Peripheral Arterial Disease

Rotational Excisional Atherectomy With the Rotarex™ Atherectomy Device

Miguel Montero-Baker, MD

Associate Professor of Surgery, Division of Vascular Surgery and Endovascular Therapy, Baylor College of Medicine; Associate Clinical Chief, Division of Vascular Surgery and Endovascular Therapy, Baylor St. Luke’s Medical Center, Houston, Texas.

Miguel Montero-Baker, MD

Associate Professor of Surgery, Division of Vascular Surgery and Endovascular Therapy, Baylor College of Medicine; Associate Clinical Chief, Division of Vascular Surgery and Endovascular Therapy, Baylor St. Luke’s Medical Center, Houston, Texas.

Can you tell us about your practice?

I am a vascular surgeon and call myself a “hybrid model”, because I am part of a younger generation of vascular surgeons who chose to train in both open and endovascular surgery. I did my subspecialty training in Leipzig, Germany, with the founders of the globally renowned Leipzig Interventional Course (LINC). For three years in Leipzig, I put the scalpel aside and pursued catheter-based technologies. Today I am an associate professor of vascular surgery at Baylor College of Medicine in Houston, Texas, and lead the programs for limb salvage. 

We have a balanced approach, where there is a time and a place for catheter-based technologies, but also a time and a place for open surgery. My practice here for the last five years has been focused on limb salvage. It was a huge area that had been uncared for. It had been fractioned amongst multiple specialties and had not yet been an organized approach. We have built a program that starts from the ground up, providing all sorts of noninvasive vascular lab workups and includes the management of wounds with podiatry and wound care that work for vascular surgery. Vascular care is provided when need be, whether it is endovascular, open, or a hybridization of both procedures. We do anywhere from 30 up to 70 procedures in a week with a team of 4 vascular surgeons, 2 podiatrists, and 3 nurse practitioners. 

How has Covid-19 affected your program?

Covid has been an interesting turn of events in Texas. We experienced a very quick halt to procedures in an effort to flatten the curve. Eventually, that pause on procedures would bring us an explosion of procedures. First, the city and/or the state decided to reopen, including elective surgeries, as long as the hospital capacity was adequate. During the pause on elective procedures, we continued to care for patients that required emergency procedures, but attempted to divert a lot of these cases that didn’t need acute intervention. Now we have a second wave that actually is a tsunami. You have probably heard that Texas has been hit hard, and it is true. We are going about our normal, regular day, but now have the addition of an overwhelming amount of patients with Covid. Covid has been identified as a very coagulopathic disease, meaning it is quite prone to create thrombus and clots. Who cleans out and clears clots? It is usually the vascular practitioners and particularly, vascular surgeons. We are experiencing our normal volume as a busy practice that deals with limb salvage and we are also now spreading ourselves thin in dealing with the collateral damage of Covid. Some patients develop clots simply because Covid is a prothrombotic condition. Some patients’ debut with Covid is not a respiratory problem, but a clotting problem. On the other hand, those patients that are extremely sick with Covid, those with respiratory problems who have become tied to machines, now have different devices and cannulas in their bloodstream helping to keep them alive. Those cannulas then go on to create clotting and clotting-related problems. It has been a tough time for us all. Team members have gotten Covid, we have people that are quarantined because they are at high risk of exposure based on their contact with a patient that we didn’t know had Covid, and we are all participating in more call than usual. At the end of the day, however, I am proud to say that we have done a significant amount of good work and I hope that our community will be better because of it. 

What are some of the challenges you see in treating peripheral arterial disease?

We are facing a change in demographics that is very clear. We are moving away from what I call the “Marlboro anatomy”, which is heavy smokers who are now elderly, have smoked an incredible amount in their lifetimes, and have large artery disease, meaning we see that disease mostly in the aorta and the iliac arteries. Obviously, people still smoke, but now we are dealing more with diabetes, obesity, and renal failure, and these three conditions affect, interestingly enough, a different anatomy, mostly attacking the smaller vessels. Instead of causing disease in the aorta or the iliac arteries, the disease we are seeing actually extends all the way down to the tibials, to arteries below the knee, and arteries below the ankle. It is very extensive and heterogeneous disease, with different types of lesions, featuring combinations of clots, plaque, and calcium. This type of multilevel disease is currently our focus in investigations and in attempts to find better solutions, because it doesn’t matter how good of an open surgeon you are, certain vessels cannot be bypassed. It also doesn’t matter how good of a endovascular therapist you are — there are certain lesions and morphologies that are just harder to treat than your average run-of-the-mill peripheral arterial disease plaque.

What has been your experience in working with the Rotarex Atherectomy Device?

In 2006, during my endovascular fellowship in Leipzig, is when I had my first exposure to the Rotarex Device (BD). I used it on a daily basis; not once, but multiple times in a day. It was probably one of the first iterations, but it was obvious even in 2006 that there was a space for this device. Obviously, there was going to be some technological growth. Now, 14 years later, we have seen, thankfully, the market penetration of the Rotarex Device, which had been excluded from the American physician’s toolbox for so many years, but is now, finally, here for us to use. I have had the delight of holding the latest iteration in my hands in the last few weeks. The newest generation of the Rotarex shows remarkable improvement in its ease of operation, as well as in its efficiency in the removal both of clot debris and plaque.

The Rotarex Atherectomy Device is described as “rotational excisional”. Can you explain what that means?

In the U.S., we tend to try to fit devices into these very particular boxes of “Oh, this is a plaque cutter.” Or “Oh, this is just a ‘X’ or this is a ‘Y’ device.” However, the Rotarex Device has a degree of heterogeneous action, not only because it does rotate and it does use an internal Archimedes’ screw system to extract and remove, but it is also a side opening device. The mouth of this device is not in the front, but the tip has a large-bore, very efficient cutting hole on the side that exposes the Archimedes’ screw system and an internal cutter. This rotational system engages the side wall of the artery during the entire time that you are advancing. Instead of trying to go with a frontal device, which could be limiting due to size, you create a large wall on the side of the device, and now have a very efficient way to actually engage whatever material you are trying to extract. The Rotarex System is highly efficient in removing thrombus, but it has also shown to be very efficient with plaque removal. Its ability to cut in such an efficient way is paired with the Archimedes’ screw system, which spins fast enough to create negative pressure and extract debris. Once debris is aspirated into the side port, it is further broken down by the internal cutter, until everything is extracted through the sheath and into a collecting bag that comes with the system.

How does the action of the Rotarex compare to other types of atherectomy? 

There are two aspects of the Rotarex Device that shine. First, it has very efficient clot removal. For thrombectomy purposes, I think this device is great. Second, the Rotarex Device engages plaque in a very efficient way. If you are considering doing a thrombectomy procedure, there is a gamut of devices designed for clot removal, but these devices are not able to engage plaque. Or, a device may allow you to engage plaque, but doesn’t have the ability to remove clots. We know now from multiple clinical studies that most complex plaque burden is a combination of some chronic clots and some organized plaque, so you never really have just one or the other morphology. There will always be a combination of both of these entities. Another other important aspect is the Rotarex Device’s ease of operation and installment. You are not limited to particularly ultra-low profile wires, as is the case with many other devices requiring the use of wires that are very flimsy and are not made to do an intervention. The Rotarex Device has a very nice .018-inch profile wire. After you are finished with atherectomy, you can use that wire to continue with stenting or balloon angioplasty, or whatever you need to do, which increases efficiency and it certainly helps to obtain the results that you are seeking. The Rotarex Device also has 2 sizes available, a 6 and an 8 French (Fr). For the 6 Fr device, the IFU allows its use down to 3 mm vessels, so you can do some rather aggressive proximal tibial work even in addition to femoropopliteal interventions  with the 6 Fr device. The 8 Fr device allows you to tackle some very aggressive, long, complex lesions with a lot of material in them, because of the efficiency of the mouth. Now you have an 8 Fr large side mouth that engages in an efficient manner to help remove a significant amount of debris. 

Is there a typical case for use of the Rotarex Device?

I really think it has a fairly broad reach. One of our latest cases was a complex chronic total occlusion (CTO), a long occlusion of the superficial femoral and popliteal arteries. After just one pass of the device, the amount of debulking that we had was so efficient that we were able to treat a long, complex lesion without having to stent. Even a few years ago, it is the sort of lesion that usually I would end up stenting, because of how complex it would initially seem. The Rotarex carries its weight through a good amount of the disease pattern we typically see, from a relatively simple to a relatively complex lesion, and it helps to obtain a good result. 

Do you have advice for operators interested in trying this device?

For those of you that do atherectomy on a regular basis, you will already be amply trained and able to pick up this device with the advice of a company clinical expert in your cath lab. BD has always been committed to education. Certainly there will be a few of us out there that have the clinical experience and who will be available in case people need help. For those of you that don’t necessarily have any experience with regular atherectomy use, there is that commitment from BD to create opportunities for growth and education. In the Covid era, it is going to be hard to have a face-to-face meeting, but we have set forth a program for digital education that will include webinars and live cases on Webex calls in the next few months. People will be able to log in and share questions with me and maybe other operators. I know that BD is working on a digitally available program where people can call us from an iPad, laptop, or an iPhone, see some of the cases that we have done, and even participate in a live case discussion.

You mentioned that seeing a mixed plaque morphology, with both thrombus and some calcified plaque, is a common scenario in PAD. How does the Rotarex Device affect these cases? 

Mixed morphology plaque is seen in the more complex lesions. We know that there is usually a core lesion. Let’s say you have a case where the superficial femoral artery (SFA) measures 40 cm. It is usually the distal third of the SFA that experiences plaque accumulation. It is an area of torsion, rotation, extension, and flexion that creates forces leading to a more robust plaque formation in this location. Soon that plaque starts extending cranially and caudally. Eventually, when the lesion gets to a point where it may be limiting flow, what happens is the same pathophysiology of a heart attack. Either there is erosion of the endothelium, where the plaque creates a clot or the flow of blood through that area is so limited that the blood flow is stagnant, and that also can create a clot. You can have extension of that clot both caudally and cranially, which cannot necessarily be identified by non-invasive imaging such as ultrasound. When you do an angiogram and are committed to treat, only now is this long lesion visible. Within that 40 cm of the SFA, let’s say there is 15 to 20 cm of occlusion. Via angiography alone, there is no way you can tell what is inside that occlusion. We know from scientific research, however, that it will be a combined process of both plaque, atheroma, cholesterol deposition, and the acute clot formation both on the tail end and the front end. When you use a device such as the Rotarex System, that is efficient in removing all types of thrombus and plaque, once you do 1 or 2 passes, you can identify the culprit lesion. It might be that maybe 5 cm on the top and maybe 5 cm in the bottom were actually just clots and the artery looks fairly normal overall, with perhaps only a small area of plaque burden that may require more atherectomy, balloon angioplasty, and then maybe stenting. You are able to limit your intervention to a short segment of the artery and not 40 cm of the artery, which is more commonly what we end up doing nowadays. Use of the Rotarex Device in this scenario is important, because it allows us to uncover the true length and complexity of the original culprit lesion that led to such a long occlusion. We don’t have to stack the artery with a bunch of stents, thinking that it is a huge lesion, when actually it is a shorter lesion than expected. There is a great deal of excitement coming from that realization. 

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Case Report

This is a 62-year-old male with a past medical history of diabetes mellitus type 2, chronic kidney disease, and hypertension. He was referred to the emergency department with a diagnosis of 2-month diabetic left foot infection that progressed to extensive gangrenous changes. PMSx (pulse motor sensory) assessment revealed peripheral arterial disease/loss of toes. Vascular labs demonstrated a very low ankle-brachial index with an occlusion of the superficial femoral artery (Figure 1). Wound, Ischemia, and foot Infection (WIfI) class was W3/I3/FI2 (stage 4 risk). The patient was taken initially by podiatry for source control, followed by endovascular revascularization. The occlusion was crossed intraluminally via a retrograde approach and the guidewire was recovered into the antegrade angled support catheter (Figure 2). Once across the occlusion, we performed atherectomy with the Rotarex Rotational Excisional Atherectomy System over the included Rotarex .018-inch hydrophilic angled guidewire (Figure 3). We achieved significant luminal gain after only a single pass with the Rotarex device (Figure 4). The debulked occlusion was subsequently dilated with adjunctive therapy, resulting in good femoropopliteal perfusion and distal run-off with no signs of distal embolization (Figure 5). Figure 6 denotes the clinical course of the patient, from source control, to granulation, to skin grafting. 

This article is supported by BD.

Disclosure: Dr. Montero-Baker reports a consulting agreement with BD.

Dr. Miguel Montero-Baker can be contacted via Joanna Starosolska at joanna.starosolska@bcm.edu
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Rotarex™ Rotational Excisional Atherectomy System Safety and Risk Information: The Straub Endovascular System is herein referred to as the BD Rotarex™ Rotational Excisional Atherectomy System. Indication For Use: When operated with a Rotarex™ single use catheter, the Straub Endovascular System is intended for use as an atherectomy device and to break up and remove thrombus from upper and lower extremity peripheral arteries. It is not intended for use in coronary, carotid, pulmonary, iliac or renal vasculature. Contraindications: Use of the Rotarex™ family of catheters is contraindicated in the following situations and locations: · In the cardiopulmonary, coronary, cerebral, iliac and renal vasculature · In the venous vasculature · In instances of persistent vasospasm · In patients not suitable for atherectomy/ thrombectomy · In patients with known or suspected allergies to any component of the Straub Endovascular System · In patients with hemodynamic instability, shock or severe coagulatory disorders · In patients where it is impossible to achieve sufficient anticoagulation and platelet aggregation inhibition · In areas of known or suspected infection, especially at the puncture site or target vessel segment · In vessels which are oversized or undersized for the particular Rotarex™ catheter used · In stents, stent grafts or bypass grafts · Without the use of a Straub provided guidewire · When the Straub provided guidewire cannot completely cross the target lesion · Where the Straub provided guidewire is in a subintimal position of any length · Where the Straub provided guidewire has become threaded or entangled in the wire mesh of a stent, stent graft or the lining of a stent graft · Where the target lesion is located in a region of marked vessel tortuosity (has a radius of curvature ≤2 cm) or is heavily calcified · Where pre-existing damage is present in the vessel wall at or near the target lesion from prior surgery, aneurysms or other disease · During MRI procedures or where electrical current may be passed to an undesired location via the catheter, e.g., during electrocautery, electrosurgery or defibrillation. The Rotarex™ catheter and guidewire must be entirely removed before these therapies are administered, even in an emergency situation · Where the recommended separation distances from Radio Frequency and Electro-Magnetic Interference (EMI) sources cannot be maintained (Reference the manual for the Drive System) · Where any component of the Straub Rotarex™ Endovascular System has sustained damage, including any breech of the sterile barrier. Please consult package insert for more detailed safety information and instructions for use. © 2020 BD. BD, the BD logo, and Rotarex are property of Becton, Dickinson and Company or its affiliate. BD-20413

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