Beyond utilization: the real-world impact of IVC filters

Episode Transcript

Recorded live from the Cook Booth at SIR and featuring leading experts in the field of interventional radiology discussing a wide range of IR-related topics, this is the Cook@ SIR Podcast Series.

Hey, everybody, this is John Kaufman. I’m here with Sarah White and Sebouh Gueyikian. And we are at SIR, live. You can hear it in the background. This is part of the Cook@ SIR Podcast Series. And we are going to be talking about vena cava filters. And we’ll start by just having each of you tell us a little bit about yourselves and your current filter practice. I’ll start with you, Sarah.

So I’m Sarah White. I work at the Medical College of Wisconsin. I’ve been there for my entire career after fellowship. So filters are obviously the bread and butter of what we do in IR. We put a ton of filters in trauma patients—big trauma population—cancer patients, preoperative surgical patients—you name it, they come. So big filter practice.

Sarah, John, thanks for having me. My name’s Sebouh Gueyikian. I’m the chief of IR at Endeavor Medical System. We’re a nine-hospital system around the Chicagoland area. This is in this incarnation of my life. This is my seventh job. So filters and workflows around filters are something that I’ve had to deal with in each one of my jobs. And definitely part of the bread and butter work of IR. Yeah.

Yeah. So it is part of our bread and butter. I’m in an academic practice in Portland, Oregon. And what we’ve seen over the last probably 10 years is a decline in filter utilization. It seems to be leveling out. And I think that’s reflected in a national literature. And I’m just curious what your all thoughts are on: Are we getting to the right place for filter utilization in terms of the percentage of patients that— with VTE or not that are getting filters, or do you think there’s more to go?

Sorry, a big dog just walked by. So sorry.

Yeah, we are live.

Watching the dog. Sorry about that.

We are live.

I’m paying attention, John.

I do think that we’re at appropriate levels of filter utilization. I think as time’s gone by, there’s better guidelines, better utilization of anticoagulation. Currently, in my practice, I work with a big team of vascular-medicine people who are all over the guidelines and anticoagulation protocols. So— and I practice in Cook County, which is the most litigious county in the country. So working in the filter space, I’d say our utilization of filters is spot on for the protection utilization that we’re using it for.

I would say, in addition, I think because IR has evolved so much in the DVT and PE practices, we’re now doing thrombectomies for DVT, so there’s not necessarily a need to put a filter in if you’ve sucked out the clot. And doing pulmonary thrombectomies, a lot of the cases that we were putting filters in were for patients that had massive or submassive PEs that we weren’t going to do an intervention on. And if they had thrown one more clot, that would’ve tipped them over. So just for pulmonary preservation we were putting them in, putting them on anticoagulation. Pulmonary status gets better, and we take them out. We don’t do that anymore, because we’re doing pulmonary thrombectomies. So I think as IR evolves, I think the filter practice has evolved with it.

Yeah. I think there’s an important theme there that we are much more involved in the longitudinal management of these patients. So it’s not just the episode of, can you put this device in and we’ll take care of the rest, but we’re helping make decisions about what therapies, and then we’re following up. And it leads me to my next question for— once you put that filter in, who’s following it in your places? Whose responsibility is it? How is that being done? What are the goals of the follow-up?

As soon as a filter— a retrievable filter gets put in, theoretically, whoever puts the filter in— and again, the attendings were terrible at this, but we send a message to our staff to say, “This is a retrieval filter; please follow up.” And then it goes into a queue. Now, they know that attendings are putting filters in all the time by ourselves. And so there’s a list of patients that we’ve done a procedure on every day, and then that— the nurses check that. The problem, of course, is that we have one nurse that’s doing that. So things fall through the cracks. At some point, in about six weeks, she’s checking in to see how things are going, and then she’ll run it by us. Does this seem appropriate? Does this not seem appropriate? Because of the high volume of clinic patients we’re seeing now, that follow-up clinic visit is now being done by an APP, which— good or bad. Sometimes we have some challenges with that, but sometimes it’s really spot on, and then they’ll get scheduled to come back and— for us to take the filters out.

Yeah. Our follow-up is done primarily by our APPs. I would say they do a great job in filtering out, to make a pun, who needs a complex intervention or— always good at figuring out, is it time or not time. How about you?

Yeah. Can I ask about the timing of follow-up? When do you evaluate those patients for if they need to have their filter taken out and when they’re going to take it out? How often are you reviewing those lists? When are you looking at them? When are you making decisions about them?

Yeah. So in about six weeks is when they first look into it, unless there’s a two-week window, and they want them out sooner than that. So typically at six weeks we evaluate, and then it’s usually about once a month that they’re looking back through that list to see.

Got you. Yeah. So currently in my practice, we have vascular medicine involved in a lot of the filter placements, and they run a filter clinic. So if the filter request and placement comes through them, they’re all over managing their anticoagulation and then requesting the filter to get removed. It seems like a little bit of a step backwards, but they’re all over it. But there are patients that don’t come through them, so we have to be responsible for those. And we established a once-a-month look-back at those patients.

In my previous practice, where we covered 14 hospitals on the eastern half of Wisconsin, it became a challenge to track all these patients. And it turned into an APP-designed process, where it was a once-a-month look-back to really track and trend all these patients, and it became a huge Excel spreadsheet. We looked for electronic methods of trying to do it inside. There was a SVS product that was out there that was really, really expensive. There was some other products. I haven’t really been able to see a way to do it inside Epic efficiently, but currently we’re doing “pen and paper” in Excel to keep those patient lists.

We’re at four to six weeks, and when it goes in, this is automatically set up. But let me just ask you, what about permanent? Sarah, you said there might be a distinction between those that you think you’re going to take out and those you do not. What about patients who have a permanent filter? It’s intended to be permanent. Do you think there needs to be any follow-up for those patients in terms of— specific to their filter?

Well, we certainly don’t have the bandwidth to do it, and we don’t. Maybe there should be, but we certainly— we do not.

Yeah. At the time of placement, we try to select and decide if the patients are going to be getting retrievable filters or permanent. And once the permanent goes in, we just assume that they’re going to be in permanently.

Yeah. And I wonder if that’s an area for us all to think about, because the complication rate of indwelling filters is linked to the amount of time they’re in. And so these are— the people that have it at permanent are potentially the ones that are going to have the fractures or migrations or thromboses. So it would be an interesting thing to think about. What about that population? We’re so focused on getting them out to prevent complications, but if we’re leaving them in, granted, many of those patients may not have as long a life expectancy—

Right.

—as you might think, but maybe food for thought.

Yeah, because most of our criteria for the permanent filters— there is not a long lifespan associated with those pathologies. There are some younger people who have some indications that might lead to multiple decades of needing a permanent filter, but a majority of them, the lifespan is not there for it.

Yeah. We have some legacy patients that had filters placed in a trauma setting 20 years ago, and they resurfaced now, and— “Oh, they have a filter. Can you take it out?” It turns out it’s something not really designed to be taken out, and they’re having no problems with it, but what do you do with them? So let me throw another question at you. We have had the instance of we place a filter, and then five days later, we take it out. They’re now on anticoagulation, and we want to discharge them, and we’re worried we won’t be able to follow up on them. We take the filter out, and they’ve been on anticoagulation for maybe 36 hours. So we’re good. We think they’re safe. How would you respond to that? Because we struggle a little bit with this.

Yeah, that’s a very common response. And it’s typically in the trauma population, right? They’re going to leave. We don’t know if we’ll ever get them back. And I think as long as there’s not been some history of bleeding in the past, they’re not a GI bleeder or something else that we think that they’re going to fail anticoagulation, I think we lean towards they know their patients, and if they think it’s appropriate, then it’s probably appropriate, and we’ll take it out. But I’d say, yeah, that’s a struggle, because we get that a lot.

Yeah. Sebouh, do you deal with that?

Absolutely. Anticoagulation is magic. Don’t you know that? That the anticoagulation overcomes all physical properties of clot migration and embolization. So the second that people get anticoagulated, they think that there’s no longer a need for filtration, but you really have to look at the patient and see and worry about the risk of clot mobilization. So it’s absolutely a concern. And then if they’re not going to come back for a filter removal, how do you feel about leaving that filter in somebody who might never come back for a removal? So now you’re looking at leaving a filter in for somebody for the next 40 years or 30 years. So is it better to pull it before they leave the building? It’s a tough situation, but that’s why IR should be having that conversation with the patient and making those decisions before they leave the building.

Yeah. I think that’s a key point. It’s just we need to be engaged, and we need to be part of that follow-up. We often have a saying, I guess, in our practice: If you place the filter in, then you own that filter, and you have to follow it. You’ve all— have different practices, and maybe in multiple different practices, and we’ve alluded to how we’re following up. What do you think the most effective strategy is for increasing your retrieval rate to an appropriate level? I mean, I am not in the camp of the indication for retrieval of a filter is the presence of a filter. I think you’ve got to really understand why you’re taking it out and why it needs to be taken out. But what strategies have you found that have been like, this is the thing that just helps us the most to get these patients in who need their filters out and get them out in a timely manner?

I’d say the collaboration we have with our hematologists; they do a really nice job of taking care of patients. And if they have a retrievable filter and they think it’s going to need to be permanent, they’ll have them come in, we’ll take out the retrievable, put the permanent in, just for complication risks. And that same collaboration we have with our vascular-medicine folks, just like you do. And then the trauma teams are pretty good about if they’re seeing a patient back for whatever wound follow-up, and they see that filter in there and, “Oops, we forgot to tell you that this filter needs to come out if it was put in somewhere else” and they got—

Because sometimes they’ll get transferred to us for higher level of care for surgical management, and they’ve already had a filter in. So I think having that nice collaboration with those other faculty or specialties is really nice. I get calls probably once a month saying, “Can you look at this? Should we put a filter in? Shouldn’t we put a filter in? Should we take it out? Shouldn’t we take it out?” And you take that phone call on the fly. And I think that’s a nice relationship to have and helps with retrievals.

So collaboration being in the mix of the people managing the filters.

Yeah. I’ve found that really empowering the patient at the very beginning, during the consenting process. Most patients don’t really like the concept of a metal foreign body living inside them. And if you tell them that this is a temporary product that could be there for three months, could be there for six months, you set the stage that this is not meant to be with them forever, and they will be highly motivated to come back and try to find a way to get it out. So we definitely sell it as a retrievable filter at the very beginning. And then the patients are the one who drives the conversation about when can this come out and why can’t it come out soon? That’s a different conversation than what we used to have with patients around filters.

But, John, I like what you said about just because you have a filter does it need to be retrieved? So I had a patient that was seen by the nurse practitioner Monday morning, came in. I was thinking, “Why are we taking this filter out? This woman has cancer. She’s pretty sick. Should we or shouldn’t we be doing this?” We gave her a little bit of sedation, took the filter out, and all of a sudden she crashed. And, “Oh, I ruptured the cava. I did something bad.” I looked back at the pictures, no, and we’re coding her. And then we put an ultrasound on her chest, and she’s got a pericardial effusion. I was like, “Oh my gosh. We have just ruptured.” We’ve called CT surgery. We slam her down to the trauma bay, and it turns out that it’s just progression of disease, right? And so did that filter really need to come out?

And so that was the question back to me from the referring docs is, why did you take the filter out? Well, because it’s retrievable, we take them out. She had been seen, and she was appropriate at the time. Three weeks had gone by between when she was seen and she came in, and the pericardial effusion was chronic, and it wasn’t anything that we had done. It wasn’t a complication. The complication was that when we gave her sedation her preload dropped and she coded. So she did fine. She went home after that. But, I mean, I think once the train is moving in the direction, you have to think about it, even if the patient’s on the table. And I will always remember that lesson is even if the train’s coming at you, if she doesn’t seem appropriate on the morning of, then just don’t take it out, and it’s fine. Just keep it in.

Yeah. Retrieval is not always a benign process, right? It’s viewed as taking off a Band-Aid or something, but it can be— it can get complex. And that is such an important point. And I appreciate you sharing that, because we need to be out of the mindset of just because we can do something or something is designed to be used in a certain way, we have to execute that no matter what. It all gets back to being a physician and thinking about the patient as a whole and what’s really in the best interest of the patient. And this is where the guidelines— that’s why they’re called guidelines, right? Because we have to do our own interpretation and look at the person in front of us. Where, though, do you think we should be all aiming to be for our— If we put in a hundred filters, where should we be aiming as a reasonable retrieval rate?

Or is that even a reasonable question? Maybe it’s just so practice-dependent, you cannot have a number like that. You just want to try and get the ones out that you know should come out. I mean, because we see— there are all these comparisons. There are articles about retrieval rates, and we’re not retrieving enough, but sometimes maybe in certain populations, Sarah, like yours, it’s appropriate not to retrieve.

Yeah. I can say in my last practice in Wisconsin where we did a lot of pre-screening and a pre-decision about permanent versus retrieval, our retrieval rate was in the high 80s. I think we did a really good job of deciding whether people were getting permanent or not, and we made that decision. Currently, where I’m at now, vascular medicine weighs in on retrievable versus not, and they’re asking for retrieval and really advocating for retrievable filters in patients that you really wonder if somebody who’s 93 years old is going to really successfully be on anticoagulation for long periods of time.

And so I think if you can remove large portions of your filter population from the retrieval population and put permanence in, your retrieval rate will go up and will be better and look better because you’re doing retrievals and not being in those situations where maybe you’re taking filters out in high-risk people with lots of comorbidities. But I do think it’s practice-dependent. I think it depends if you have a lot of trauma versus a lot of malignancy versus a lot of really old patients.

Yeah. I think more than we have to have a rate at which we’re taking filter— We need 80% of the retrievables out— I think it’s more important to get the appropriate filter in the appropriate patient and take them out at the appropriate time. And so I think that’s a really hard number to get at, because I could just switch and put permanents in everybody, and then I don’t have to worry about my retrieval rate. My retrieval rate’s great. It’s 100%, because I put one in and I take one out. So I think making sure that the appropriate filters are going in— I think we have the benefit now of having a convertible filter. So if we have that patient population that’s 93, and we’re like, “I’m not really sure if they’re ever going to go on anticoagulation,” we have the benefit now of the convertible filter. And I think we lean on that a lot for those patients that we’re just like, “I’m not sure about this.” But at least we have the option that we could convert it and leave the patient.

I also use the Günther Tulip® filter, which has a retrievable indication, but I’m confident I can leave it in as a permanent filter.

As we walk around— it’s interesting you mention the Tulip. So we walk around this hall, right? We’re here at SIR. There are a number of filters. There has not been a lot of change in filters, and that’s one of the questions I wanted to bring up here is why do we think there doesn’t seem to be a lot happening in the filter space like there is in the ablation space or the embolic space, and do we need to be having some innovation? Are there things that we could be doing better, or are we at a steady stage? Just curious what people think.

I’d love to know what our industry partners think about that, because I can’t tell you how many times I’ve put a filter in, and the patient goes back to their room, it 11:00 at night, and then all of a sudden you see them the next day, and they’re like, “You just put a filter in and there was a TV ad and I was supposed to call this number.” And you’re like, “Oh my goodness, this is”— So I think litigation is really a piece of this, and that may also have some bearing on how many filters we’re putting in. Patients are pushing back and saying, “Do I really need this? I saw that ad on TV.” Because they’re up all night, and that’s what’s playing in the background. So I think the filters we have now are pretty nice filters. We know how they work, they operate. So I’m pretty comfortable with the filters that we have. I like them. I think they’re doing a good job. There’s always room for a little bit of improvement, but I think with all the iterations, the ones we have now are pretty good.

This is a very dramatic question. You hear the music in the background as soon as we started answering this question. So this is a very important one.

And I will say that most innovation comes from struggle. There has to be a problem or a situation that people are trying to address to find a solution to. And I think like Sarah was saying is that right now I think there’s a decent portfolio of filters on the market that are a solution to every situation that you need a filter for. And I don’t really think there’s a gap anywhere in there that we need where we’re saying, “Oh, there’s a filter that I wish that somebody would make that would really take over the space.” So I think we’re really comfortable with the filters that are on the market right now.

Yeah. Maybe in a situation in which we need 20-, 30-, sometimes 40-year data, devices that are stable, maybe an advantage, but we live in this world, we always want the new, the next very— So just curious, if you were to give advice to someone who’s starting out and coming to a new hospital, they believe in the value of filters in appropriate patients, but they’re facing a lot of resistance of people who are suspicious or concerned about filters, suspicious that— are they really providing value? Do they really add to the care of a patient who has VTE? How would you recommend they go about introducing filters and ensuring that they’re going to be used in a responsible way in that situation?

That’s an interesting question. A lot of the times it’s just the clinical interaction with the patients. This is strictly a prophylactic device that you’re protecting the patients for, and it’s really tough to imagine a situation where physicians aren’t there out looking for the patients’ best interest, but you have to be in the patient’s room talking to the patient about their care and their future. I think it’s really hard to do that from the reading room downstairs. So if you go see the patients, and you talk to the patients, most of the patients want a protective device, and they don’t want it permanently. So it’d be really tough to be in a situation where you could talk a patient out of a protective device while they’re sick. So I just find that the clinical interaction with the patient is usually what ends up being the most successful thing.

I would agree. I think anytime in IR that we can be clinicians, which we are all day, every day, I think that just shows our referring colleagues that we’re not plumbers. We are actually doctors, and we’re going up there and saying, “No, I don’t think this is appropriate for a”— They ask for a filter, and you say, “You know what? I don’t think this is appropriate. I don’t think this patient actually needs a filter.” Showing them that you have a clinic, showing them that you’re following up. When you take the filter out, calling them and saying, “Oh, I saw your patient back, filter’s out, back on anticoagulation, we’re good to go.” I think having all of those kind of communications are really quite important.

And then sharing your anecdotal story is— I had a patient that Bill Rilling actually put a filter in, and I was so worried. It was a trauma patient, and then they got a KUB, and the filter had flipped on its side, and I thought, “I got to go take this thing out. We got to get it out now.” It was a week after he had put it in. And so Saturday I called the patient down, I do a venogram, and, boy, was there the biggest clot I’ve ever seen. This poor young guy who had had a terrible trauma, he was alive because of this filter. So I think sharing stories when they do catch something—

Right.

—so they know that that young person could have been dead had this filter not been in place, I think is always an important thing that— because we never see it. You know it theoretically happens, but it’s very rare that we see it. So when we do see it, making sure those referring teams know that these actually do save lives.

Yeah. I think we all feel that way, those of us who place them, obviously, because we believe in the devices, and the data have been hard to come by showing protective effect in terms of survival. It definitely shows— the data shows there’s less PE—

Right. Right. Right.

—if we have a filter, but survival impact has always been a little harder. So it remains, I think, a little bit of a nuanced discussion. My feeling is if you show that you’re thinking about it, you’re speaking with the referring people, you’re taking ownership of the patients, you’re making sure you get them out, you can alleviate a lot of the concerns that people have about placing devices, because there are times when we feel like this patient really probably needs a filter and there’s this resistance. “Well, it’s a horrible device, and it’s going to create all these problems.” And I think we have to be out there in person to combat that and make sure the patients get the appropriate care. What is your—

One last question, then I’ll let you guys go. Someone comes in, they’ve had a filter for about a year that needs to be taken out, they show up in your clinic. What workup are you doing for that before you take them out? Say they’re— assuming they’re stable on anticoagulation or whatever, their PE risk is gone, you know that. But what workup are you doing on a patient before you take out a filter for someone, a filter that’s been in a little bit amount of time where you haven’t seen it for a while?

Yeah. So any patient that has had a filter in for more than six months gets a CT venogram. Everybody gets a lower extremity duplex. If they have clot, that doesn’t— that’s not necessarily mean we’re not going to take the filter out in about a year probably. They may not have clot, but if they have something chronic, that’s a discussion with the referring team. Does it make sense, doesn’t it make sense? Is their anticoagulation stable or not? So CT venogram for sure, lower extremity duplex, then they’re seeing us all in clinic as we talked about. I like to make my body into a filter, and show them that the struts can penetrate, and then show them actually on their imaging the day of placement—

No one could see that, but it was very convincing.

That was amazing.

Yeah, yeah, ouch.

I looked like a little finger putting my arms out. And then showing them if there’s tilt or not, and then having that discussion that if we think it’s a straightforward retrieval, we’re going to try for that, but in only 80% of the time we get it out. And then if we have to do more provocative maneuvers, we’re going to come back at a later date, and we’ll have another discussion about it. And then putting a filter in their hand and showing it to them and letting them touch it. So I think that’s what we do at a year. If it’s really tilted, then we’ll have the discussion about a more complex retrieval and what that means and do they want to go down that path. And I can’t remember a patient that said no, they all want to go down that path once you have that discussion with them, but that’s our standard typical workup for—

But they really appreciate the discussion.

Yes.

That goes a long way.

Yeah.

How about you?

We’re a little bit more pragmatic. Year is our sweet spot where we just see them in clinic, evaluate symptoms. If they don’t have any lower extremity symptoms, they don’t have any episodes of massive leg swelling one morning where it seems like they caught a big clot since the filter’s gone in, we’ll just attempt a simple retrieval, but after a year, then we’ll go down the pathway of a CTV to see if there’s any tilt, penetration, a lot of the other stuff. And then we’ll still attempt a simple retrieval under moderate sedation. And if it doesn’t go well or there’s some tilt or covering of the hook, we’ll bring them back for a complex retrieval under general anesthesia.

Yeah. I think we’re probably all aligned. A year is about when we’re saying we need some kind of advanced imaging, and a KUB just doesn’t quite give you the full picture of what you’re dealing with in particular looking for angulation and penetration, things like that.

And that’s if it’s one of our filters. If it’s an orphan filter— like you were talking about filters coming in from the outside, I call those orphan filters where somebody else placed and was abandoned. An orphan filter taken by— placed by somebody else, those get a CTV, because, yeah, you just don’t know enough about when it went in, how it went in, the operator who put it in, the level of the renal veins, a lot of the other things. There’s a lot of assumptions that we make when it’s our filter that it was placed and positioned appropriately. I can’t know that without cross-sectional imaging for orphaned filters.

Well, this is a topic I personally love, and we could talk for days about filters if you ask me, but we’re going to have to wrap up. Any final comments or observations you want to make before we wrap up where, again, in the middle of the meeting, people are milling around us. There’s a lot going on here.

I’d say there’s been a big evolution, just in my career, of filters. So when I first started, I remember being a first-year radiology resident and looking at chest x-rays and saying, “Oh look, there’s a filter strut and there’s a filter strut.” My radiology— the chest guys were like, “Sarah, you don’t know what you’re talking about.” I’m like, “No, no, those are filter struts.” And now I haven’t seen a filter strut in a extraneous place and— since I joined the Medical College of Wisconsin, so in 15 years. So I think we’ve made good progress. I love that SIR published guidelines and now we can go back and say, “This is appropriate. This is probably not appropriate.” So we have some footing to stand on. So I think there’s been a nice evolution both with technology and with guidelines and clinical practice. So I like where we are now. You asked, “Are we in a good spot?” I think we’re in a good spot. Do we have place to go? Probably, but I think we’re in a pretty good spot.

Great.

Yeah. I would say that everybody’s really enamored with retrievable filters, but people should really be comfortable with permanent filters, and the criteria for putting in a permanent filter, I think, is still there for people who are really sick, really old. A pulmonary embolism from a big clot is a devastating complication, and there’s high-risk populations of patients that just don’t get better, and you should help make that decision for those patients and put a permanent filter in them. So I have plenty of partners who come out of training that have never placed a permanent filter, and even though in their mind they know that this patient’s never going to get the retrievable filter out, they just have never had the experience of putting a permanent filter in. And I think that’s a lost part of the filter world that we really need to have as part of our bag still.

I would agree. I think of all the shifts in my filter practice, we are now putting in many, many, many more permanents than we used to, for sure.

Well, this has been great. I think you hear a bunch of themes here, involvement in the care of the patients, being really thoughtful about your indications, having a plan, not being afraid to say this is a destination filter and managing the patient that way and being mindful before you take it out of— making sure you have enough information to get the filter out. No, this has been a great conversation. I want to thank both of you for participating and hope you enjoy the rest of the meeting.

Thanks, John.

Thank you.