0:00

Okay, so the next, uh, exam here, uh,

0:03

is in an 82-year-old, which ought

0:05

to get your guard up right away because it's high risk.

0:08

The reason that this patient underwent a coronary CT is he

0:12

was pre-procedure for a pulmonary vein isolation,

0:15

which can cause tachycardia on mass ischemia.

0:17

And I believe the pre, uh, CT planning, um, was suggestive

0:22

of atherosclerosis.

0:24

It, um, note was made that there's pretty extensive, um,

0:28

calcifications in all the vessels.

0:30

And, uh, ct uh, calcium scoring is part of our exam here,

0:34

confirms that it's like a rock.

0:36

Now, I don't want to confuse the, um,

0:39

mitral annular calcification for that.

0:42

Very easy when you have the CT angiogram.

0:44

Um, but this is within the myocardium at the edge

0:47

of the valve, so a benign form of calcium.

0:50

Let's now go further and do the CTA,

0:53

and I'll just move somewhat quickly on this case

0:55

because you can see it's not gonna be easy,

0:58

but I'm already just on axials, that's a severe stenosis.

1:01

I'll confirm it. Uh,

1:02

but there's pretty much not a lot else I'm gonna be able

1:06

to conclude other than, uh,

1:08

maybe I could downgrade this part that's noncalcified

1:10

to moderate, but some really dense calcium there.

1:13

Uh, you have to assume the worst too.

1:15

Um, we're, the goal here is to clear, so

1:17

that's either two moderates or a severe

1:19

and a moderate enough to say that already

1:22

has granted a ticket to the cath lab.

1:24

Uh, but we want to be as accurate as we can.

1:26

If you're a pessimist, um, you have 18 coronary segments

1:30

and 18 chances to be proven wrong.

1:31

If you're an optimist, you have a per patient level, um,

1:35

positive predictive value that should be

1:36

fulfilled just by that one vessel.

1:38

And you'll see that in any published study.

1:41

If you look on a per patient basis, CT performs really well,

1:43

but the more complex the disease, the more likelihood

1:45

of mild discrepancies or, you know, discrepant vessels.

1:48

And we've seen a couple of those already.

1:51

Let's just note that there is plaque in the left main

1:54

and on the long axis, I don't believe it's significant,

1:57

but right at that distal left main

1:58

where it's already bifurcated,

2:00

things are getting already kind of hairy.

2:02

I see that there is a fair amount

2:07

of really densely calcified plaque.

2:10

It could be severe, um, almost certain severe.

2:13

It also extends in the diag.

2:14

So I'm, if you're counting,

2:16

I've got moderate versus severe mid RCA two lesions,

2:19

I've got at least moderate prox, LED.

2:22

Uh, a lot of, uh, cardiologists will treat proximal LED

2:25

with a little more tender care, uh,

2:27

because there's so much

2:27

myocardium or risk, we have that here.

2:29

So moderate, maybe severe at the calcified site.

2:32

Proximal, um, first diagonal more disease in the LED.

2:37

Uh, the vessel gets small, harder to say there.

2:40

Uh, and then I'm gonna just check the circumflex really

2:43

quickly, but this patient needs to go to the cal.

2:45

Oh yeah, there's a severe right there.

2:46

You can have a hard time distinguishing severe

2:49

versus occlusion.

2:50

And we talked a bit about this in the lecture,

2:52

and I think the last case

2:53

of the stent illustrated the difficulty

2:55

of seeing a hairline lumen.

2:57

This is gonna be either subtotal

2:59

Or total occlusion.

3:00

Um, but now I'm gonna use my heuristic here.

3:03

So we know in native vessels, especially things less than

3:06

between nine and 15 millimeters tend to be, um, severe

3:10

stenosis that are tight rather than like a subtotal rather

3:13

than an occlusion kind of on that border here.

3:15

So I'm gonna favor a subtotal occlusion of that circumflex,

3:18

but really it's gonna come down to

3:20

what the catheterize sees.

3:21

Non-dominant vessel. So there's that.

3:23

I also see some lateral wall thinning.

3:25

So my guard is up that there's been an ischemic

3:27

insult, uh, already.

3:29

Uh, I don't even, this is a systolic frame, just one.

3:31

But I have wall thinning and a little bit

3:33

of fatty metaplasia there.

3:35

So that hypodensity.

3:37

But since I have it, I might

3:38

as well look at the complete cardiac cycle.

3:40

I think I would call this hypokinesis

3:42

of the mid tu papillary muscles.

3:44

So mid lateral wall,

3:45

so probably a circumflex territory infarct,

3:48

which shouldn't be a shock.

3:49

Um, and then just looking at the rest of it, you have, uh,

3:53

pretty good function.

3:55

Remember these are resting cts,

3:56

so we're not, it's not a stress test.

3:57

It's uh, so if you already have a wall motion abnormality,

4:00

it's usually due to a really severe or occluded disease.

4:03

Let's move on and let's see what happened.

4:05

Clinically needed to do the procedure, so they wanted

4:08

to check the coronaries.

4:11

High pretest risk, really a hundred percent risk.

4:13

Now it's, there's no way the CT is gonna miss, uh,

4:15

on all those vessels.

4:16

So let's look at that cath left main patent

4:20

occlusion on the circumflex.

4:21

All right, so the, uh, we were in the border zone,

4:23

so we could go either way between nine and 15 millimeters.

4:26

And here's your LAD kind of tortuous coronaries

4:30

and I think I was worried really the prox.

4:32

Oh yeah, kind of tubular. Um, and that diagonal.

4:35

So I think this is confirmatory really nice correlation.

4:38

Let's move on to the RCA boom goes the dynamite.

4:42

So I have at least a moderate right there.

4:44

I'm gonna look again here.

4:46

Yeah, it's kind of middling stenosis.

4:49

You can see they went and they, they decided to treat

4:52

that no more culprit lesion, the LAD,

4:53

they left the RCA alone.

4:55

Uh, I'll read you off what the expert, uh,

4:58

interventionalist said left main 10 to 20% LAD,

5:02

heavily calcified diffuse 60% stenosis large OTE D one 70

5:06

to 80%, uh, circumflex proximal CTO

5:10

as we talked about chronic total occlusion,

5:12

which really you'd have to know by history.

5:14

It was chronic, um, with left to left

5:16

and right to left collaterals.

5:18

I'll go back and show you that.

5:19

And then the, uh, RCA, the thought on osce 80 to 90%

5:22

and then mid vessel 50%.

5:24

They also noted something that you'll see in catheter,

5:27

and I hope you read the

5:28

catheter reports on the studies you do.

5:29

They said there was severe wave form dampening

5:32

with engagement, meaning when they put the catheter in,

5:34

they always have a pressure transducer

5:36

and that was occlusive to the vessel.

5:38

So they knew there was an osteo lesion.

5:40

I wanna first look at my RCA again.

5:42

Um, in fact, I'll just show you the, uh, curve planer.

5:44

Uh, so I think I just glossed right through

5:46

that calcified plaque there when I got distracted

5:49

by the more distal but calcified plaque can very closely

5:52

overlap the density of contrast.

5:54

Let's go back and look at this. Oh yeah, so I

5:56

Just think I must have scrolled right through that.

5:58

So a tight stenosis in the osteum

6:01

and then a second one here.

6:02

Back to the cath. Just since we have it,

6:05

I wanna look at this left

6:06

and find a, if a catheterization is done carefully,

6:09

what will happen is they'll lay on the fluoroscopy

6:13

long enough after the injection

6:15

to see collaterals in this view.

6:18

We can see that there is that circa occlusion.

6:21

I don't see a ton of left to left collaterals,

6:23

but if you, um, let's stay on this one for a moment.

6:26

We know that the vessel occludes right here.

6:28

So if we see something fill in in this area late

6:31

and we do, that means there's left to left collaterals.

6:35

No, no contrast was injected on the right.

6:37

Now let's flip to our RCA injection.

6:40

So yeah, you can see that tight stenosis there.

6:42

If we pay attention over here

6:44

and they stay, there's that dense calcification in the, uh,

6:46

LAD uh, circumflex maybe.

6:48

Um, so somewhere around here

6:50

there might be late opacification of collaterals.

6:54

There it is. So there's these tiny

6:55

collaterals through the AV groove.

6:58

Um, there can be tiny collaterals with the septum

7:00

and along and here's some as well.

7:02

So that might be the distal circumflex

7:04

right off at the edge of the screen.

7:05

And a careful cath done with a really long extra,

7:09

uh, fluoroscopy.

7:10

We'll start to reveal those.

7:11

And that's important to note

7:12

because you know, you might have a myocardial perfusion

7:14

study that's abnormal without infarct.

7:16

And that's why in the bench labs,

7:19

if you tie off a dog's LED collateral start

7:22

to form within 30 minutes or appear,

7:23

they're probably there and just open up.

7:25

Uh, and so one of the treatments

7:27

for angina is nitroglycerin.

7:30

Nitrates dilate the vessel.

7:32

So you open up these small collaterals and,

7:33

and that's a way to treat and medically manage

7:35

before you, uh, have to stent anything

7:37

and treating vessels that are too small to stent.

7:40

So a nice case with a pitfall lesion in the proximal right

7:43

coronary artery as well as

7:46

distracting is additional disease.

7:47

And then a really, um, difficult

7:51

to ascertain chronic total occlusion here of the, uh,

7:53

circumflex, which was confirmed angiographically just

7:58

for completeness and to talk about pretest wrist.

8:01

This patient's calcium score was 4,165.

8:06

I think that was a successful CTAI wouldn't block it.

8:09

The other thing is calcium scoring only applies percentile

8:13

wise to asymptomatic people, um, of like age, gender,

8:18

ethnicity, race, who are free

8:20

of known clinical cardiovascular disease and diabetes.

8:23

I don't know if any of those other caveats applied here.

8:26

Um, it's hard to decide whether this is really the use in a

8:29

symptomatic patient or a pretest just

8:30

'cause we knew we had to do a, an

8:32

atrial fibrillation treatment.

8:33

But I think the important thing

8:34

to remember is the calcium score is really just

8:36

to make sure we don't miss things.

8:37

It's not gonna be used to decide whether to proceed

8:40

with the CT and it's not gonna be used to, uh,

8:42

give somebody a percentile score versus peers,

8:45

because we have the angiographic anatomy here.