0:00

So today I'm gonna talk about the importance of aortic stenosis and how that

0:03

relates to the TAVR device. So, aortic stenosis is a very common disease.

0:08

It affects approximately 5% of the population,

0:10

and mostly these are elderly patients, 70 years or older. Uh,

0:14

once symptomatic aortic stenosis is a deadly disease and it results in death

0:18

over 50% of patients at two years if untreated. Um, so obviously it's,

0:23

it becomes very important to, to get these patients treated. Um,

0:26

and treatment previously had been surgical aortic valve replacement. However,

0:31

in the past, say, 10 to 15 years,

0:33

transcatheter aortic valve replacement or TAVR is becoming more widely used.

0:38

And just the cine image on the left just shows a patient with severe AOR

0:42

stenosis. You can see that this cusp here, which is severely calcified,

0:46

is not moving very well, uh, throughout the cardiac cycle. And that's, uh,

0:50

pretty typical for patients with aortic stenosis. So this is a really classic,

0:55

um, uh,

0:56

graph that you'll see a lot if you look into the AIC stenosis literature.

1:00

And it's from, uh, quite a while ago, a publication back in 1998. Um,

1:05

and it shows up in all the textbooks as well. And,

1:07

and basically what this shows is that, um,

1:10

for patients with severe AIC stenosis, um, as their age increases, um,

1:14

and, uh, the,

1:16

the percent survival is quite high up until the point where patients get

1:20

symptoms. Once patients become symptomatic,

1:22

then all of a sudden the mortality goes way high and patients, um,

1:26

basically drop off a cliff in terms of mortality. Um, and that's what, um,

1:30

mentioned on the previous slide that the, there's a really high, uh,

1:34

rate of mortality once symptoms start. Um, like I said,

1:37

approximately 50% within two years. Um,

1:39

so this really underlines the fact that these patients really need to be

1:42

treated, uh, once symptoms start. Well,

1:46

what are the metrics to decide on the severity of AIC stenosis? Um, well,

1:50

transthoracic doppler echocardiography is the mainstay of diagnosis,

1:54

and there are three different measures that are typically looked at. Uh,

1:57

aortic valve area peak aortic valve velocity,

2:00

and transaortic pressure gradient. And these can all be measured, um,

2:04

using doppler echocardiography.

2:06

And you can see here the metrics that are used to decide whether or not somebody

2:08

has severe air stenosis. Um, and so in the setting of tavr,

2:13

basically all of the indications for TAVR to date, um, are for patients, uh,

2:17

with severe aortic stenosis. Um,

2:20

now I'll talk a little bit later about some work that's being done to look at

2:23

moderate aortic stenosis patients, but, um, as of, uh,

2:26

the time of this video at least, um,

2:27

the indications for tavr all for patients with severe as, uh,

2:32

and this is what it looks like on ct, um, a normal patient on the left,

2:36

and then a patient with severe IX stenosis on the right,

2:38

you can see that the valve opening, um,

2:40

here in cyst is much smaller in area than that, um,

2:44

which we see on the normal patient. Um,

2:46

and generally what we talked about based on that previous side, as you remember,

2:50

um, is an, uh, valve opening area,

2:52

less than one centimeter squared is gonna be in the category of severe stenosis.

2:57

So I wanna talk

2:58

A little bit about the history behind TAVR and how it became more and more

3:02

widely used, uh, like it is today. And,

3:05

and basically the story of TAVR is this story of multiple, uh,

3:09

randomized clinical trials, uh,

3:11

over a long period of time that went from patients that were very,

3:15

very high risk, and that early clinical trials,

3:17

those are the ones in red partner one B, partner one A, and CoreValve.

3:21

These are really sick patients with high, um, s t s scores.

3:25

The s t s scores are really this, um, it's a surgical, um, score, uh,

3:30

that's used to determine how risky a patient is for surgery. Um,

3:34

and they're various calculators online that can give you the s t s score,

3:37

but it's based on various, uh, comorbidities for the patient.

3:40

The higher the score, the more risky the surgery. So, um, as, uh,

3:44

the TAVR device, uh, was rolled out, um,

3:47

more and more clinical trials were done first in patients with very high s t s

3:51

scores or high risk. Uh, and then as time went on,

3:54

they moved into intermediate risk patients and low risk patients.

3:58

Those are those green, uh, and yellow bars here. And so you can see today, um,

4:03

here in, you know, the early, uh, 2020s, um, we have, uh,

4:07

established that TAVR is useful in all of high intermediate and low risk

4:11

surgical risk patients. Um,

4:13

and this is just an excerpt from a recent publication, um,

4:17

a guideline on update on indications for tavr, uh, based on the recent,

4:22

um, American Heart and, uh,

4:24

American College of Cardiology guidelines for management of heart disease. Um,

4:28

and they said that the continued evolution of transcatheter valve implantation

4:32

technology and the result of multiple trials have firmly established this

4:36

approach as an alternative to surgical aortic valve replacement in all risk

4:39

groups. And that's the important thing. So, um, now TAVR is,

4:43

is indicated for all patients, whether they be high risk or low risk.

4:47

This is a summary of these, uh, indications, uh,

4:51

for TAVR from this most recent guideline. Um,

4:54

and you can see here that the level of evidence is high for, uh,

4:58

the top indications and not as high as possible,

5:01

but in the intermediate range for those middle indications.

5:03

And I'm not gonna read these out,

5:05

but basically this summary is for older patients. Um,

5:09

TAVR is preferred, um, for symptomatic older patients, greater than 80, um,

5:14

and a life expectancy more than 10 years. And then, um,

5:17

you can choose between surgical aortic valve replacement or tavr, um,

5:21

in patients with symptoms and who are at age 60 to five to 80. Um,

5:25

and then there's,

5:25

there's more details here that you're certainly free to look up on your own.

5:29

Just to note the words. TAVR and TAVI are used interchangeably, uh,

5:33

in the literature. Um, you'll find both, uh, written. So in this case,

5:37

obviously you see, you see tavi and there's no difference between the two.