Cover Story

The Future of Vascular Intervention

New technologies, growing interest propel dramatic growth in interventional treatment of vascular diseases.

The field of vascular intervention is evolving at a rapid pace. The use of catheter-based vascular interventions for the treatment of aortic, carotid, cerebrovascular, peripheral and other diseases continues to grow as a result of new technologies, an aging population and cross-specialty interest.

Now, more than ever before, interventional cardiologist involvement in the treatment of vascular diseases is increasing. Cardiology Today’s Intervention and Chief Medical Editor Deepak L. Bhatt, MD, MPH, gathered leading experts in the field to capture their thoughts on the present and future state of vascular intervention. The following discussion features perspective from Daniel Clair, MD; Michael R. Jaff, DO; Barry T. Katzen, MD; Nicolas W. Shammas, MD, MS; Christopher J. White, MD; and Mark Wholey, MD, on evolving technologies and techniques, multidisciplinary collaborations and challenges ahead.

Dr. Bhatt: Where do you see the field of vascular intervention going in the next 5 years?

White: In my mind, vascular intervention encompasses everything from the tip of the head to the tip of the toes. The field of percutaneous nonsurgical revascularization will continue to expand as new technologies replace invasive open surgeries. In every place we see open surgery being done today, tomorrow it will become less invasive, more endovascular.

Wholey: I anticipate dramatic growth in vascular interventions for the comprehensive CV system in all compartments except the coronary. An increasing number of interventional cardiologists are becoming involved in treatment of the entire CV system, not just the heart. Without question, treatment of peripheral artery disease has seen a significant increase by skilled interventionalists.

Deepak L. Bhatt
Shammas: Looking at the exponential growth in PAD treatment that has happened during the last 10 years, I suspect this is just the beginning. This is in contrast to the cardiac field, where there has been a decline in the number of procedures, almost 30% over the past few years.

I do both coronary and peripheral vascular work. My practice is divided almost 50/50 by peripheral vs. coronary disease. At one point, the peripheral vascular work was only about 20%. Over the past 5 years, it has increased to about 50%.

Cover illustration © Lisa Clark

Katzen: I view endovascular therapy in the broadest sense possible: anything that is treated through a blood vessel. One reason for the growth we are seeing is the aging population with atherosclerosis, aneurysm diseases and valvular diseases. Many resources and research initiatives are being made toward improved technologies in the less-invasive therapy movement for these patients.

Clair: What we are seeing now, and what we will continue to see more of, is increasing interaction between all of the specialties involved in the treatment of patients with vascular diseases.

Jaff: The onus is on us, as physicians, investigators, industry representatives and inventors, to prove that the therapies we currently apply to our patients actually matter — from a quality standpoint, from a cost standpoint, from an efficiency endpoint. There is a great deal of interest in the most effective technologies for vascular diseases, whether they are next-generation drug-device products, bioresorbable drug combination products, combinations of catheter-based intervention with an exercise program, or hybrid surgical and endovascular cases.

Dr. Bhatt: What areas in vascular intervention interest you most right now?

PAD and CLI

Katzen: Interventional treatment of PAD and critical limb ischemia (CLI) seems to be increasing at an epidemic proportion.

Shammas: PAD is highly prevalent but underserved worldwide. There continues to be a lot of interest in lower-extremity intervention, in particular. We now have many tools available to treat patients with lower-extremity PAD. Treatment of the femoropopliteal segment accounts for about 30% to 40% of all lower-extremity interventions performed.

Wholey: More participants, especially cardiologists, are now involved with PAD and CLI interventions. The CLI results have been dramatic, especially in the infratibial vessels where both antegrade and retrograde access have opened up improved methods for recanalization.

I anticipate that the drug-coated balloons (DCBs) will have a major impact. The first DCB (Lutonix 035 Drug-Coated Balloon PTA Catheter, Bard/Lutonix) for patients with PAD was approved for use in the United States in October 2014 and the second (IN.PACT Admiral DCB, Medtronic) was approved in January 2015. Current research is now investigating a more efficient delivery system with controlled elution that will allow a higher tissue concentration over a longer period of time than the existing balloons.

Jaff: The combination of atherectomy and DCBs is an area of particular interest. Does it make a greater difference if you remove the plaque burden before delivering the drug via a balloon? Hopefully the answer will come in the near future.

For CLI, I think we will learn over the next 5 years the best initial strategy for patients. Results of the BEST-CLI trial and other ongoing industry-sponsored trials will hopefully provide the answers we need to treat these difficult patients.

White: I believe this area will become almost totally endovascular-based due to the new catheter-based technologies available and others on the horizon. Right now, about 20% of vascular procedures are surgical.

Christopher J. White

The techniques are drastically evolving. In the coronary, chronic total occlusions remain a persistent challenge. During the last 5 years, there has been an emergence of operators who are so technically skilled that they can cross virtually any coronary CTO. These techniques are now being used in the lower extremities. Below-the-knee vessels are the size of those in the coronary. What has limited us in the past when treating below-the-knee vessels has been long total occlusions. But the recent cross-fertilization of the CTO concepts from the heart have been brought down to the legs. Three years ago, we might have told a patient that he would lose his foot; today, we are applying CTO techniques and are saving limbs.

That is the beauty of the interventional cardiologist being in the heart and the peripheral arteries. You can say, “This worked for me in the right coronary artery, maybe it will work for me in the tibial artery.” More often than not, it does work.

Acute Stroke

Mark Wholey

Wholey: Of 800,000 acute strokes that occur annually in the United States and another 800,000 in Europe and Japan — roughly 2 million strokes per year — less than 5% are treated. With the introduction of the new retriever devices, stroke outcomes have been significantly improved with as high as 50% functional outcomes. With that, we are seeing dramatic changes, as noted in the current trials that included SWIFT PRIME, MR CLEAN and ESCAPE. Speed from the time of onset to the hospital is the critical element. There is a clear need for more interventionalists to be involved in acute stroke intervention.

White: At Ochsner Heart and Vascular Institute in New Orleans, cardiologists have been performing interventional acute stroke therapy for years, but we have done it with tools that were not well-suited to the task. Now, newer tools like stent retrievers (Solitaire, Covidien; Merci Retriever, Concentric Medical) are available for use. The small, flexible devices retrieve clots with stents that are attached at the end of a wire. It is a basket retriever, but looks like a stent. It is easier to manipulate than a coronary stent. In my opinion, cardiologists with carotid stent experience are extremely well-suited for acute stroke intervention.

There is a manpower shortage in the United States for the treatment of acute stroke. At our center, the reason interventional cardiologists started treating acute stroke was because we were invited by our neurologists. There was one neuroradiologist who couldn’t be on call 365 days a year. So the interventional cardiologists were asked to alternate coverage. Four U.S. states do not have any neuroradiologists. There are many places in the United States with more interventional cardiologists who can do this work. As cardiologists, we are members of a team led by a neurologist; I’m just the plumber. The decisions in acute stroke care are provided by the neurologist. But, if you ask me whether I can safely and effectively open the artery causing the stroke, the answer is yes.

Pulmonary Embolism and Venous Disease

Jaff: Pulmonary embolism intervention is changing in a number of ways. There are new data on specific regimens of thrombolytic therapies and how it should be administered. There are also new devices that have proven in studies to be very effective, such as the EkoSonic Endovascular System (EKOS Corp.) for ultrasound-guided catheter-directed thrombolysis.

The development of a team-based approach to pulmonary emboli is also gaining traction. There is a lot of interest in taking very complicated patients, in whom we don’t have a lot of support from the literature on what is best to do, and bringing together experts around the virtual bedside of the patient to make a combined decision. We have been using the multidisciplinary Pulmonary Embolism Response Team (PERT) at Massachusetts General Hospital to improve the care of patients with pulmonary embolism. It has been a huge advance in the management of patients with pulmonary embolism, leading to incredibly accurate and fast ways to make a diagnosis. A consortium at Massachusetts General Hospital in 2015 brought together 40 other centers that are interested in learning how to put together a PERT program. Response teams could also be considered for the treatment and management of other vascular conditions as well.

Shammas: Looking at the recent interest of cardiologists with the venous system, there is no question that this will be a rapid area of growth, specifically acute treatment of proximal deep vein thrombosis and massive or submassive pulmonary embolism using pharmaco-mechanical means. Chronic treatment in the venous world will comprise symptomatic superficial venous disease, especially patients with advanced symptoms like venous ulcerations and major hyperpigmentation.

Carotid Artery Revascularization

White: Carotid artery revascularization has garnered a lot of interest recently. With improved embolic protection devices and an evidence-based reimbursement strategy, I think stenting will emerge as the dominant therapy in the next 5 years.

Katzen: I anticipate a significant change in the greater use of carotid artery stenting. I think the trial data will support that. We went through a low trough in the case of carotid stenting because of the regulatory situation and multiple disciplines that don’t agree with each other, which has created a unique political environment.

Wholey: If we ever get reimbursement with a broadened indication from CMS, we will likely see a reactivation of carotid stenting. This area was lively for many years, but in the absence of any reimbursement there has been very little research lately.

Renal Denervation

Barry T. Katzen
Katzen: On a longer time scale, I believe that catheter-based renal denervation will become an important therapy for a variety of conditions including treatment-resistant hypertension, arrhythmia disorders, HF and so on. Although longer-term data from the SYMPLICITY HTN-3 (Symplicity, Medtronic) trial showed no significant difference between renal denervation and a sham procedure in patients with resistant hypertension, other trials are underway such as the SPYRAL HTN program of renal denervation (Symplicity Spyral and G3, Medtronic) in patients with uncontrolled hypertension, the SYMPLICITY AF study of renal denervation (Symplicity Spyral and G3, Medtronic) and pulmonary vein isolation in patients with paroxysmal and persistent atrial fibrillation, and the REDUCE-HTN: REINFORCE study (Vessix, Boston Scientific) in patients with hypertension.

Abdominal Aortic Aneurysm

Daniel Clair
Clair: Technology for the treatment of abdominal aortic aneurysms (AAA) has been around and commercially available in the United States since 2000, when the first devices were approved. The follow-up remains fairly similar, which is intensive for patients who have endovascular treatment. That exposes all of the patients to a fair amount of risk. It is another area where there will be increasing scrutiny on what the most cost-effective treatment is. Recent research on endovascular AAA treatment showed reintervention rates at 2 years of about 10% to 12%, but that is likely a significant underestimate of the number of people who are having problems. The real problems begin from year 3 and beyond. In several study series, the risk for aneurysm rupture ranges from 1% to 5% within the first 2 to 5 years. That is a significant potential rupture rate compared with open surgical repair. Right now, we have a solution that is less morbid and less mortal early on — endovascular treatment — but we don’t know whether it is improving long-term survival and it may be increasing risk related to aneurysm rupture down the road. We need to see some improvements in the long-term outcomes of endografting for AAA repair. I think that ultimately will come from alternate strategies, not reiterations of current devices.

Other Areas of Interest

Katzen: On the aortic side, there is also interest in the integration of valves and grafts. Certain areas that have been off-limit zones now represent exciting areas for the future including treatment of the ascending aorta, transverse aorta and branch endografts.

Clair: Right now, many operators performing interventions are exposed to radiation at fairly high doses over extended periods of time, exposing them to a significant amount of risk. There needs to be a way to provide guidance without exposing the individual to fluoroscopy radiation. That is a very important step.

Shammas: Embolic protection is being studied with transcatheter aortic valve replacement and also with PAD treatment. Data show that embolization occurs frequently during the treatment of PAD. There are certain subsets of patients who would benefit the most, such as those with the highest risk for embolization, CTOs, thrombotic occlusions and very long irregular calcified disease. However, use of embolic protection is inconsistent; many operators do not use it, while others use it in all cases. If we can pin down the highest-risk patients and apply these technologies, we will be practicing more cost-effective medicine.

Bioabsorbable stents have been tested in the coronaries and are awaiting approval. This technology could also be taken to the peripheral vascular bed. Having a drug-eluting bioabsorbable stent in the periphery that does its job and disappears after a while would be great.

Another area of interest is pharmacologic and lifestyle interventions. A conservative approach — quitting smoking, routine exercise, controlled risk factors — can be very powerful. I think we need more emphasis on pharmacotherapy and lifestyle interventions in certain patients.

Dr. Bhatt: What may we be doing in the near future that we are not doing today?

Michael R. Jaff

Jaff: I don’t think we will be intervening on asymptomatic patients. That came across loud and clear at the July 2015 CMS MEDCAC meeting. I anticipate more attention on trying to increase the medical management of the asymptomatic patient, making sure those patients get the same degree of risk factor interventions as do coronary patients.

Clair: Given long-term data on exercise therapy for claudication with infrainguinal disease, we should increase use of that therapy in patients. It is incredibly inexpensive; in every study that has analyzed it over extended periods of time, the outcomes of interventions are similar in terms of walking improvement and risks to the patient are minimal. In the CLEVER study, exercise therapy had similar outcomes to interventional therapy in patients with aortoiliac occlusive disease. In my mind, until something changes with the outcomes of interventional therapies that radically shifts the needle, we will see many more claudicant patients treated with exercise therapy rather than interventional therapies.

Dr. Bhatt: What procedures are we doing today that might not always be at the forefront of care?

White: Antegrade punctures may go away in the near future. This is done because the catheter lengths aren’t adequate. We need longer catheters to get to the foot, for example. Instead of using contralateral femoral artery access, we take the shortcut with an ipsilateral antegrade approach, which has a higher risk for complications and bleeding. I think the future will be radial access with much longer catheters. We will be using radial access to treat lesions below the knee. Femoral antegrade punctures will be replaced by longer catheters from safer access points.

Clair: We will be looking at ways to reduce the cost of vessel preparation and medicated therapies for any vessel treatment that we do.

Nicolas W. Shammas

Shammas: If you look at the data, we have a very aggressive approach to stenting. About 60% of femoropopliteal vessels are stented in the United States. This has been shown in multiple registries including the Excellence in Peripheral Artery Disease registry. Patency is improved with stenting, but target lesion revascularization has been inconsistent. There are many problems with stents in general: Treatment of in-stent restenosis can be challenging, stent fractures may occur and long-term outcomes beyond 3 years are unclear.

There will be a role for stenting in the future, but we do too much of it now. We have technology that could help you avoid stenting. I am a proponent of atherectomy preparation, an important step to initiate treatment to modify vessel compliance, allow a treatment to occur with high acute procedural success without the need to proceed with a stent.

Katzen: One of the more controversial areas of this discussion is use of venous stents for venous insufficiency. This area should be more challenged for appropriate data and documentation. Because so much of it is being done in an outpatient environment, there is little or no oversight or controlled studies being done.

Jaff: I worry that outpatient, high-cost procedures may not actually offer great value to patients. Some recent data suggest that rising Medicare costs covering endovascular interventions have come from office-based, outpatient lab procedures. The efficiencies offered by these office-based procedures need to be proven.

Dr. Bhatt: What is the importance of and how do we increase the multidisciplinary approach to vascular intervention?

Clair: There is increasing interaction between interventionalists and surgeons regarding options for treatment and discussions around what is the best treatment for patients. A good example of that is the BEST-CLI trial — the need to get an interventional viewpoint in addition to a surgical viewpoint to determine what is best for a patient. A healthy patient with extensive disease who has good vein available who can clearly undergo surgical revascularization will likely have better outcomes with surgical therapy, whereas an elderly frail patient with a very focal lesion would likely have better results with interventional therapy. It is this middle ground where the cross-specialty interaction is very helpful. As there is more exchange between groups, it creates a better understanding of what is best for different patients.

Wholey: What I have been looking for, for many years, is a multidisciplinary cooperative effort where physicians participate equally with strong subspecialty interests, from cardiologists to radiologists to vascular surgeons and so on.

Jaff: Collaboration has increased, either because people are expecting it, institutions are demanding it or patients want it — and that’s a good thing. If the interest is in what is best for the patient, there is no reason why we can’t talk about it. The interest shouldn’t be driven by specialty desires alone. However, many physicians haven’t been trained as team players; they have been trained to be individual experts. To bring teams together requires a lot of effort, time, and reassuring physicians that it isn’t meant to remove their autonomy, authority or financial outcomes. This is hard to do when you have many specialties doing the same thing and the literature doesn’t outline what is best.

The first thing anyone involved with performing vascular interventional procedures should do is spend time learning the basics: the epidemiology, natural history, treatment options, risks, benefits and so on. To learn the technical components of a procedure, most, if not all, interventional cardiologists will master them quickly, but to learn the indications and contraindications, the reasons for and against doing certain things is key, in my view.

White: One thing that we believe will be helpful at our center is the adoption of integrated practice units. If we work as a team — interventional radiologists, vascular surgeons, cardiologists, vascular medicine specialists and so on — we will give our patients the best outcomes possible.

Shammas: The cath lab of the near future has to be more versatile and flexible to allow for the growth of vascular procedures, by increasing collaboration.

Dr. Bhatt: What challenges persist?

Jaff: Payment challenges. Can we develop enough evidence to support that what we are doing actually matters from a clinical- and cost- and value-based perspective? Another challenge is determining the optimal algorithm for treatment for patients with various types of vascular disease.

Clair: As the U.S. payment system moves to accountable care organizations, a question is, what is the best way to treat someone with PAD for 5 to 10 years without bankrupting the system with multiple procedures, multiple interventions? We need a strong assessment of the most cost-effective therapy for these patients.

White: Peripheral vascular disease in general lacks the scientific rigor (randomized controlled trials) that cardiologists have brought to the coronaries. In the periphery, particularly the lower extremities, that scientific rigor does not exist. We are flooded with registry data, sponsored by industry, but lack head-to-head comparative trials. If someone were to ask me how we are going to treat the superficial femoral artery in the next 3 years, I would say that there are a lot of choices, from atherectomy to DCBs to stents, but I don’t have any real guidance or data by which to make those choices. Cardiologists can lift the field of vascular intervention, bringing their scientific discipline from the coronaries to the lower extremities.

Shammas: The biggest randomized controlled trial in the peripheral vascular disease field included a few hundred patients. I hope that interest in this field continues to grow and more people become involved so it will lead to more clinical trials to try to answer fundamental questions and to make sure that the algorithms are sound and scientifically strong. Vascular intervention procedures are becoming more complex and require a team approach to tackle them and retain high quality and reduce costs overall. We need to be cognizant of the costs of each procedure. Technologies are emerging. Procedures are becoming very expensive. We need to start thinking about cost-effectiveness analyses. The biggest challenge in the future is the cost and economics. We ask for tremendous data to be out there. We want that science, but we have to pay for that science.

Dr. Bhatt: What is your take-home message?

Jaff: Opportunities continue to abound for these very complicated patients with vascular diseases. On the downside, the window to prove that what we do matters is closing if we don’t demonstrate why these therapies are valuable.

Shammas: If you want to get into the field it is absolutely essential to learn the basics before you get your hands on the devices and start working with patients. Understand the background of the field, the theory behind it, the ins and outs of anatomy, the complications, etc. Special tracks at meetings like VIVA’s venous track and SCAI’s peripheral track and even things like simulators are helpful.

Katzen: We need to continue to explore new opportunities and treatments for vascular intervention, as with the heart and every aspect of the body. We work in an area of limitless possibilities, but will need to become used to focusing on those procedures, devices and other solutions that bring real value to patients and the system.

Wholey: The continuing overregulated control by the FDA and CMS with reimbursement cuts have seriously affected necessary research activity, which is most noticeable in carotid intervention. Major advances are occurring in CLI, acute ischemic stroke intervention, aortic endovascular repair and so on that will need an increasing number of adequately trained physicians to manage these procedures.

White: Atherosclerosis is a systemic disease, not confined to any single organ system or specialty. This demands that physicians work in multidisciplinary teams to provide optimal outcomes. We need to compensate physicians based upon “value-based outcomes,” not just the volume of procedures performed. The future of health care is to provide the right therapy, for the right patient, at the right time.

Clair: Vascular disease is increasing nationally and globally, and the problems we encounter will be identified in older, sicker individuals. We need to meet the challenge of tomorrow’s vascular disease by assessing outcomes, minimizing risk and working to assure we provide the right treatment, for the right patient at the right time. This is the only way we can continue to provide what our patients need without “breaking the bank.”

Disclosures: Bhatt reports advising for Cardax, Elsevier Practice Update Cardiology, Medscape Cardiology and Regado Biosciences; receiving research funding from Amarin, AstraZeneca, Bristol-Myers Squibb, Eisai, Ethicon, Forest Laboratories, Ischemix, Medtronic, Pfizer, Roche, Sanofi Aventis and The Medicines Company; serving as a site co-investigator for Biotronik and St. Jude Medical; and involvement with unfunded research for FlowCo, PLx Pharma and Takeda. Clair reports serving on the data and safety monitoring board for Bard, serving on advisory boards for Boston Scientific and Medtronic, and consulting for Endologix. Jaff reports advising for Abbott Vascular, American Orthotics and Prosthetics Association, Boston Scientific, Cardinal Health, Cordis and Medtronic Vascular; equity investment in PQ Bypass and Vascular Therapies; and serving as a board member for VIVA Physicians, a 501(c)3 not-for-profit education and research organization. Katzen reports advising for Bard, Boston Scientific, Ekos Corp and Medtronic. Shammas reports receiving research and educational grants from Boston Scientific, Cordis, Cardiovascular Systems, Inc., Medtronic and The Medicines Company and is a trainer for Boston Scientific and Covidien. White is co-chair of the BEST-CLI executive committee, a member of the interventional management committee for the CREST-2 trial, and member of the advisory boards for Lutonix, Neostem and Surmodics. Wholey reports no relevant financial disclosures.

The field of vascular intervention is evolving at a rapid pace. The use of catheter-based vascular interventions for the treatment of aortic, carotid, cerebrovascular, peripheral and other diseases continues to grow as a result of new technologies, an aging population and cross-specialty interest.

Now, more than ever before, interventional cardiologist involvement in the treatment of vascular diseases is increasing. Cardiology Today’s Intervention and Chief Medical Editor Deepak L. Bhatt, MD, MPH, gathered leading experts in the field to capture their thoughts on the present and future state of vascular intervention. The following discussion features perspective from Daniel Clair, MD; Michael R. Jaff, DO; Barry T. Katzen, MD; Nicolas W. Shammas, MD, MS; Christopher J. White, MD; and Mark Wholey, MD, on evolving technologies and techniques, multidisciplinary collaborations and challenges ahead.

Dr. Bhatt: Where do you see the field of vascular intervention going in the next 5 years?

White: In my mind, vascular intervention encompasses everything from the tip of the head to the tip of the toes. The field of percutaneous nonsurgical revascularization will continue to expand as new technologies replace invasive open surgeries. In every place we see open surgery being done today, tomorrow it will become less invasive, more endovascular.

Wholey: I anticipate dramatic growth in vascular interventions for the comprehensive CV system in all compartments except the coronary. An increasing number of interventional cardiologists are becoming involved in treatment of the entire CV system, not just the heart. Without question, treatment of peripheral artery disease has seen a significant increase by skilled interventionalists.

Deepak L. Bhatt
Shammas: Looking at the exponential growth in PAD treatment that has happened during the last 10 years, I suspect this is just the beginning. This is in contrast to the cardiac field, where there has been a decline in the number of procedures, almost 30% over the past few years.

I do both coronary and peripheral vascular work. My practice is divided almost 50/50 by peripheral vs. coronary disease. At one point, the peripheral vascular work was only about 20%. Over the past 5 years, it has increased to about 50%.

Cover illustration © Lisa Clark

Katzen: I view endovascular therapy in the broadest sense possible: anything that is treated through a blood vessel. One reason for the growth we are seeing is the aging population with atherosclerosis, aneurysm diseases and valvular diseases. Many resources and research initiatives are being made toward improved technologies in the less-invasive therapy movement for these patients.

Clair: What we are seeing now, and what we will continue to see more of, is increasing interaction between all of the specialties involved in the treatment of patients with vascular diseases.

Jaff: The onus is on us, as physicians, investigators, industry representatives and inventors, to prove that the therapies we currently apply to our patients actually matter — from a quality standpoint, from a cost standpoint, from an efficiency endpoint. There is a great deal of interest in the most effective technologies for vascular diseases, whether they are next-generation drug-device products, bioresorbable drug combination products, combinations of catheter-based intervention with an exercise program, or hybrid surgical and endovascular cases.

Dr. Bhatt: What areas in vascular intervention interest you most right now?

PAD and CLI

Katzen: Interventional treatment of PAD and critical limb ischemia (CLI) seems to be increasing at an epidemic proportion.

Shammas: PAD is highly prevalent but underserved worldwide. There continues to be a lot of interest in lower-extremity intervention, in particular. We now have many tools available to treat patients with lower-extremity PAD. Treatment of the femoropopliteal segment accounts for about 30% to 40% of all lower-extremity interventions performed.

PAGE BREAK

Wholey: More participants, especially cardiologists, are now involved with PAD and CLI interventions. The CLI results have been dramatic, especially in the infratibial vessels where both antegrade and retrograde access have opened up improved methods for recanalization.

I anticipate that the drug-coated balloons (DCBs) will have a major impact. The first DCB (Lutonix 035 Drug-Coated Balloon PTA Catheter, Bard/Lutonix) for patients with PAD was approved for use in the United States in October 2014 and the second (IN.PACT Admiral DCB, Medtronic) was approved in January 2015. Current research is now investigating a more efficient delivery system with controlled elution that will allow a higher tissue concentration over a longer period of time than the existing balloons.

Jaff: The combination of atherectomy and DCBs is an area of particular interest. Does it make a greater difference if you remove the plaque burden before delivering the drug via a balloon? Hopefully the answer will come in the near future.

For CLI, I think we will learn over the next 5 years the best initial strategy for patients. Results of the BEST-CLI trial and other ongoing industry-sponsored trials will hopefully provide the answers we need to treat these difficult patients.

White: I believe this area will become almost totally endovascular-based due to the new catheter-based technologies available and others on the horizon. Right now, about 20% of vascular procedures are surgical.

Christopher J. White

The techniques are drastically evolving. In the coronary, chronic total occlusions remain a persistent challenge. During the last 5 years, there has been an emergence of operators who are so technically skilled that they can cross virtually any coronary CTO. These techniques are now being used in the lower extremities. Below-the-knee vessels are the size of those in the coronary. What has limited us in the past when treating below-the-knee vessels has been long total occlusions. But the recent cross-fertilization of the CTO concepts from the heart have been brought down to the legs. Three years ago, we might have told a patient that he would lose his foot; today, we are applying CTO techniques and are saving limbs.

That is the beauty of the interventional cardiologist being in the heart and the peripheral arteries. You can say, “This worked for me in the right coronary artery, maybe it will work for me in the tibial artery.” More often than not, it does work.

Acute Stroke

Mark Wholey

Wholey: Of 800,000 acute strokes that occur annually in the United States and another 800,000 in Europe and Japan — roughly 2 million strokes per year — less than 5% are treated. With the introduction of the new retriever devices, stroke outcomes have been significantly improved with as high as 50% functional outcomes. With that, we are seeing dramatic changes, as noted in the current trials that included SWIFT PRIME, MR CLEAN and ESCAPE. Speed from the time of onset to the hospital is the critical element. There is a clear need for more interventionalists to be involved in acute stroke intervention.

White: At Ochsner Heart and Vascular Institute in New Orleans, cardiologists have been performing interventional acute stroke therapy for years, but we have done it with tools that were not well-suited to the task. Now, newer tools like stent retrievers (Solitaire, Covidien; Merci Retriever, Concentric Medical) are available for use. The small, flexible devices retrieve clots with stents that are attached at the end of a wire. It is a basket retriever, but looks like a stent. It is easier to manipulate than a coronary stent. In my opinion, cardiologists with carotid stent experience are extremely well-suited for acute stroke intervention.

There is a manpower shortage in the United States for the treatment of acute stroke. At our center, the reason interventional cardiologists started treating acute stroke was because we were invited by our neurologists. There was one neuroradiologist who couldn’t be on call 365 days a year. So the interventional cardiologists were asked to alternate coverage. Four U.S. states do not have any neuroradiologists. There are many places in the United States with more interventional cardiologists who can do this work. As cardiologists, we are members of a team led by a neurologist; I’m just the plumber. The decisions in acute stroke care are provided by the neurologist. But, if you ask me whether I can safely and effectively open the artery causing the stroke, the answer is yes.

PAGE BREAK

Pulmonary Embolism and Venous Disease

Jaff: Pulmonary embolism intervention is changing in a number of ways. There are new data on specific regimens of thrombolytic therapies and how it should be administered. There are also new devices that have proven in studies to be very effective, such as the EkoSonic Endovascular System (EKOS Corp.) for ultrasound-guided catheter-directed thrombolysis.

The development of a team-based approach to pulmonary emboli is also gaining traction. There is a lot of interest in taking very complicated patients, in whom we don’t have a lot of support from the literature on what is best to do, and bringing together experts around the virtual bedside of the patient to make a combined decision. We have been using the multidisciplinary Pulmonary Embolism Response Team (PERT) at Massachusetts General Hospital to improve the care of patients with pulmonary embolism. It has been a huge advance in the management of patients with pulmonary embolism, leading to incredibly accurate and fast ways to make a diagnosis. A consortium at Massachusetts General Hospital in 2015 brought together 40 other centers that are interested in learning how to put together a PERT program. Response teams could also be considered for the treatment and management of other vascular conditions as well.

Shammas: Looking at the recent interest of cardiologists with the venous system, there is no question that this will be a rapid area of growth, specifically acute treatment of proximal deep vein thrombosis and massive or submassive pulmonary embolism using pharmaco-mechanical means. Chronic treatment in the venous world will comprise symptomatic superficial venous disease, especially patients with advanced symptoms like venous ulcerations and major hyperpigmentation.

Carotid Artery Revascularization

White: Carotid artery revascularization has garnered a lot of interest recently. With improved embolic protection devices and an evidence-based reimbursement strategy, I think stenting will emerge as the dominant therapy in the next 5 years.

Katzen: I anticipate a significant change in the greater use of carotid artery stenting. I think the trial data will support that. We went through a low trough in the case of carotid stenting because of the regulatory situation and multiple disciplines that don’t agree with each other, which has created a unique political environment.

Wholey: If we ever get reimbursement with a broadened indication from CMS, we will likely see a reactivation of carotid stenting. This area was lively for many years, but in the absence of any reimbursement there has been very little research lately.

Renal Denervation

Barry T. Katzen
Katzen: On a longer time scale, I believe that catheter-based renal denervation will become an important therapy for a variety of conditions including treatment-resistant hypertension, arrhythmia disorders, HF and so on. Although longer-term data from the SYMPLICITY HTN-3 (Symplicity, Medtronic) trial showed no significant difference between renal denervation and a sham procedure in patients with resistant hypertension, other trials are underway such as the SPYRAL HTN program of renal denervation (Symplicity Spyral and G3, Medtronic) in patients with uncontrolled hypertension, the SYMPLICITY AF study of renal denervation (Symplicity Spyral and G3, Medtronic) and pulmonary vein isolation in patients with paroxysmal and persistent atrial fibrillation, and the REDUCE-HTN: REINFORCE study (Vessix, Boston Scientific) in patients with hypertension.

Abdominal Aortic Aneurysm

Daniel Clair
Clair: Technology for the treatment of abdominal aortic aneurysms (AAA) has been around and commercially available in the United States since 2000, when the first devices were approved. The follow-up remains fairly similar, which is intensive for patients who have endovascular treatment. That exposes all of the patients to a fair amount of risk. It is another area where there will be increasing scrutiny on what the most cost-effective treatment is. Recent research on endovascular AAA treatment showed reintervention rates at 2 years of about 10% to 12%, but that is likely a significant underestimate of the number of people who are having problems. The real problems begin from year 3 and beyond. In several study series, the risk for aneurysm rupture ranges from 1% to 5% within the first 2 to 5 years. That is a significant potential rupture rate compared with open surgical repair. Right now, we have a solution that is less morbid and less mortal early on — endovascular treatment — but we don’t know whether it is improving long-term survival and it may be increasing risk related to aneurysm rupture down the road. We need to see some improvements in the long-term outcomes of endografting for AAA repair. I think that ultimately will come from alternate strategies, not reiterations of current devices.
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Other Areas of Interest

Katzen: On the aortic side, there is also interest in the integration of valves and grafts. Certain areas that have been off-limit zones now represent exciting areas for the future including treatment of the ascending aorta, transverse aorta and branch endografts.

Clair: Right now, many operators performing interventions are exposed to radiation at fairly high doses over extended periods of time, exposing them to a significant amount of risk. There needs to be a way to provide guidance without exposing the individual to fluoroscopy radiation. That is a very important step.

Shammas: Embolic protection is being studied with transcatheter aortic valve replacement and also with PAD treatment. Data show that embolization occurs frequently during the treatment of PAD. There are certain subsets of patients who would benefit the most, such as those with the highest risk for embolization, CTOs, thrombotic occlusions and very long irregular calcified disease. However, use of embolic protection is inconsistent; many operators do not use it, while others use it in all cases. If we can pin down the highest-risk patients and apply these technologies, we will be practicing more cost-effective medicine.

Bioabsorbable stents have been tested in the coronaries and are awaiting approval. This technology could also be taken to the peripheral vascular bed. Having a drug-eluting bioabsorbable stent in the periphery that does its job and disappears after a while would be great.

Another area of interest is pharmacologic and lifestyle interventions. A conservative approach — quitting smoking, routine exercise, controlled risk factors — can be very powerful. I think we need more emphasis on pharmacotherapy and lifestyle interventions in certain patients.

Dr. Bhatt: What may we be doing in the near future that we are not doing today?

Michael R. Jaff

Jaff: I don’t think we will be intervening on asymptomatic patients. That came across loud and clear at the July 2015 CMS MEDCAC meeting. I anticipate more attention on trying to increase the medical management of the asymptomatic patient, making sure those patients get the same degree of risk factor interventions as do coronary patients.

Clair: Given long-term data on exercise therapy for claudication with infrainguinal disease, we should increase use of that therapy in patients. It is incredibly inexpensive; in every study that has analyzed it over extended periods of time, the outcomes of interventions are similar in terms of walking improvement and risks to the patient are minimal. In the CLEVER study, exercise therapy had similar outcomes to interventional therapy in patients with aortoiliac occlusive disease. In my mind, until something changes with the outcomes of interventional therapies that radically shifts the needle, we will see many more claudicant patients treated with exercise therapy rather than interventional therapies.

Dr. Bhatt: What procedures are we doing today that might not always be at the forefront of care?

White: Antegrade punctures may go away in the near future. This is done because the catheter lengths aren’t adequate. We need longer catheters to get to the foot, for example. Instead of using contralateral femoral artery access, we take the shortcut with an ipsilateral antegrade approach, which has a higher risk for complications and bleeding. I think the future will be radial access with much longer catheters. We will be using radial access to treat lesions below the knee. Femoral antegrade punctures will be replaced by longer catheters from safer access points.

Clair: We will be looking at ways to reduce the cost of vessel preparation and medicated therapies for any vessel treatment that we do.

Nicolas W. Shammas

Shammas: If you look at the data, we have a very aggressive approach to stenting. About 60% of femoropopliteal vessels are stented in the United States. This has been shown in multiple registries including the Excellence in Peripheral Artery Disease registry. Patency is improved with stenting, but target lesion revascularization has been inconsistent. There are many problems with stents in general: Treatment of in-stent restenosis can be challenging, stent fractures may occur and long-term outcomes beyond 3 years are unclear.

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There will be a role for stenting in the future, but we do too much of it now. We have technology that could help you avoid stenting. I am a proponent of atherectomy preparation, an important step to initiate treatment to modify vessel compliance, allow a treatment to occur with high acute procedural success without the need to proceed with a stent.

Katzen: One of the more controversial areas of this discussion is use of venous stents for venous insufficiency. This area should be more challenged for appropriate data and documentation. Because so much of it is being done in an outpatient environment, there is little or no oversight or controlled studies being done.

Jaff: I worry that outpatient, high-cost procedures may not actually offer great value to patients. Some recent data suggest that rising Medicare costs covering endovascular interventions have come from office-based, outpatient lab procedures. The efficiencies offered by these office-based procedures need to be proven.

Dr. Bhatt: What is the importance of and how do we increase the multidisciplinary approach to vascular intervention?

Clair: There is increasing interaction between interventionalists and surgeons regarding options for treatment and discussions around what is the best treatment for patients. A good example of that is the BEST-CLI trial — the need to get an interventional viewpoint in addition to a surgical viewpoint to determine what is best for a patient. A healthy patient with extensive disease who has good vein available who can clearly undergo surgical revascularization will likely have better outcomes with surgical therapy, whereas an elderly frail patient with a very focal lesion would likely have better results with interventional therapy. It is this middle ground where the cross-specialty interaction is very helpful. As there is more exchange between groups, it creates a better understanding of what is best for different patients.

Wholey: What I have been looking for, for many years, is a multidisciplinary cooperative effort where physicians participate equally with strong subspecialty interests, from cardiologists to radiologists to vascular surgeons and so on.

Jaff: Collaboration has increased, either because people are expecting it, institutions are demanding it or patients want it — and that’s a good thing. If the interest is in what is best for the patient, there is no reason why we can’t talk about it. The interest shouldn’t be driven by specialty desires alone. However, many physicians haven’t been trained as team players; they have been trained to be individual experts. To bring teams together requires a lot of effort, time, and reassuring physicians that it isn’t meant to remove their autonomy, authority or financial outcomes. This is hard to do when you have many specialties doing the same thing and the literature doesn’t outline what is best.

The first thing anyone involved with performing vascular interventional procedures should do is spend time learning the basics: the epidemiology, natural history, treatment options, risks, benefits and so on. To learn the technical components of a procedure, most, if not all, interventional cardiologists will master them quickly, but to learn the indications and contraindications, the reasons for and against doing certain things is key, in my view.

White: One thing that we believe will be helpful at our center is the adoption of integrated practice units. If we work as a team — interventional radiologists, vascular surgeons, cardiologists, vascular medicine specialists and so on — we will give our patients the best outcomes possible.

Shammas: The cath lab of the near future has to be more versatile and flexible to allow for the growth of vascular procedures, by increasing collaboration.

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Dr. Bhatt: What challenges persist?

Jaff: Payment challenges. Can we develop enough evidence to support that what we are doing actually matters from a clinical- and cost- and value-based perspective? Another challenge is determining the optimal algorithm for treatment for patients with various types of vascular disease.

Clair: As the U.S. payment system moves to accountable care organizations, a question is, what is the best way to treat someone with PAD for 5 to 10 years without bankrupting the system with multiple procedures, multiple interventions? We need a strong assessment of the most cost-effective therapy for these patients.

White: Peripheral vascular disease in general lacks the scientific rigor (randomized controlled trials) that cardiologists have brought to the coronaries. In the periphery, particularly the lower extremities, that scientific rigor does not exist. We are flooded with registry data, sponsored by industry, but lack head-to-head comparative trials. If someone were to ask me how we are going to treat the superficial femoral artery in the next 3 years, I would say that there are a lot of choices, from atherectomy to DCBs to stents, but I don’t have any real guidance or data by which to make those choices. Cardiologists can lift the field of vascular intervention, bringing their scientific discipline from the coronaries to the lower extremities.

Shammas: The biggest randomized controlled trial in the peripheral vascular disease field included a few hundred patients. I hope that interest in this field continues to grow and more people become involved so it will lead to more clinical trials to try to answer fundamental questions and to make sure that the algorithms are sound and scientifically strong. Vascular intervention procedures are becoming more complex and require a team approach to tackle them and retain high quality and reduce costs overall. We need to be cognizant of the costs of each procedure. Technologies are emerging. Procedures are becoming very expensive. We need to start thinking about cost-effectiveness analyses. The biggest challenge in the future is the cost and economics. We ask for tremendous data to be out there. We want that science, but we have to pay for that science.

Dr. Bhatt: What is your take-home message?

Jaff: Opportunities continue to abound for these very complicated patients with vascular diseases. On the downside, the window to prove that what we do matters is closing if we don’t demonstrate why these therapies are valuable.

Shammas: If you want to get into the field it is absolutely essential to learn the basics before you get your hands on the devices and start working with patients. Understand the background of the field, the theory behind it, the ins and outs of anatomy, the complications, etc. Special tracks at meetings like VIVA’s venous track and SCAI’s peripheral track and even things like simulators are helpful.

Katzen: We need to continue to explore new opportunities and treatments for vascular intervention, as with the heart and every aspect of the body. We work in an area of limitless possibilities, but will need to become used to focusing on those procedures, devices and other solutions that bring real value to patients and the system.

Wholey: The continuing overregulated control by the FDA and CMS with reimbursement cuts have seriously affected necessary research activity, which is most noticeable in carotid intervention. Major advances are occurring in CLI, acute ischemic stroke intervention, aortic endovascular repair and so on that will need an increasing number of adequately trained physicians to manage these procedures.

White: Atherosclerosis is a systemic disease, not confined to any single organ system or specialty. This demands that physicians work in multidisciplinary teams to provide optimal outcomes. We need to compensate physicians based upon “value-based outcomes,” not just the volume of procedures performed. The future of health care is to provide the right therapy, for the right patient, at the right time.

Clair: Vascular disease is increasing nationally and globally, and the problems we encounter will be identified in older, sicker individuals. We need to meet the challenge of tomorrow’s vascular disease by assessing outcomes, minimizing risk and working to assure we provide the right treatment, for the right patient at the right time. This is the only way we can continue to provide what our patients need without “breaking the bank.”

Disclosures: Bhatt reports advising for Cardax, Elsevier Practice Update Cardiology, Medscape Cardiology and Regado Biosciences; receiving research funding from Amarin, AstraZeneca, Bristol-Myers Squibb, Eisai, Ethicon, Forest Laboratories, Ischemix, Medtronic, Pfizer, Roche, Sanofi Aventis and The Medicines Company; serving as a site co-investigator for Biotronik and St. Jude Medical; and involvement with unfunded research for FlowCo, PLx Pharma and Takeda. Clair reports serving on the data and safety monitoring board for Bard, serving on advisory boards for Boston Scientific and Medtronic, and consulting for Endologix. Jaff reports advising for Abbott Vascular, American Orthotics and Prosthetics Association, Boston Scientific, Cardinal Health, Cordis and Medtronic Vascular; equity investment in PQ Bypass and Vascular Therapies; and serving as a board member for VIVA Physicians, a 501(c)3 not-for-profit education and research organization. Katzen reports advising for Bard, Boston Scientific, Ekos Corp and Medtronic. Shammas reports receiving research and educational grants from Boston Scientific, Cordis, Cardiovascular Systems, Inc., Medtronic and The Medicines Company and is a trainer for Boston Scientific and Covidien. White is co-chair of the BEST-CLI executive committee, a member of the interventional management committee for the CREST-2 trial, and member of the advisory boards for Lutonix, Neostem and Surmodics. Wholey reports no relevant financial disclosures.