Peripheral aneurysms: How this silent threat is found and treated

Transcript

Caitlin Whyte (Host): This is Flourish. I’m Caitlin Whyte. With me is Dr. Joseph Blas, a vascular surgeon from Prisma Health. Today we will dive into peripheral aneurysms, how they develop and how they are treated.

Well, Doctor, welcome to the show. My first question for you is, can aneurysms occur in places other than the brain?

Joseph Vincent Valenti Blas, MD: Yeah, so that’s a very good opening question. The reality is that people hear aneurysms and they automatically think brain or aorta. But what they don’t realize is that these aneurysms can actually develop quite frequently in the arms and legs. And when they declare themselves, oftentimes it’s an emergency. So it’s less well-known, but not less dangerous.

Host: And what does peripheral aneurysm mean?

Joseph Vincent Valenti Blas, MD: A peripheral is an overarching term that delineates anything that is outside the central system like the brain and the aorta. It starts mostly in the iliacs and can go into any other part of the appendage, so your arms or your legs, and that’s what we would call peripheral artery aneurysms.

Host: Gotcha. Thank you for that. Well, on that note, where in the body are these aneurysms more likely to develop and why?

Joseph Vincent Valenti Blas, MD: I think it’s worth noting that in order to understand a little bit of this pathophysiology, you need to understand what an aneurysm is. An aneurysm in just a plain language description is a localized dilation of an artery.

These things can occur in any one of your four extremities, behind your knees, those called the popliteal artery. In your groins, those are called the common femoral, the superficial femoral or the profunda femoral, the deep femoral artery. In the arms, it can be an axillary or a subclavian artery aneurysm, or even further down the arm where the artery becomes a little smaller, we call that the brachial artery, and so they can occur there as well.

Host: Well, let’s also talk about who is most at-risk for developing these peripheral aneurysms. Are there any health conditions or lifestyle factors involved?

Joseph Vincent Valenti Blas, MD: Yeah. Actually, one of the ways that we can uncover these aneurysms is by a vigorous screening program, and part of that is knowing who’s at risk for these aneurysms. And we have very well-defined high-risk groups for people with aneurysmal disease, such as older men, anyone with a smoking history or tobacco use at all.

People with an established history of atherosclerosis. And in layman’s term we call that hardening of the arteries. If you have an aneurysm in one area of your body, it is very likely that you have a higher propensity for an aneurysm in another part of your arteries or another area of your body. We would screen those people accordingly.

And then there are some more unusual type of aneurysms that occur because of previous interventions, like vascular type interventions like an arteriogram or somebody who had an, a heart cath, a cardiac cath that went through the artery wall. Those kinds of aneurysms, we would call pseudo aneurysms.

But those are also aneurysms that we would need to pay attention to.

Host: Great. Well, you mentioned screening is important when it comes to uncovering these aneurysms, but how otherwise are they diagnosed? Are there symptoms that people should watch out for?

Joseph Vincent Valenti Blas, MD: Really the overarching theme is that the diagnosis for aneurysms is pretty straightforward. The challenge, however, is thinking to look for them. These aneurysms don’t cause symptoms unless they have already become complicated, meaning they have caused one of the complications of an aneurysm that we know exist.

I can certainly go through that list if that might be helpful.

Host: Sure. I’d love to hear a few.

Joseph Vincent Valenti Blas, MD: Yeah. So, aneurysms behave in a relatively predictable pattern. Aneurysms grow, and within that growth, the aneurysm can do usually one of four things. An aneurysm can grow to the point where the wall of the aneurysm becomes thin and can rupture.

So, it can have a break in the integrity of the wall, and then the blood that is usually housed within the artery can exit the artery into the surrounding tissues. And that can be not only a limb threatening problem as in the case of peripheral artery aneurysms, but it can be a life-threatening problem, obviously with the blood loss entailed in that.

A second thing an aneurysm can do is that it can embolize. Embolize is a term that we use for when something inside the artery breaks off and travels, lodging in a distal part or a further downstream part of the artery, and it may block blood flow to a critical organ or to the foot or the hand.

The reason that that happens is because as the aneurysm grows, the clot on the inside of the aneurysm builds up. With every heartbeat, your body is exerting pressure, a shearing pressure that may cause the clot that’s building up inside the aneurysm to break off and go downstream. A third thing is that it can compress other structures, and if aneurysms get large, this is a particular risk in the popliteal artery aneurysms.

If aneurysms get large enough, they can take up space and things that lie adjacent to arteries are found everywhere in the body. And those two things are namely veins and nerves. And so, if an aneurysm, say for instance, the popliteal artery were to get large enough, it could compress the vein and cause a deep vein clot or thrombosis. Or it could compress the nerve and cause symptoms associated with nerve compression, paresthesias, numbness, neuropathy and that sort of thing.

Then there are more unusual behavior patterns, but well documented, where they can fistulize. Fistulize is a term that we use to denote a communication between two structures that isn’t normally there. You can think of it as a more controlled rupture, if you will.

If it ruptured into an adjacent organ or adjacent vein, that connection can cause symptoms of swelling, as in the case of a vein or organ failure as in the case of rupturing and fistulizing. Those are in general the behavior patterns for these aneurysms and the aneurysms behave in one of these manners, sometimes they have the ability to behave in more than one of these manners, depending on the location of the aneurysm in the peripheral system.

The other behavior pattern that an aneurysm can have is called thrombosis. And that basically means that the amount of clot inside the aneurysm has grown to the degree that it can shut off that artery acutely. Thrombosis denotes acute cessation of blood flow through that artery, usually from blood clot.

When that happens, obviously the organ on the other side of that aneurysm of that artery has only a limited amount of time before it will start to have irreversible signs of ischemia or lack of blood flow.

Host: What treatment options exist for these aneurysms located outside of the head, and how are they different from brain aneurysm treatments?

Joseph Vincent Valenti Blas, MD: There’s not a one-size-fits-all remedy for these aneurysms. There’s a lot of decision-making that goes into how we fix them. Now, with technology and as the field has progressed, we have gotten many more tools at our disposal to treat these aneurysms. We can do something as simple as observing an aneurysm. That management strategy is done for aneurysms that are too small to fix.

There’s still an aneurysm. They have not gotten to the size yet where we would be concerned based on historical literature that they would rupture or they don’t have clot inside them or previous evidence of it being embolic in nature that we can reasonably survey or observe those aneurysms.

Another mode of treatment is the open surgical arm. That’s where we actually do bonafide surgery. So we actually open the skin, we go find these aneurysms and to fix it, we can do what what’s called an interposition graft, which means that we open the aneurysm and we typically do a bypass right in the line of the aneurysm.

Or we can do a bypass around the aneurysm and then tie off the aneurysm above and below to prevent one of those complications that we listed earlier from happening. A much more common way of treating aneurysms nowadays is the endovascular strategy. So endovascular denotes the ability to treat a pathology, anything including aneurysms, endovascularly. So, from within the vascular system, that’s what that word means.

To do that in the case of an aneurysm, we typically use covered stents. So, stents are devices that we place into the vascular system, and they are covered around a stainless steel or some sort of metal scaffold to exclude the aneurysm. So, it prevents the blood from exerting continuous pressure on the aneurysm wall to prevent it from growing, or it can cover the clot that’s inside the aneurysm to prevent it from embolizing and going downstream. Most aneurysms are treated endovascularly now, but there are still bonafide situations where open surgical repair remains the gold standard.

Host: Well, what are some of the risks of leaving a peripheral aneurysm untreated?

Joseph Vincent Valenti Blas, MD: Yeah, again, these are silent most of the time. When they do cause symptoms, it’s because they have gone down and behaved in one of those manners that we listed earlier. So the symptoms that someone would have if these aneurysms were to become complicated, meaning cause complications, would be obviously a high-risk of mortality if they bled into a surrounding space and we weren’t able to address it quickly.

You could get what’s called acute limb ischemia, which is a sudden cessation of blood flow to a given organ or appendage that would cause an increased risk for amputation if we weren’t able to overcome that situation within a relatively timely fashion. So, limb loss, amputation or even life loss from the blood loss. Those would be the big ones.

Host: Gotcha. Thank you. Well, you touched on this a bit earlier, but I just want to come back to it. If someone has a peripheral aneurysm and they have it treated, does that still increase their chances of developing another one later possibly?

Joseph Vincent Valenti Blas, MD: Yes. By and large, anyone who has had an aneurysm should undergo surveillance for the aneurysm that they have. If they’ve had a repair of that aneurysm, they should undergo surveillance of the repair of the aneurysm that they have, and if they have an aneurysm that is either repaired or under surveillance, they should be screened for other aneurysms elsewhere in the body.

Host: All right, and my last question today, Doctor, are there steps that people can take to reduce their risk or even prevent peripheral aneurysms from forming?

Joseph Vincent Valenti Blas, MD: The big thing is to modify your risk factor profile. These aneurysms are associated with age, smoking, atherosclerosis and known aneurysms elsewhere; by controlling some of the lifestyle things that can cause aneurysms, like smoking and the development of atherosclerosis that’s usually a part of having high blood pressure, high cholesterol, diabetes or renal failure. Those are the biggest opportunities to decrease the chance of you forming these aneurysms.

Host: That was Dr. Joseph Blas. For more information, check out Flourish.

If you enjoyed this podcast, please share it on your social channels and check out the entire podcast library for topics of interest to you. I’m Caitlin Whyte and this is Flourish. Thanks for listening.