ascending aortic injury,

1:32

very rare, but you can get, um,

1:33

a dissection or something like that where the valve struts impact the ascending

1:38

aorta. And then stroke is another dreaded one. Um, you can imagine, you know,

1:43

moving a catheter around in the aorta and dealing with all those little bits of

1:47

calcification that are along the valve. Um,

1:50

and being displaced by the valve can put the patient at risk for emboli, uh,

1:54

from the valve itself causing stroke. So quickly about annular rupture,

1:59

uh, it's a rare complication. Less than 1% of tavr, uh,

2:03

the balloon expanded valves, um, have a higher risk, um,

2:06

because you can get a little bit more pressure against the aortic, the annulus.

2:10

And, um,

2:11

there's a higher risk if there's a small analyst and a calcified analyst.

2:15

And in particularly, we talked about L V O T calcifications in a previous video.

2:19

Um,

2:20

these calcifications and those under the non coronary cusp are associated with a

2:24

higher risk of, um, annular rupture.

2:26

So in these cases where ahead of time we see on the CT that there's a lot of

2:29

calcification, they may actually instead choose to go for a, um,

2:34

self-expanding valve,

2:35

which is maybe a little bit more gentle with the annulus and reduces the risk of

2:40

annular rupture. Uh, coronary occlusion we've talked about. Um,

2:44

you want to have coronary heights over 10 millimeters for safety and sinus

2:49

widths,

2:49

generally over 25 millimeters to minimize the risk of coronary occlusion,

2:54

heart block and paravalvular leak. Um, these are other complications that

2:58

Are both, are both associated with increased annular, L V O T calcifications.

3:02

So I'll refer you to the separate annular calcifications video where I talk

3:05

about those in more detail. What about the vascular risks? Um,

3:09

so vascular axis itself, we're putting these large catheters, uh,

3:13

usually from the femoral approach. Um, the risk is actually pretty low,

3:18

um, with the modern catheters. Uh, like I had mentioned, uh, in the, um,

3:22

devices, video, the devices over time have gotten smaller and smaller,

3:26

and the delivery systems have similarly gotten smaller and smaller,

3:30

so the vascular risks have reduced, uh, accordingly.

3:35

Um, early on in the, um, TAVR experience, the rest was actually quite high.

3:40

2020 5% of patients had some sort of important vascular complication. Um,

3:44

but now it's, uh, considerably lower.

3:47

And this is just showing a patient with very large pseudo aneurysms, uh, from,

3:51

uh, catheter placement.

3:54

Other complications besides pseudo aneurysms.

3:57

You could also see dissection rupture, uh,

4:00

hematoma or distal embolization. And, um,

4:03

the key determinants of vascular access risk are vessel diameter and calcium

4:07

burden. Um, and those are associated with higher risk of complications.

4:11

So you can imagine a small,

4:12

really stiff vessel doesn't accommodate the sheath very well, um,

4:16

and so has a higher risk of complications. Changing gears here,

4:20

what about the post-procedural complications?

4:23

And first I wanna talk about halt hypo attenuating leaflet thickening.

4:28

Um,

4:28

this is a entity that was discovered somewhat recently,

4:33

um, in the history of tavr. Um,

4:36

they were performing some post TAVR CT scans and noticed this entity along the

4:40

valve leaflets. I'll show you what it looks like. Um,

4:43

basically what happens is you get thrombus along the valve leaflets.

4:47

It has an unknown impact on valve durability. Um,

4:50

we see it in roughly 10 to 20% of patients. So it's actually quite common. Uh,

4:55

oftentimes these patients will have increased gradients, meaning higher, uh,

4:59

gradient across the aortic valve because of restricted valve motion. Um,

5:02

the patients may or may not be symptomatic. Um, if you see it,

5:06

it can be treated by anticoagulation,

5:08

tends to resolve when we see a hypo attenuating leaflet,

5:13

thickening or halt. We wanna do two things. We wanna report the degree of halt,

5:17

and that's how much of the cusp is filled with thrombus. So this is a,

5:20

a figure here showing, um, an illustration of what that halt looks like. Um,

5:25

so this, imagine this is the cusp,

5:28

the halt is some thrombus that just basically looks like this low attenuation

5:32

stuff that kind of just fills in the cusp on the aortic side of the valve.

5:37

And we can report the amount of halt roughly, you know,

5:40

qualitatively the amount of, um, the cusp is filled with thrombus, um, as so as,

5:45

uh, depicted here.

5:46

And then the other thing that we wanna look at is the severity of restricted

5:51

leaflet motion. Um, so when you have this, um, uh,

5:54

hypo attenuating leaflet thickening,

5:57

Um, which you see here, this is a short axis view,

5:59

you can see the thrombus sitting in the aortic valve cusp.

6:04

So what that does is in systole,

6:06

you'll actually find that the leaflets don't open entirely,

6:09

and when they don't open entirely, um, you end up with, uh,

6:13

restricted motion and you can measure that restricted motion in systole by

6:17

basically taking the, um, percentage of restriction, uh, according to, um,

6:22

the, uh, radius of the actual, um, valve, uh, itself. So that's what this,

6:27

um, graph is showing us. So basically,

6:29

if you have 50 to 70% restrictions considered moderate, severe, over 70%,

6:34

and then a hundred percent is a mobile.

6:37

So when we're seeing patients who have this halt, we wanna report, um,

6:41

both of these different metrics and I'll refer you to this really nice review

6:45

article here, which is from, uh, where I grab this, uh, figure, um,

6:50

and does a really nice job of explaining the whole concept of halt and,

6:53

and showing it in some great images.