0:01

Let's transition to pseudoaneurysm complications.

0:05

So let's look at this 51-year-old gentleman.

0:07

HCV, decompensated cirrhosis,

0:09

hepatic encephalopathy.

0:10

He presents post-operative day one after having

0:13

a successful transarterial chemoembolization.

0:16

So you receive a call this morning

0:17

because the patient started to have

0:19

worsening groin pain and swelling.

0:22

So bedside ultrasound is unable to

0:23

adequately visualize the area, and so CT

0:26

scan reveals the following imaging findings.

0:28

What do we see?

0:30

A little bit of an ugly little fella, huh?

0:33

What's this imaging finding?

0:34

What would you call this?

0:36

Well, I suppose we would call

0:38

this a pseudoaneurysm, which is

0:39

actually a contained rupture.

0:41

Hence the contained rupture here,

0:43

hence the parent vessel here.

0:46

This is our little tiny neck, which for us

0:47

is a good thing for a variety of reasons.

0:50

So the pseudoaneurysm is a communication from

0:53

the feeding artery through this narrow neck.

0:55

So, when we talk about a pseudoaneurysm,

0:58

we're talking about a false

0:59

aneurysm, a contained rupture.

1:01

One that is not contained by the typical

1:03

three layers of the arterial wall.

1:06

Namely, the intima, media, and adventitia.

1:09

There's a violation of one or two layers.

1:12

With only an overlying one or two layers in place,

1:16

either the media and the adventitia or the adventitia only.

1:20

They can take this configuration, which is

1:22

called ular, the sort of fusiform dilation.

1:26

But a pseudoaneurysm is a pseudoaneurysm is a

1:28

pseudonym, which is in fact a contained rupture.

1:31

So when we sort of see patients that present

1:33

with these, we want to consider sort of the

1:35

findings of pain, swelling, and pulsatility.

1:39

You know, with or without the

1:41

presence of a thrill or murmur.

1:44

They occur in about 0.05

1:45

percent of cases to about half a percent

1:49

of all patients undergoing percutaneous

1:51

arterial or coronary catheterizations.

1:54

And particularly low incidence, you know,

1:55

but when they occur, these ranges can

1:58

result in pretty significant morbidity.

2:00

So, the sources of trauma include if someone,

2:04

like in the previous case that we looked at, you

2:06

know, with sort of rupture, a barren vascular

2:08

access, that can provoke a pseudoaneurysm.

2:11

Projectile injuries, bullets, bird

2:14

shot, things of that nature, again,

2:16

can damage the vessel and cause it to sort of

2:18

develop these outpouchings, stabbings, surgical

2:21

embolectomies, passing a Fogarty catheter.

2:24

An example of a bypass graft, you can get

2:26

a sort of tibial aneurysm, pseudoaneurysm

2:28

in that particular case, certainly.

2:30

So it's something that you want to sort

2:31

of keep in mind in terms of trauma.

2:33

So what are some risk factors

2:34

of arterial pseudoaneurysms?

2:36

Well, you know, if you have a low femoral

2:39

arterial puncture site, this is something

2:41

whereby you are trying to compress and

2:44

you don't really have that backstop, that

2:46

femoral head to allow you to sort of achieve

2:49

hemostasis by compressing the vessel against it.

2:52

You know, depending on sort of the girth of the

2:54

individual, the soft tissues may give with the

2:56

vessel and now you're bleeding sort of in the

2:58

site and you're getting a contained rupture there.

3:00

Larger sheath, grade 6 French,

3:01

can increase that risk.

3:02

Anticoagulation, indeed, as well.

3:05

But also antifibrinolytic

3:07

therapy, thrombolytic therapy.

3:09

As well, and just older individuals because

3:11

of sort of laxity and just the, the

3:14

sort of makeup and collagen within

3:16

the actual wall, that sort of can

3:19

actually precipitate pseudoaneurysm formation.

3:22

Arterial hypertension, really, it's no

3:24

surprise why this is the cause of sort of

3:27

pseudoaneurysm or contained rupture formation.

3:29

And of course severe calcification

3:31

just complicates the access.

3:33

So what does a pseudoaneurysm

3:34

actually look like on ultrasound?

3:36

Um, so it has a beautiful appearance.

3:40

And this is sort of the appearance

3:42

that it has, which is essentially.

3:45

This appearance whereby you have almost like

3:47

a little yin and yang sort of effect, okay?

3:50

When you see the color Doppler, you get this

3:52

bidirectional, turbulent, swirling blood flow.

3:55

That’s the so-called yin and yang sign.

3:57

If you are just using grayscale, you can

4:00

also see this sort of rounded anechoic

4:03

sacculation, if that’s what it is, or a

4:05

fusiform configuration, if that’s what it is.

4:08

And you may or may not have intraluminal thrombus,

4:12

but it’s good to sort of suspect that as well.

4:14

So how do you manage a pseudoaneurysm?

4:16

Well, observation.

4:18

If it’s less than three centimeters in

4:19

size, you know, rumor has it they improve.

4:22

And I would say that rumor is, uh, correct.

4:25

You can observe these and they just

4:27

resorb and thrombose on their own.

4:29

Thrombose, as opposed to resorb.

4:31

Ultrasound-guided thrombin injection

4:33

is actually often the first-line

4:35

treatment for ones that are iatrogenic.

4:37

Alright, it takes control of the situation.

4:39

You know, but there is a little

4:40

sort of point about that.

4:42

And that really has to do with the fact that

4:44

the neck of the pseudoaneurysm needs to

4:46

have sort of a particular configuration.

4:49

Okay.

4:49

It can’t be too wide.

4:51

You often sort of consider sort of two

4:52

millimeters greater than two millimeters

4:54

sort of being one of those numbers that

4:57

people just sort of recognize as being if it’s

4:59

wider than that, then they may not consider it

5:01

because of the risk for non-target embolization

5:04

of the thrombin into the parent vessel.

5:07

Some people also consider the ratio of

5:09

the neck to the pseudoaneurysm as also

5:11

being something that should be considered.

5:13

The third thing that you want to sort

5:14

of think about when it comes to sort of

5:15

management is ultrasound-guided compression.

5:17

Placing an actual probe and watching it

5:19

as you compress it and actually collapse

5:22

the, uh, the pseudoaneurysm and only

5:24

visualize the flow in the parent vessel.

5:26

You know, we can do that, you know,

5:27

and actually see the effect of

5:29

the compression and ultimately sort

5:31

of see the thrombosis that results.

5:34

Stent graft exclusion can also result in

5:36

that, where you just literally obliterate

5:38

the flow into that container option.

5:40

Of course, surgical repair is something

5:42

that you also want to consider.

5:44

So, how do you perform

5:45

percutaneous thrombin injection?

5:46

It's funny you should ask.

5:47

Well, the question here is, we

5:49

want to direct the needle away from the

5:52

neck, which is the conduit now from the

5:55

pseudoaneurysm to the parent vessel.

5:57

We don't want any of that thrombin, that

5:59

prothrombogenic, that procoagulant thrombogenic

6:02

material to enter the parent vessel and embolize,

6:04

in the case of the common thrombectomy, you know,

6:06

to the lower extremity, the leg, and the foot.

6:09

And so what we're going to do is direct this away.

6:11

And so we use little aliquots, 500 to 2,

6:14

000 units of thrombin being sort of the

6:16

goal, using a nice 21 and 22 gauge needle.

6:20

For us, this often really gets the job

6:22

done when we're sort of doing this very

6:23

clearly, cleanly under ultrasound guidance.

6:26

So, what are the contraindications

6:27

to percutaneous thrombin injection?

6:29

You know, if there's a large neck diameter,

6:30

as I mentioned, greater than a

6:31

centimeter, rather, is sort of, you know,

6:33

considered to be particularly large.

6:36

And so we don't want to consider that

6:38

for a patient that warrants thrombin, uh,

6:41

management, a percutaneous thrombin injection

6:42

for management of the pseudoaneurysm.

6:44

If the patient has any anaphylaxis to

6:46

bovine products, think again, can't use

6:50

thrombin in that particular setting,

6:52

given that it's a bovine derivative.

6:54

And if the patient has an infected

6:55

pseudoaneurysm, the deal's off.

6:57

We won't be injecting thrombin because

6:59

that will be a foreign substance that

7:00

could then now become super infected.

7:02

So, pre-thrombin injection, here we see the

7:05

nice yin and yang flow from the parent vessel.

7:09

And post-thrombin injection, now you see it, now

7:12

you don’t. So, what I want to really sort of understand

7:16

here is, when you think about sort of percutaneous

7:19

versus open repair, is there a consideration?

7:21

Well, there is.

7:22

So, I want you to evaluate the exact entry into

7:25

the pseudoaneurysm and the outflow distal to it.

7:28

You know, when you're sort of considering

7:29

percutaneous embolization or stenting, you

7:31

know, these can be therapeutic if there's

7:33

not a significant outflow contribution or

7:35

if there are distal feeding collaterals.

7:37

The technique really involves distal followed by

7:40

proximal embolization across the pseudoaneurysm.

7:43

An open repair actually should be

7:45

considered if there's a significant

7:46

contribution to the extremity.

7:48

In which case, to our surgeons, our vascular

7:51

colleagues, very much appreciate their support.182 00:06:44,730 --> 00:06:46,410 If the patient has any anaphylaxis to

6:46

bovine products, think again, can't use

6:50

thrombin in that particular setting,

6:52

given that it's a bovine derivative.

6:54

And if the patient has an infected

6:55

pseudoaneurysm, the deal's off.

6:57

We won't be injecting thrombin because

6:59

that will be a foreign substance that

7:00

could then now become super infected.

7:02

So, pre-thrombin injection, here we see the

7:05

nice yin and yang flow from the parent vessel.

7:09

And post-thrombin injection, now you see it, now

7:12

you don’t. So, what I want to really sort of understand

7:16

here is, when you think about sort of percutaneous

7:19

versus open repair, is there a consideration?

7:21

Well, there is.

7:22

So, I want you to evaluate the exact entry into

7:25

the pseudoaneurysm and the outflow distal to it.

7:28

You know, when you're sort of considering

7:29

percutaneous embolization or stenting, you

7:31

know, these can be therapeutic if there's

7:33

not a significant outflow contribution or

7:35

if there are distal feeding collaterals.

7:37

The technique really involves distal followed by

7:40

proximal embolization across the pseudoaneurysm.

7:43

An open repair actually should be

7:45

considered if there's a significant

7:46

contribution to the extremity.

7:48

In which case, to our surgeons, our vascular

7:51

colleagues, very much appreciate their support.