CAROTID ARTERY STENTING TAMPA GENERAL HOSPITAL TAMPA, FLORIDA September 28, 2006

Transcription

1 CAROTID ARTERY STENTING TAMPA GENERAL HOSPITAL TAMPA, FLORIDA September 28, :00:00 ANNOUNCER: Every 45 seconds someone in the United States has a stroke. Stroke, or brain attack, occurs when a part of the brain is deprived of blood and oxygen, often as a result of a carotid artery blockage. Patients suffering from a blocked carotid artery now have a minimally invasive treatment option. During this live webcast, physicians from Tampa General Hospital in Tampa, Florida, will review a carotid stenting procedure to clean out a blocked artery. They will also answer your questions live as taped highlights are shown. 00:00:32 BRAD JOHNSON, MD: The carotid stent procedure is one that s taken a while to develop. People that get blockage in their carotid artery in their neck, we re concerned about that because when they reach a significant narrowing of that artery, they have a greater tendency to break plaque off, and it goes in the brain and gives them a stroke. 00:00:52 ANNOUNCER: For many patients with blocked or narrowed carotid arteries, this procedure is an optimal alternative to open surgery. At any time throughout this program, you may questions to the physicians by clicking the MDirectAccess button on the screen. 00:01:11 BRUCE ZWIEBEL, MD: Hello, I d like to welcome you all here to Tampa General Hospital. We re going to be discussing today carotid artery disease and carotid artery stenting, which is emerging new technology for the treatment of carotid disease. My name is Dr. Bruce Zwiebel. I m an interventional radiologist with Radiology Associates of Tampa. I m joined here today by Dr. Brad Johnson, a vascular surgeon with the University of South Florida, and Dr. Jim Lefler, who s a neurointerventional radiologist also with Radiology Associates of Tampa. During the course of the show we encourage you to submit questions, and we would plan on answering them during the course of our discussion of this case. And just as a point of fact, it ll probably be important for us to explain why this case is not live. We ve done live cases before in this particular type of venue, but with these patients the acuity of their problem actually precludes us from putting somebody on hold for, say, a month or two months to schedule a procedure. Usually these procedures, as you ll see today, are a bit more life-threatening and have a bit more acuity to them, so we were forced in this particular case to tape this case live, done live, and today we plan on discussing it with you, showing live video footage from that day of the case, and trying to interject some comments as we go through. Best way to start, I think, is to have Dr. Johnson discuss with us today some of the facts that we know about stroke and why it s such a pressing issue today. BRAD JOHNSON, MD: Yeah, the main thing that I want to get across in this is that these carotid stents and also the surgery which I m going to explain, their main focus is preventing strokes. They you know, someone may say, Are they going to make us smarter? Could we have more blood supply to our brain? No, it doesn t do that. We only wish it would do that. But the striking stroke facts that we have is that every 45 seconds someone in the United States has a stroke, and 700,000 a year are going to have their first

2 attack of stroke, and then we ve got 200 recurrent attacks of strokes every year. There are some other things about it. It happens in men and women equally, and the other fact is that African-Americans have twice the chance of having a stroke as Caucasians do. Stroke accounts for 1 in every 15 deaths in the United States, so it is a significant medical problem in the United States. It ranks third among all causes of death behind the diseases of the heart and cancer. And so we re here to talk about a ca a procedure which will prevent those strokes from occurring. On the average about every three minutes someone dies of a stroke in America, and it is the leading cause of serious long-term disability in the United States. You know, if you go to a rehab center or a nursing home, a lot of those people have suffered a stroke. And the cost to our society is tremendous: $53 billion a year is the cost of strokes direct and indirect. And the carotid artery is unique in the fact that it is the place where most of this plaque will accumulate in a very localized fashion, and these little pieces as the artery narrows further are going to break off over time and go into the brain. It s usually observed right at the carotid bifurcation, so it s easily accessed by surgery and also by stents. The standard operation which we ve been doing for 40-something years now is to go in with an open procedure in the neck and actually remove the plaque which causes the emboli to break off and causes a stroke. It s an open procedure. It requires an incision, and most people require general anesthesia, even though sometimes it can be done under a cervical block. Carotid stenting is something that s evolved over probably, Dr. Zwiebel, you could say, what, 8 or 10 years? And it s really a step up in technology. As a surgeon who does both the open procedure, the end arterectomy procedure, and the stent procedure, I was a little skeptical at first, but I ve become convinced now that this is a way to go for certain patients, and we ll talk about those patients today. The other thing is that it will easily open the artery up, and unlike diseases everybody -- in stents in other parts of the body we ve had trouble with stents reclosing, like in the hearts and the legs. Well, the disease in the internal carotid is localized at the particular area and it doesn t spread up the internal carotid artery as other arteries do, so the stent has been really good as far as durability in this particular area. The other things we re going to talk about today with this procedure is local anesthesia in a lot of cases, if you want to. Dr. Zwiebel s going to bring up and go through, along with Dr. Lefert s going to talk about the embolic protection device, which is a major advancement because initially before this our stroke rate was about 11%. So we ll go back to Bruce here. 00:06:04 BRUCE ZWIEBEL, MD: The next thing we d like to show you before we go ahead and begin to demonstrate the procedure and show you some live footage is actually look at some of the instrumentation that s available to us today. Dr. Johnson alluded to the filter device. And actually, we ve been doing the procedure here at Tampa General Hospital since 1996, and through the probably the first five years of that time period there were no filter devices available in the United States, and therefore we had none available here, so we were doing the procedure without a filter, and I ll explain what that filter means in a minute. But the complication rates, although they were extremely low here at Tampa General, nationwide and worldwide were quite a bit higher than they are today because of this technology. If you focus in here on my hand, you ll see there s a and you can come in real tight on my hand there s a metal scaffolding which which I m spinning right here, and on the top of that metal scaffolding is a covering which is actually thick enough so that pieces of plaque that break off from the carotid artery, which is located in your neck, and would normally travel to the brain are actually caught in the top of this umbrella and don t go to the brain. But there s enough porosity of this so that blood can flow through it and maintain blood flow to the brain, so at no point in the procedure is the brain deprived of blood flow. So this you ll see this filter device. We re going to use it today during the case, and you ll see it go up into the carotid artery, and then we re going to retrieve it at the end of the case and take a look inside and see what debris has been retrieved. Now let s take a

3 look at the stent we use. And if you can maybe zoom out, you can get a perspective on just how long this is. Now, the reason 00:07:57 BRAD JOHNSON, MD: That s not the entire stent. 00:07:59 BRUCE ZWIEBEL, MD: The stent, as Dr. Johnson said, the stent actually sits in the very tip by my hand over here, and we ll get a close-up of it in a minute, but this is the length of the entire device. This is a deployment device. The reason why it s so long we actually begin this procedure, and it may seem counterintuitive, but we begin this procedure from the groin area because that artery is extremely accessible to us it s close to the skin, it s a large artery, and it s one after the procedure s over we can gain control of with our hand and not have to open the patient up. So this actually travels from the groin up into the neck where it s deployed. If you come down now closely on my hand, I ll show you a little bit about the stent. The tip of this catheter, this gold portion, actually houses I ll get a profile actually houses the stent in it. You can see the darker area is the stent. Now the way this thing works is that the and you can zoom out is when you pull this cartridge back, the outer sheathing of the stent pulls back and therefore deploys the stent. So I m going to unlock it, and then as I pull this back, you re going to begin to see now if you really get up close on this you ll see this is the stent deploying, the struts of the stent. It s almost like a chain-link fence wrapped in a ring. And as I pull this membrane back Whoop. Now it just took off. There it goes. So here s the stent. And you can really zoom in tight on this. This is actually the stent open. It s made of a metallic material that is such that when it hits the heat of the blood, it expands to a predetermined shape and size and therefore stays open, and the plaque is wallpapered against the wall. Now that I ve shown you some of the equipment, we re going to break away to some animation of exactly how this works. If I can just borrow that, Brad. 00:09:56 BRAD JOHNSON, MD: Yeah, yeah, sure. 00:09:58 BRUCE ZWIEBEL, MD: And this is the procedure sort of in an animated way. If we focus in on the screen, we ve now gone through the blockage, which is this yellow plaque, deployed the filter, which I showed you up here. This artery now goes to the brain. We put a balloon in here to open up and expand the plaques that our stent will fit. Little pieces may break off and are now trapped in the filter. We now put the stent in, retract that membrane, the stent is deployed. We next pull the stent material out. We next bring in the balloon, open up the stent to its maximum diameter, therefore wallpapering the plaque against the wall. More pieces may break off at that time and get captured by the filter, not go to the brain. We now we now retrieve the filter, take it out, stent stays in place, and there s brisk flow to the brain. We re now going to have Dr. Johnson talk to us a little bit further about the procedure and we re going to break into some of the live footage. 00:10:56 BRAD JOHNSON, MD: Okay. As Dr. Zwiebel mentioned, the reason we come Everybody always asks, Why do you go so far? Why do you go from the groin? Well, like he said, the femoral artery is the easiest access, and we ve been doing access in the femoral artery for many years. And so the procedure itself, what we do is we prep we usually give a little local anesthesia, we ll prep up the groin, and them from there we ll take a needle and access into the artery, and then place a guidewire followed by a catheter down into the femoral artery. And from there we re going to thread this all the way up into the carotid artery from here. Bruce, you want to? 00:11:30 BRUCE ZWIEBEL, MD: Yeah. We re going to now break into some live footage. I want before we do that I just want to encourage anybody out there who has questions about this procedure or really anything involving this type of this disease to please us questions

4 and we ll go over them during the broadcast. We re going to break away to some footage, and we can look at the screen here. This is a case that we performed about a week ago, and Dr. Lefler s going to take us through some of the things going on here. 00:11:59 JAMES LEFLER, MD: And this is where we have already prepped the right groin and we re gaining access into the femoral artery in the groin with a needle. Once we gain access with the needle, we pass a wire, and over that wire we pass that small tube that s a catheter into the right groin to give us access to the vascular tree of the body, essentially -- primarily the aorta, but but after that we use it to get back up get into the head vessels. 00:12:31 BRUCE ZWIEBEL, MD: Just as a question, Jim, when we looked at the wire and catheter going in, are there any considerations in terms of, you know, what type of patient anatomy is favorable, what type is not favorable for this type of procedure? Maybe you can cover some of that. 00:12:46 JAMES LEFLER, MD: Well, of course, the more favorable patients are those patients that don t have atherosclerotic disease in their legs or thinner patients because you have easier access to the femoral artery. However, there s usually very little patients that we cannot access in the groin. 00:13:04 BRUCE ZWIEBEL, MD: So basically, there s no there s really no limitations for access. 00:13:05 JAMES LEFLER, MD: Correct. 00:13:07 BRUCE ZWIEBEL, MD: Okay. I don t know if there s any questions that came through, or we can continue on with the footage. Perhaps maybe we ll go to the next segment of footage here, and we re going to begin to move into the procedure a little bit further. We ve now introduced the wire in the catheter, and now you can tell us what we re doing here, Jim. 00:13:22 JAMES LEFLER, MD: We re have the catheter in the groin and up into the neck vessel, and we re trying to pass a wire to try and get into his right carotid to have the catheter pass over the wire and give us access to the carotid artery, right where the red dot and highlighter is. Once we ve achieved accessing the right carotid artery, then we can image the right carotid artery and do some measurements to try and figure out which stent is the right-sized stent for the lesion and what the lesion actually looks like. 00:13:59 BRUCE ZWIEBEL, MD: So here we re actually injecting dye through the catheter that we had introduced into the neck artery, and on these screens are the pictures that were taken; you begin to see them right here and here. They re actually pictures of the neck, and we ll begin to see some of the blockage. Maybe you want to comment. I ll put my pointer on where the disease is, Jim. 00:14:18 JAMES LEFLER, MD: Yeah, that s the fork in the vessel down low is where the common carotid artery sits in the neck. And the common carotid artery has two branches, one that goes to the face vessel and another one -- called the external carotid artery -- and then the other one, called the internal carotid artery, which goes to the head, and that one has the area of stenosis. And then what we also do is we image over the head before image over the vessels of the head before we put the stent in to make sure which vessels are open and which vessels are 00:14:47 BRUCE ZWIEBEL, MD: This is actually the patient s brain, and you know, it s very important for us to image the brain because, in fact, what we re trying to prevent here is a stroke, and we want to make sure that the distribution of arterial supply that we re now going to open

5 doesn t have any problems that s further ahead than we re fixing and also make sure that we know what vessels are patent before we start so that when we finish the procedure we know if any of them are missing. I think that s important to know. Just -- if there s any questions that came through, we can take them if somebody 00:15:23 BRAD JOHNSON, MD: Bruce, we might bring up one thing here is the fact that a lot of people say, Well, why haven t we heard of this? Well, as you and I well know, it took a long time to learn how to do this, and there s only certain places that are approved, and you can talk more about the approval process of who gets stents, and so forth. 00:15:39 BRUCE ZWIEBEL, MD: Yeah, I think it s important to know that and I guess one of the reasons why we re trying to bring this out to the public is that we ve been doing this procedure here at Tampa General, like I said, since It actually is what I would consider to be a new procedure these days; Medicare has just approved the procedure about a year and a half ago. So there are many centers throughout the United States who are now trying to gain experience and who are now trying to learn how to do the procedure. I think that if there s any procedure and you all, you two might want to jump in on this that if there s any procedure where experience is an important predictor of success, I think this is one of them. And certainly places like Tampa General, where we ve done nearly 300 carotid stents, is extremely important in terms of success. Now, the other issue is complications. And you want to technically be able to do the procedure, but you also want to have very few complications, and that s one of the things Our complication rate here is well below the national average for stroke and other such complications as it relates to this procedure, and that s even including probably half of our stents were done without any type of filter or carotid protection. We now have a couple of questions that came in, and maybe let s see, now somebody commented that An MRI indicates that my left carotid artery is 100% blocked. The blockage where the artery the blockage exists as it exits the heart. Can the stent procedure be used to open the artery? So I think what the patient is referring to here is that the artery out of the heart -- is probably not exactly out of the heart, it probably comes off the aorta, which comes off the heart and then eventually goes to the brain -- and their artery, their carotid artery, is 100% blocked. In that type of scenario, we can t open that vessel up and effectively provide blood flow, but maybe, Brad or Jim, do you want to comment on what the stroke rate is with somebody with 100% occlusion? 00:17:48 JAMES LEFLER, MD: Well, sometimes the MRI will overestimate the degree of stenosis, and therefore, 100% blockage on MRI may not be a 100% block. And if there is a small channel that we can get through, we could potentially treat that. But in addition, if it if it s been proven by other studies as well that it s 100% blocked, then it likely is 100% blocked. 00:18:11 BRAD JOHNSON, MD: Yeah, and the thing you have to remember is that once an artery completely blocks, there s no blood supply going up into the brain. And all the strokes are caused by not lack of blood supply actually from that particular area; they re caused by pieces of plaque breaking off and then traveling to the brain. So if you re already 100% occluded, no blood is flowing through that artery, so you don t have to worry about having a stroke from that plaque anymore, so you don t need to be fixed. Initially when we first started doing carotid end arterectomy, the open surgery, we actually did some patients who were completely occluded, and the outcomes were worse, and so we quit doing that. So if you are completely obstructed 100%, then this lesion should be left alone: no surgery or no stenting for this lesion. 00:18:51 BRUCE ZWIEBEL, MD: Before we get back to the case, I think there was another question that came in that I think is fairly interesting. Somebody was saying that they had pain when they turned their head, and then they had pain on the side of their neck. Could that be due

6 to a blockage of the carotid artery? And I think it s important for people to know that in all likelihood that s not related to carotid artery disease. The type the time that you are that carotid disease is evident is usually at the time of either strokes or mini-strokes, however you want to call it, where somebody has some depleted blood flow to the brain, so typically pain is not a predictor of carotid artery disease, it s usually a predictor of other types of things like muscular-skeletal problems and other things. 00:19:35 BRAD JOHNSON, MD: Yeah, most people will not experience any symptoms before they have a stroke, you know, and that s the reason we always have to look at risk factors. And the risk factors will say, Okay, by the way, somebody s got hypertension, somebody smokes, somebody has hypercholesterolanemia, and those people need to get an ultrasound of their neck to check for stenosis because, especially when we reach the age of 60 or 65, those factors will weigh in. Get an ultrasound, and that s one of the most accurate ways to determine if you have a blockage or a narrowing of your artery in your neck. 00:20:05 BRUCE ZWIEBEL, MD: I think maybe probably the best thing to do would be to let s break away to the next segment and we ll pick up some more questions as we go along. But let s let s grab the next segment. And what we re doing here is the vessel s been imaged. Jim, you can talk about the measuring and whatnot of the carotid artery. 00:20:22 JAMES LEFLER, MD: What we re doing here is we re measuring the size of the carotid artery as well as the size of both the internal carotid and the common carotid and the length of the area to be stented because the stents come in different sizes and shapes and we re trying to match the exact size of the carotid with the most appropriate stent. 00:20:47 BRUCE ZWIEBEL, MD: The I think it s important to also note as we re doing this that this is the patient s neck -- Just to give you some this is the jaw. This is actually a wire coming up from below, and we re [dropped audio] to the part of the artery that supplies the face that we were talking about earlier, not the [dropped audio] bring our system into place so that we can actually start the carotid stenting procedure. So this wire, which is marked all the way down here, is actually going up the external carotid artery and allows us to anchor ourselves so that we can bring our sheath system up into place. I think another question came up which is kind of interesting. Somebody in the audience asked about the fact that their daughter had a spontaneous carotid dissection and a blockage in their carotid artery, and that I think that brings up the point of what type of patients are we dealing with. Brad, you alluded to patients who have atherosclerotic disease and others, but there are other people who can have carotid artery disease. 00:21:58 BRAD JOHNSON, MD: Yes, there s different types of disease. The most common one is the one we re treating today, which is when people develop plaque disease as we get older from those risk factors I mentioned before. Another disease that occurs in the carotid artery is the fibromuscular dysplasia, which happens in women and happens in their 40s, and it s just abnormality not seen that common. And then for some reason some people will have a dissection, and what a dissection is, is basically your artery has three different layers, and for some reason it will the blood will create a hole through the first layer and will separate the layers up. And we see that it s not a very common thing, but when we do see it, a lot of times it will create symptoms. And the treatment for that the majority of the time is to just thin your blood out, and that actually works very good in most people. And then we search for is there an underlying reason why that spontaneous dissection occurred: Does this patient have fiber muscular dysplasia, do they have hypertension out of control? But today we re going to be more focused on the plaque disease that develops in people. 00:23:01

7 BRUCE ZWIEBEL, MD: But I think, you know, and Jimmy, you might want to comment, that patients who have carotid dissection can also be stent candidates. It s just a different disease process, and maybe you want to comment on that, Jim. 00:23:11 JAMES LEFLER, MD: Usually what we like to do is we like to, as Dr. Johnson said, treat them with anticoagulation or blood-thinning first, and if after a certain period of time that their dissection remains dissection persists and the narrowing persists, then we go ahead and decide to stent it if it s a hemodynamically significant lesion at that time. The other thing is that sometimes the dissections we get emerg on an emergent basis, and if at that time that it s significantly hemodynamic and the patients are symptomatic, we may go ahead and stent it at that time, more urgently versus waiting at a later time. 00:23:53 BRAD JOHNSON, MD: And that s been, like you said, one of the major advances because surgery would not work; stent was the only thing. You know, surgery, when we tried to operate on these people, most of them we actually harmed, so surgery is not an option in the majority of dissections, so it s been great that now we have a system we can use for these people. 00:24:09 BRUCE ZWIEBEL, MD: And the other thing at Tampa General, which we, I guess we probably see more trauma than most medical centers in this area. We ve had a number of patients who have sustained motor vehicle accidents or other high-velocity type injuries who might dissect a carotid artery, and those patients are typically young. Some of them come in and have strokes after they ve been in the hospital for a short amount of time, or some people come in with a stroke, and those people are also ones that we ve put carotid stents into. So I think this technology, although we feel like it s most appropriate for people with atherosclerotic disease, it does have other implications and other indications. I think it d be a good idea if we could break away to the next segment of the case, and we re going to sort of bring you along. What we ve got here is our sheath, and then, Jim, do you want to talk about the filter maybe? 00:25:00 JAMES LEFLER, MD: Yes, we have the the sheath, which is our platform to perform the carotid stent, with the sheath tip going all the way from the groin into the carotid artery below the stenosis. And then what we re doing now is we are trying to let some of the backflow of the blood so that we don t get clots up into the head. But then after that what we try and do is we try and pass a small wire -- which is a small filter wire that is collapsed on itself, which is the filter wire that Dr. Zwiebel showed -- through the area of stenosis and then distal to the area of stenosis. And then we open up the filter wire and use the filter wire for two reasons: one, to try and catch any sort of plaque as we perform the remainder of the procedure; and number two, as a guide for our balloon and stent to go into. 00:26:02 BRUCE ZWIEBEL, MD: I think, you know, one of the things we want to comment on is the operator s left hand is on the sheath. Now, that sheath is a cylindrical tube that s been introduced into the carotid artery already; that s what we had our wire showing on the previous set of pictures. So that is a direct line to the blockage, and this filter wire is now being introduced. And pretty soon we re going to see that that filter wire kind of snake through the blockage up into the brain. Here we see it right here, live footage of the It s now poking through, trying to we re negotiating it through that blockage. And here you see the tip of the wire coming up. And Jim, do you want to maybe take it through there? 00:26:45 JAMES LEFLER, MD: Yeah, the tip of the wire is actually in the distal internal carotid that has already been passed through the stenosis, and you can see the little dot right in the center of the screen with the that s on the that s on the filter wire. And then we are going to unsheathe the filter wire to deploy the filter basket so it will be able to catch any sort of

8 plaque that potentially gets dislodged. And there is a close-up magnetic view of the filter, and there it just got deployed. You can see the prongs of the filter wire just opened up. And now the filter wire is open, and the basket is open, and now we are in the next segment of trying to do this procedure. 00:27:33 BRUCE ZWIEBEL, MD: I think it d be a good idea there s a couple more questions that came through via , and many questions have been coming in about the symptoms of stroke. I think, maybe one of you two want to cover again what things people ought to be concerned about. 00:27:47 BRAD JOHNSON, MD: Yeah, we a lot of people come to see me about, you know, they ll pass out, or they ll be dizzy, and these are not the symptoms of stroke; they re pretty specific. We ve got to remember, what is occurring is a piece of plaque is breaking off and going into your brain. So, for instance, the right side of your brain controls the left side of your body, so what will happen when a piece breaks off, it s going to go up into your brain and cause the left side to either go completely paralyzed and you won t be able to move it, or it goes numb. And if you have a minor stroke, or TIA, then that s going to return to normal in an hour, a couple of hours, but that is a serious sign that you re going to have a major stroke. And then the other thing that can happen, if one little pi a tiny piece breaks off, it actually can go to the back of the eye, and people will tell you it feels like a grey shade got pulled over one eye. And it s never both; it s always just one. Because a lot of people come in, say, Well, I have blurry vision. Well, blurry vision isn t a sign of a piece breaking off and going into the into the back of the eye; it s usually just a grey shade being pulled over the eye. 00:28:48 BRUCE ZWIEBEL, MD: So I think that one of the main points, I think you ll both agree, is that if you have any of these TIA -- which you mentioned, which is transient ischemic attack, which is sort of want some people call a mini-stroke -- those are some of the greatest warning signs that you re at risk for having a major stroke. So if you have any of those type of symptoms that are fleeting, you know, if you have a paralysis or a numbness or a visual problem that comes and goes, then we would urge you to quickly go see a physician. That s a very serious problem. 00:29:18 BRAD JOHNSON, MD: Bruce, do you want me to show them the PowerPoint thing and we ll do that? 00:29:19 BRUCE ZWIEBEL, MD: Yeah, that d be good. Great. 00:29:21 BRAD JOHNSON, MD: One thing that has really, like Bruce mentioned, been a great investment, when we first started doing this at Tampa General, we didn t have a filter. And when pieces would break off, your stroke rate would go up. But you know, kind of thanks to the university and also Tampa General for allowing us to pursue this in the face of that, and also the companies, probably like Guiden [sp?], who developed these filters, because it s been a major advancement as far as protecting the brain when we do these procedures. So basically, the filter is collapsed down, taken across the artery of the narrowing of the artery, and then reopened. And as Jim will probably show you in the next slide, that artery up there where the filter is is completely normal, and all that disease is localized down to the bifurcation. And the thing we re going to do here soon, which is we re going to take a balloon and go in and open that lesion up, and that s going to allow us to place the stent through there safely because that filter that we have is a very fine wire, very tiny, and it can get through most of those lesions without any trouble. So I have to emphasize that this technology has been a major advancement which allows us to do this safely now, compared probably to five or six years ago.

9 00:30:30 BRUCE ZWIEBEL, MD: I think one of the other slides you have in the PowerPoint is with regard to predilating. We saw in the animation earlier that a balloon was placed before the stent to open up the plaque in order for us to introduce the stent, and I think some of the blockages are so tight that we can t even fit, you know, things as small as I was showing you earlier through them, so we have to what we call pre-dilate, open them up ahead of time so that we can have at least a conduit to introduce our stent. So let s break away. We ll get the next segment underway. We re kind of getting to the meat of the action, and we can talk about predilitation, Jim, and the stent. 00:31:10 JAMES LEFLER, MD: Yes, and this is centered over where we already have the filter wire in place, and we re passing a balloon over the wire, through the sheath, and then we re going to continue to advance this balloon up to where the area of narrowing is. And once we put the balloon across this area of narrowing, we re going to inflate the balloon to, as Dr. Zwiebel said, to try and create a conduit so we can deliver the stent across the lesion. And the reason why we do this is the stent delivery system is a lot thicker than the channel of which you are going to pass through the carotid artery, so that s in the area of stenosis -- so that s why it s important to predilate. And here it s good that we already have the filter wire in place because as we pre-dilate, some particles can break off and the filter wire basket will potentially capture some of those particles. And this is a this is us advancing the balloon, advancing the balloon in the groin. But remember, as we advance in the groin, we are watching the screen and watching the balloon cross the lesion. 00:32:23 BRUCE ZWIEBEL, MD: I think we can see it come up now. There s a marker. 00:32:25 JAMES LEFLER, MD: See it just track up now? And as it tracks up, we inflated it to get a good pre-dilatation to try before we placed the stent. 00:32:41 BRUCE ZWIEBEL, MD: You know, we ve been getting some questions, and I think this would be a good time to cover it, about how long does a stent last, does it collapse, things about the durability. Brad, you alluded to the durability of stents a little bit earlier. 00:32:55 BRAD JOHNSON, MD: Yeah, because a lot of patients will ask me. I work at the Veterans Hospital, too, and they re concerned because they ve had heart stents placed and they ve had two or three and they have to go back in and get it ballooned, or then they had the stent collapse down and they have to go to surgery. And that was the skepticism amongst surgeons in the beginning. We thought, Well, God, here we are, this thing s going to collapse down, and you know, we re going to have a lot of people having strokes. But it hasn t proven to be because the, like I mentioned, the carotid artery of the disease is very focal, and the rate of restenosis is five percent or less. And it s so easy to treat the restenosis: we don t operate on you, we don t remove the stent, we just put a balloon back up there and reopen the stent again, and that works perfect. And so, this location that, I guess, is the key to this and the fact that we just haven t had that many people come to surgery. I mean, probably one out of every 1,000 patients has had to have surgery after having a stent put in. 00:33:49 BRUCE ZWIEBEL, MD: Yeah, I think there s distribution of between it s a very high-flow area and, you alluded to, Brad, earlier that it s a very focal, very localized disease, so I think it s different than other parts of the body that we stent. I find I was almost chuckling to myself. There was a couple s that came through, and they were asking who actually does the procedure, which it actually is us in the video; we re not just doing the narration. And I think that brings up a good point that we have a multi-disciplinary team here at Tampa General, which we feel gives patients the best possible opportunity for the best

10 possible outcome. And by that I mean there are some surgeons some patients who are just poor candidates for surgery; there are others who are poor candidates for stenting. So you really need a program where you have the very best of both abilities, and I think that s what we have here at Tampa General. And just to supplement that just a little bit, there s a trial that s going on in the United States sponsored by the NIH called the CREST trial, and it s a trial where they re looking at randomizing patients for surgery versus stenting to actually see which is the best procedure, if there is a best procedure, and where is the surgery or where is the stent best used and what type of scenarios. Because we have both types of expertise here at this hospital, we ve been selected. We re one of a number of sites in the United States who have been selected for this trial, and we re enrolling patients whenever possible to try to gather that information. 00:35:28 BRAD JOHNSON, MD: Yeah, there s certain subsets of patients who we know stenting is better: people that have terrible heart disease or lung disease or who can t undergo an open operation, and people that have radiated necks. But then on the other hand, there are some people that probably should not get a stent. That s what the CREST trial is going to answer for us, it s going to determine which people, and so it s a very important trial because it s government-run, it has no bias. Another thing that Bruce mentioned, that we ve always worked here together. I m a vascular surgeon and interventional radiologist. We have a conference together once a week and we go through all these cases with a group of surgeons, maybe 8 or 10. We ve got residents and students, interventional radiologists, and we make decisions on a collective basis, and that way, you know, always 20 minds is better than one mind. And by doing that, that s, I think, been one of the major reasons that we ve been successful at Tampa General, along with the University of South Florida, in establishing programs like the carotid stent program and the endovascular AAA aneurysm program. 00:36:30 BRUCE ZWIEBEL, MD: This is actually a good segue. We ve been getting a number of questions about, you know, the filter s in place, now how do you get it out, and things like that, so I think what we ought to do here is maybe break to the next segment of the case. And just to bring you back up to speed on what we ve done so far, we ve got the filter wire up in the internal carotid artery, we ve got the balloon angioplasty to get the stent in place, and now we re actually introducing a stent. Jim, do you want to tell them 00:36:56 JAMES LEFLER, MD: And that s what we re focused on right there. The little gray square is the actual stent delivery system. We ve crossed the lesion with the stent in place, and we re about to deliver it. You can see my hand right there about to deliver the stent. Those two prongs on either side as I m sliding it back is delivering the stent and opening up the stent and laying it in the carotid artery, and what we re doing now is we re looking on the screen as it was deployed to make sure where it is and what location it is and how it was done. And now we re about ready to pull the stent delivery system out. But as you can see the stent delivery system track up -- this is before we deployed it, the little two dots there crossing the lesion. And there s the stent after it s deployed. You can see the metal the faint metal outline of the stent in front of those vertebral bodies. And you have distally where the wire is through the lesion and with the filter wire above the stent. 00:38:02 BRUCE ZWIEBEL, MD: I think at this point we re going to go back to some of the slides, and Brad, maybe you can help take people through some of the stent deployment. 00:38:10 BRAD JOHNSON, MD: Yeah. You know, first we had predilitation of the in order to get the stent in there. And then after that, as Jim just alluded to, we placed the stent across that lesion. And we try to cover -- we try to get into normal artery distally and normal artery proximally, and that stent opposed against the arterial wall and keeps plaque from breaking

11 off and going up into the brain. And then after we do that sometimes there s some residual narrowing. The stent has a radial force, as Bruce mentioned earlier, that it expands until it hits something, but then sometimes it s not strong enough to push that, you know, that calcific, hard plaque off. And so after that we ll come back in with a balloon and gently open stent up a little bit further so we have a good anatomical and physiological result from that. 00:39:02 BRUCE ZWIEBEL, MD: Just before we get further along, there have also been a number of questions about stroke, the use of medicines to dissolve clot in the brain, and there have been a couple of questions about stroke teams. I think it s important for us as a group here to comment that, you know, Tampa General is one of the few centers in the state that has complete stroke program. Jim, maybe you can talk about comprehensive stroke centers. 00:39:31 JAMES LEFLER, MD: Yes, as a neurointerventional radiologist, I deal with a lot of the vessels of the head, and Tampa General is one of those few centers in the state of Florida, as Dr. Zwiebel said 00:39:39 BRUCE ZWIEBEL, MD: How many are there? Do you know how many? 00:39:41 JAMES LEFLER, MD: I think there s three other comprehensive stroke centers in the entire state of Florida, but those comprehensive stroke centers have to meet very specific criteria on having certain people on staff to make sure that if someone does come in with a stroke that it can be treated at an appropriate time and at an appropriate level. And that s another reason why it s somewhat good to have procedure done here at Tampa General, for the main reason that 00:40:10 BRAD JOHNSON, MD: What time period do they have, Jim? 00:40:11 JAMES LEFLER, MD: Usually for an acute stroke in the front circulation of the brain, called the anterior circulation, you have up to six hours. Really, it s up to three hours for intravenous tissue plasminogen inactivator, which is the clot-busting drug, and up to six hours to try and give it through the arteries of the neck and head from a groin access, sort of how we re doing the carotid stent. We have a very excellent stroke service at Tampa General that does cover a lot of the acute strokes that do come in, and we have all the devices at Tampa General necessary to try and open up vessels inside the head, some of which are FDA-approved and some of which are not. However, we try and appropriately treat those patients that come in with an acute stroke in the appropriate manner that they need to be treated. 00:41:06 BRUCE ZWIEBEL, MD: I think it s probably worthwhile to mention that we ve been talking today about carotid artery disease. That s one element of stroke. As Brad showed the slide earlier, maybe 10%, 20%, 30%, maybe 25% of strokes occur as a result of carotid disease, but really, stroke, carotid disease, is all lumped into a big category of neurovascular care. And I think, you know, one of the things here at Tampa General is, again, it highlights the multidisciplinary nature of disease treatment, which really is not something that s available in every hospital. And Brad, I know you talked about it a little bit about our interaction, but I think, you know, globally that s an important thing. When patients come in to me, I think it s very important to have the resources of multiple different departments and expertise across the board. 00:41:51 BRAD JOHNSON, MD: Yeah, and I think it keeps you honest, too, because you re not by yourself working; you re working as a group. And groups, especially surgeons in radiology, can be pretty critical of each other. And so, you know, if you if you re doing something that people don t believe is right or isn t good for the patient, there s usually somebody that

12 will tell you to do it another way or you re doing it that wrong way. And so, that s you know, that s been good. Plus, we re, you know, we re with a university system here and the University of South Florida, and therefore, we re always checking our results. We publish papers on this. And our chief of vascular surgery here is the editor of the endovascular journal. And so you have a lot of expertise here. It surprises people when I tell them, By the way, the editor of the vascular journal is in Tampa at the University of South Florida and at Tampa General Hospital, because people just don t realize that exists in this town. 00:42:47 BRUCE ZWIEBEL, MD: I think that s a really good point. For me personally, I ve been here 15 years, and you know, to think we ve probably done more carotid stenting here at Tampa General than just about any institution in the state, maybe one or two have done more or about the same. So, and I think if you look at our results, it s something to be proud of. And people here in Tampa, maybe people here in the state of Florida, might not realize the resource of, you know, and the value that comes with having this multidisciplinary approach. Just to jump ahead, there s been a couple of questions. Matter of fact, on the same topic, which is I guess there are some people out in the audience who know that they have blockages above the point we re talking about. So in other words, most carotid artery disease occurs at the branch point of the main carotid artery. There are some people who are ing questions that they -- with a fair amount of sophisticated knowledge that there s blockages higher up in their artery at the skull base in their brain. Jim, you maybe want to comment on some of that? 00:43:55 JAMES LEFLER, MD: Yeah, since I treat a lot of the head and neck vessels, basically you can have stenosis higher up in the head vessels, although it is somewhat different than the neck vessels. If you do have stenosis or narrowing in those head vessels, some can be amenable to medical therapy, some can be amenable to using a balloon or angioplasty, and some can be amenable to using a small, low-profile stent that is different than the stent that we re talking about today, but these lesions can be treated by endovascular as well as medical. And then one thing about Tampa General that we have is we have a very good neurosurgical team that if stenting or medical therapy fails and it needs to be still fixed or if the vessel is occluded, sometimes the neurosurgical team can do a bypass that will help get more blood supply to the brain. But these are only in indicated patients, and that s the good thing about our hospital is that we all work as a team and we try and figure out what procedure is best for what patient. And those vessels of the head are a little bit more special because the risks of stenting or angioplasty or doing anything when you get higher up in the head go significantly higher. 00:45:19 BRAD JOHNSON, MD: Yeah, there s only, what, three or four places in Florida that do stenting in the brain? 00:45:22 JAMES LEFLER, MD: There s very there s just there s only three other places in the state of Florida that usually do the degree of endovascular stenting of the head vessels that Tampa General does, or more specifically that I do, but. 00:45:34 BRUCE ZWIEBEL, MD: I think it d be a great opportunity for us to break into the next segment of the case. And right now, I guess, we ve dropped off the stent. We deployed it as before, and now we re picking it up. Jim, why don t you take us through. 00:45:48 JAMES LEFLER, MD: Yeah. Here we re the next, the next process after deploying the stent, as Dr. Johnson had alluded to, was sometimes the stent doesn t have enough radial force to open that vessel up completely. So what we try and do after the stent has been deployed is to try and get the stent fully opposed to the wall where the area of narrowing is and try and open up that vessel to a better extent than the stent has the ability to, and it s called post-

13 dilitation, and we usually use a very trackable balloon that rails over the stent or, I m sorry, rails over the filter wire that is still in place. And you can see Dr. Zwiebel here advancing it over the wire. As we re watching the screen, we re holding the wire, or pinning the wire in place, and driving the balloon up across the lesion that has the stent already in place, and we re going to navigate that balloon, or watch that balloon go across that lesion. And this is an insufflator device that we use to open up the balloon. You can see that the dial is going to turn in a clockwise direction as we turn down on the on the insufflator and inflate the balloon. We do it very slowly because you don t want to all of a sudden jam a balloon in a place that it doesn t need to be. And there you can see the balloon within the stent. It s already opened up the bottom edge of the stent where it had that stenosis and reestablished flow, and then we quickly pull the pressure down off the balloon and then remove the balloon out of the body while still holding the filter wire in place. And the important point here is that the filter wire is still up, and any debris that could have been deploy washed out would have hopefully been caught by the filter wire. 00:47:45 BRUCE ZWIEBEL, MD: That brings up a good point. Now that we ve seen the stent deployed and we ve wallpapered it up against the wall, if you will, a couple of questions came up by . Brad, you might want to talk about this. Now that the stent s in place, can it move? If I turn my head, if I You know, there s been a bunch of scenarios depicted, maybe you can comment on 00:48:07 BRAD JOHNSON, MD: Yeah, usually the nice things about these stents and the newer technology -- and that s the reason that if you look at some of the initial studies with placing stents, and we were involved in them, the technology, as one of my former professors says, You know, you re working with a medieval instrument here. And we ve finally come into modern times. And these stents are going to keep expanding until they oppose a wall, so we I ve not say never, because never, something always happens, but most of the time these stents, they just don t move. And you can turn your head, you can get in a car wreck, you can get hit playing football or something, and the stent will stay in the same place. So that hasn t been of any concern for us. 00:48:46 BRUCE ZWIEBEL, MD: A couple other good questions came through that I think we need to cover is some patients out there are talking about they ve had coronary stents placed, stents placed in the heart, and they have known high cholesterol and other risk factors for disease. Again, either one of you want to comment about, you know, they ve been asking, Well, what s my risk of having carotid artery disease? 00:49:13 BRAD JOHNSON, MD: Yeah, they correlate. You know, when I m teaching students and residents, I tell them, What s the most statistically significant thing about it when you have a little brup when you can hear a little noise in the carotid artery? Well, the most important thing about that is that means if you had a 30% chance of having significant disease in your heart blood vessels. So, same kind of thing works with coronary, with heart vessels. If you have heart vessel disease, then you should have a duplex scan of your carotid artery in order to see if you ve got disease there. And so, there s these people of high risk, these people with hypertension and these people with high cholesterol and stuff, those people really need to be screened with carotid duplex scans or ultrasounds, same thing, in order to determine if what degree of stenosis they have. 00:50:00 BRUCE ZWIEBEL, MD: And I think, you know, that you mentioned screening. It brings up a very good point because there s a number of ways to get screened there today out there today: there s trucks that come into neighborhoods that screen, there s all sorts of things you can have at the mall. I think my personal feeling is, and it s easy for us to say sitting