The CX Imaging Day provided a comprehensive programme of state-of-the-art imaging that is applied to the aorta, carotid, peripheral arteries and veins, including planning and using hybrid theatres, robotics, 3D fusion and guidance, intravascular ultrasound, perfusion angiography, cone beam computed tomography and carbon dioxide angiography.

This year’s Imaging Day was divided into two parts, giving attendees the opportunity for maximum learning and understanding. The morning session saw the presentation of the latest data in the Olympia Room Learning Centre, while in the afternoon, various imaging providers, including Philips, GE Healthcare, Siemens, Hansen Medical, Volcano and Ziehm Imaging, hosted “Ask the Expert” workshops at their stands in the Exhibition Hall. These workshops allow attendees to interact in small groups with the experts and to look at the imaging systems and tools, providing them with a unique view of the technology.

GE Healthcare

GE Healthcare took the opportunity to show the flow of its solutions from sizing to the 3D fusion from table side. There was also focus on dose optimisation management.

Alejandra Gonzalez, European marketing product manager for Interventional Systems at GE explained, “We provided an educational framework where we raised awareness of the key elements that physicians need to take care of in order to reduce the dose or optimise the dose strategy. We wanted to do it in an educational way and at the same time a more interactive way as well.”

Guiding the presentations and providing personal input were physician experts Stephan Haulon (Lille, France) and Adrien Hertault (Lille, France). Haulon explained what took place saying, “we showed the attendees a couple of cases that were sized on a workstation so they had the ability to actually manipulate the workstation and then we had them do a fusion registration to show them how straightforward a technology it is and how user friendly it is. We also had a big focus on dose exposure which is a real concern for vascular surgeons today because we are doing more and more radiation exposure procedures. We had a quiz which stirred a lot of questions and debates. So this was actually quite passionate and really interesting.”

Commenting on the workshop Haulon added, “There was a lot of interaction and those people would never stand up in a large room to ask a question, whereas here they were very enthusiastic about sharing their comments and asking us for more details so I think it was a very valuable workshop.”

Hansen Medical

Hansen Medical presented the Magellan robotic system which helps physicians navigate through the vasculature. Joe Guido, vice president marketing and business development explained that the system is designed to “make the procedure more efficient and more predictable for physicians and also allows physicians to stay out of the field of radiation. The robotic system will drive robotic catheters that you can shape and control without having to do exchanges for other catheters.”

Physician experts Barry Katzen (Miami, USA) and Celia Riga (London, UK) presented their experiences with intravascular robotics and the Magellan robotic system.

Guido commented on the workshop saying that many physicians are very curious about the technology and the practical applications and how it can benefit them and their practice. “An expert is much more accessible at the stand and it is a much more intimate environment. It encourages physicians to listen to the presentation and then speak to the experts and ask one-on-one questions,” he said.

Philips

Philips presented its technology and had physician experts Frank Vermassen (Ghent, Belgium) and Jim Reekers (Amsterdam, Netherlands) on hand to answer queries from physician-attendees. Philips demonstrators showcased the company’s technology including the VesselNavigator, a live image guidance solution; 2D Perfusion; Veradius Unity, a C-arm with flat detector; and gave advice on considerations when purchasing a hybrid room.

Commenting on the Veradius Unity, Philips demonstrator Marianne Kwakernaat said that the technology was developed, “to help get a more united team in the OR because there was a lot of frustration between doctors and operators who did not understand each other, so we made a lot of improvements to our systems to first, make it more easy to communicate, so we added some tools, and second, we made a new touchscreen which is very interactive and easy to use.”

She added that the workshop was a good vehicle to give the physicians the opportunity to see the products and figure out which one is most suitable to their hospital and their uses.

Siemens

Siemens showcased the complete workflow for EVAR procedures, starting with the preoperational CT scan. The company also gave attendees the opportunity to see the PURE software technology for the Artis zeego.

Dirk Sunderbrink, business manager, Therapy Systems at Siemens described the system saying, “It allows the vascular surgeon 2D and 3D registration with much less dose and in much less time than with previous systems. This PURE software guides the vascular surgeon through the procedure automatically to have fusion imaging available to guide them through the procedures.” He added, “The teaching opportunity is important to us because there are presentations, but it is much easier to really see it hands-on.”

Dittmar Böckler (Heidelberg, Germany) was on hand providing an expert position, giving attendees the opportunity to ask questions about the Siemens technology.

Volcano

Volcano showcased its intravascular ultrasound (IVUS) system, which provides detailed and accurate measurements of lumen and vessel size, plaque area and volume, and the location of key anatomical landmarks.

Physician expert Fabrizio Fanelli (Rome, Italy) was present to give his personal perspective of the technology and to answer attendees’ queries. At the stand, demonstrations were done showing real time sizing and procedure assessment with reduced exposure and contrast.

Volcano demonstrator Fiorella De Nicolais explained that the IVUS technology helps differentiate the four plaque types: fibrous, fibro-fatty, necrotic core and dense calcium.

She added that, “Not everyone knows IVUS, or the way it works or the benefits of using it, so the workshop is about getting more details and learning how the technology works.”

Ziehm Imaging

Ziehm Imaging featured its mobile hybrid room concept which consists of a mobile C-arm that has all the imaging capabilities of a fixed, installed hybrid room—high power imaging, a liquid cooling system, flat panel technology, fully motorised movements.

Visitors to the stand heard presentations from experts Wolfgang Keller (Nuremberg, Germany) and Peter Goverde (Antwerp, Belgium), who spoke about Ziehm’s mobile interventional suite and their clinical experiences with a mobile hybrid OR.

Summarising, Axel Kouril from Ziehm Imaging said, “As opposed to fixed installed hybrid ORs which are very expensive and have additional installations costs of enforcing the floor or the ceiling, and lead protection, this system has the size of a normal mobile C-arm and the imaging capabilities of a fixed installed system (up to 90%), but it is cheaper, it is mobile, and more flexible.”

The second day of the CX Venous Workshop was held yesterday on the Upper Level of the Gallery, rounding off a busy week in which more than 950 people visited over the two days—a new record for the Workshop. Once again the educational stations, of which there were more than 30, were packed with delegates looking forward to one-on-one time with the distinguished Charing Cross Symposium faculty.

As was the case on Wednesday, the “Endovenous Ablation Village” was running, showcasing all available techniques to ablate truncal veins, along with practical training sessions teaching ultrasound-guided cannulation, catheter positioning and tumescent anaesthesia.

While the first day of the workshop focused largely on varicose veins and superficial venous issues, yesterday went deeper into the vein by examining acute deep vein thrombosis, intravascular ultrasound and deep venous stenting. Every station saw a significant amount of traffic, with delegates showing a keen interest in the intravascular ultrasound and deep vein thrombosis stations.

Ian Franklin, one of the course directors, said “Today we have had a big change of interest to deep venous—treatments of deep vein thrombosis, deep vein stenting, intravascular ultrasound, pelvic vein embolisation and so on—and it is packed. There is not a single empty training station, everyone has good interest and it is sustained. We deliberately have this flexible format so people can come and go—if they find they have a gap in the programme they can come and join us and make sure their time is used profitably.”

As the workshop drew to a close for another year, thoughts turned towards 2016. “Every year we change the event and it has never been the same as it was before, so next year will definitely be different,” said Franklin. “One thing I would consider is bringing in recorded live cases of all the new techniques we are showcasing to complement the hands-on demonstrations, using screens and some commentaries.”

With the workshop in its seventh year, there is always the opportunity to resurrect popular aspects of previous years’ Workshops. For example, Franklin suggested, “I would also like to bring back interactive discussion of complicated and difficult cases. That was always very popular, especially when you had a series of well-known experts all discussing how best to handle a case. Quite often we are showcasing different techniques and then once you have learnt that technique there comes the discussion of when to use it, so I think those case-based discussions complement the learning too.”

Day 2 offered stations covering: thermal (laser), thermal (radiofrequency ablation), non-thermal, practical training stations, valves, vascular ultrasound training simulator, venous malformations, pelvic venous imaging, pelvic vein embolisation, acute deep vein thrombosis, caval filters, follow-up protocols, air plethysmography, intravenous ultrasound and deep vein stenting.

Alma Lasers was exhibiting its VascuLife minimally invasive varicose vein laser treatment with robotic pullback. Having received CE mark and FDA approval recently, the VascuLife station had plenty of visitors looking to learn about the robotic pullback capability, which standardises pullback rate safely and allows a surgeon to focus on other tasks while pullback is completed. Shira Doron, marketing director at Alma Lasers, believes that the CX Venous Workshop gave companies and physicians a chance to interact and share information in an informal and purely scientific setting. She said, “Physicians view this as their professional platform as opposed to booths, which may feel like more of a marketing platform. They come here and it is all about the device and what it can do. You do not need to see movies or brochures—it is all about the technology.”

The new ArtVentive EOS device also was highlighted yesterday. Krzysztof Pyra (Lublin, Poland) spoke his experience with the EOS device treating ovarian veins for pelvic congestion syndrome. In addition, treatment of spermatic vein varicoceles were also presented. Pyra discussed his approach to diagnosing and treating pelvic vein incompetence. According to Pyra, of particular note was the immediacy of occlusion with the EOS device and shorter procedure times. Pyra uses a combination of EOS and sclerosant to occlude the pelvic veins.

Michael Dake, Stanford, USA, presented the initial results with the GORE TAG Thoracic Branch Endoprosthesis (TBE), a new device for treatment of the aortic arch at CX yesterday.

Dake, Stanford, USA, presented the initial results with the GORE TAG Thoracic Branch Endoprosthesis (TBE), a new device for treatment of the aortic arch.

Dake told delegates that the GORE TAG TBE is a single branch device that consists of an aortic component, a side branch component and an optional aortic extender. The side branch component is delivered through a sheath and docks into the aortic component portal which allows for perfusion of a single arch branch vessel. The device is currently being studied in a zone 2 (left subclavian) feasibility study and a zone 0/1 (brachiocephalic and left common carotid) early feasibility study in the USA.

Currently, there are 20 patients (10 men and 10 women, mean age 75.4 years) successfully enrolled in zone 2 and one patient enrolled in zone 0/1. All 20 patients in zone 2 had successful access and deployment of the TBE device with the side branch component patent at the end of the procedure. Additionally, all side branch components remain patent.  At one month, there have been no reported patient deaths or stroke. The left ankle brachial index (1.1) remains the same from pre-procedure to one month. There were no endoleaks that required reintervention.

The first two zone 0 patients were treated with the TBE device at the University of Pittsburgh Medical Center by Michel Makaroun, and at the Mayo Clinic by Gustavo Oderich. The protocol requires the patient to be treated in two phases with phase 1 revascularisation and phase 2 endovascular procedure. In phase 1, the patient underwent cervical debranching of the arch via a carotid to carotid bypass followed by a left carotid to left subclavian transposition. The proximal left common carotid and left subclavian artery was suture ligated.

Dake spoke about the patient treated about Makaroun and said the patient tolerated the procedure well without any neurological complications. The patient was assessed and deemed stable to proceed to phase 2 after 24 hours. In phase 2, the aortic component was advanced and deployed at the target location near the brachiocephalic artery. The sheath was advanced without difficulty into the portal of the aortic component into the brachiocephalic artery. The side branch component was advanced and deployed. Final arteriography showed excellent flow into the arch vessels, aneurysm exclusion, and complete apposition of the aortic component both proximally and distally.

Dake concluded: “These early results are promising with 100% technical success and side branch patency along with 0% death or stroke at one month.”

Although there is strong evidence that multidisciplinary foot care services can reduce the number of amputations associated with diabetic foot, access to such services remains patchy. Cliff Shearman (Southampton, UK) believes that healthcare providers are not doing enough to improve access. He says that it may take litigation from patients, who have lost a foot through poor care, to persuade healthcare providers to increase access, which he says would be “a great pity” because it should be “evidence and enthusiasm” that drives change.

Speaking at the CX ilegx Collaboration Day yesterday, Shearman explained that early diagnosis and prompt treatment can help to reduce the risk of amputation in patients with diabetic foot. He added that there is “strong evidence” to show that well-organised diabetic foot teams, working across primary and secondary care, can ensure that patients receive the care they need. Shearman noted that research indicates that such teams can the reduce rate of amputation by up to 80%. Furthermore, he reported that having a foot care team at his hospital (Southampton) has resulted in costs savings of £1,695,600 and a reduction in total beds of 5,662.

However, in the UK, only around 50% of people with diabetes receive the recommended nine health checks, including foot examination, and up to one in five hospitals do not have a diabetic foot protection team. Shearman commented: “I think healthcare professionals are now much more interested in the need to provide good care to reduce the amputation rates, but there is a lack of drive from government and healthcare providers to push this forward. At the moment, in the UK, we do not have core criteria for commissioning diabetic foot care services—all we can really do is to try to emulate those who have created good services,” he said.

According to Shearman, there are three steps to encouraging healthcare providers to take steps to increase access to foot care services: enthusiasm and evidence, naming and shaming, and litigation. He claimed that we are now the stage of “naming and shaming”—ie, showing how amputations rates can be “staggeringly reduced” with timely access and multidisciplinary team working. “If that does not work, it will be litigation that drives change. The number of ligation cases is rising enormously because people are recognising that they have not received good care and therefore, are taking action against their healthcare provider. It will be a great pity if litigation is what prompts change as it should be enthusiasm and evidence.” 

Michael Edmonds (London, UK), who (like Shearman) is a course director of the CX ilegx Collaboration Day, agrees that poorly organised services—rather than a lack of effective treatment—are a cause of patients with diabetic foot having to undergo amputation. He said one of the key goals of ilegx, which was started in 2008, was to “encourage interdisciplinary collaboration that spans the primary and secondary services, and develop and implement best practice approach to save legs.”

Shearman told CX Daily News: “I hope delegates who attend the course will go away fired up with the knowledge that they can make a difference [by being enthusiastic about improving care and encouraging multidisciplinary working] and that they can help their centres save money as well as improve outcomes. Improving the care of patients with diabetic foot is not about hiring lots of new people or lots of new technology. It is about working as a team.”

Treatment options for diabetic foot

During the CX ilegx Collaboration Day, there were several talks about treatment options for patients with diabetic foot. Toby Richards (London, UK) spoke about a novel wound therapy called CelluTome (KCI). He said that this involved taking an epidermal graft off a patient’s leg, without any form of anaesthetic, by applying local heat to create microblisters that were then transferred onto a wound.

To assess the system, Richards and colleagues evaluated its use in a case series of 30 patients who were candidates for split skin grafts—most of whom had chronic wounds, with Richards noting: “so, we are not picking winners” (ie. patients with wounds that had a better chance of complete healing).

He stated that the “most important thing” was that the average time for donor site healing was 5.43±1.54 days, the mean pain score was 1.33±0.95, and the Vancouver Scar Scale was 0 for all cases at six weeks after therapy.

Richards reported that 17 patients had complete healing (12 in under six week and four in under eight weeks) and that seven grafts failed due to infection, adding “one of the problems we had is that the graft looks like a biofilm at two weeks and a nurse who was not familiar would come along and think it needed cleaning, so there goes your graft. While you get used to this look, you need to leave the dressing on as long as possible, and then you will start to get good results.” He concluded that it was a novel technology that was “feasible” and it that “certainly does work”, saying: “as with all new technologies, it should be tested in a proper trial before we introduce it into normal practice. Therefore, we will be evaluating it in a randomised controlled trial.”

Jennifer Tremlett (London, UK) also spoke about wound care techniques, including platelet rich plasma, larvae therapy, and negative wound pressure. Like Shearman and Edmonds, Tremlett advocated “multidisciplinary working” because it “provides better outcomes”. Furthermore, Dean Huang (London, UK), who spoke about advances in distal endovascular surgery, said that the need for collaborative working and rapid access to diagnosis and intervention were “probably two of the most important points” in his talk.

Micro-mesh stents and sustained anti-embolic action to reduce cerebral embolisation may contribute to solving the remaining limitations of carotid stenting, according to Alberto Cremonesi (Cotignola, Italy), who spoke at CX 2015 (28 April–1 May, London, UK).

Cremonesi examined the potential for micro-mesh stents to improve existing carotid artery stenting outcomes.

He told delegates that the correct technique for performing a carotid artery stenting was to conduct a pre-procedural evaluation for common carotid engagement, to select the correct stent and to select and manage an embolic protection device.

Cremonesi said that it is already known that “not all plaques are the same”, and that “carotid artery stenting and carotid endarterectomy are —and will remain—emboli-generating procedures”. He told the audience that it is possible to give sustained anti-embolic over time using specific stents.

When a poorly-selected stent is used for carotid artery stenting, intra-strut prolapse can occur resulting in post-procedural embolic events. The difficulty then, commented Cremonesi, is that “lesions in the carotid arteries are often anatomically and morphologically very challenging. For this reason, plaque coverage can play an important role.”

The use of stenting strategies such as open cell, closed cell and hybrid geometry can be considered “time honoured”. Now, vascular specialists have access micro-mesh double layer carotid stents (Terumo, InspireMD and Gore), said Cremonesi, whose personal experience is with the Roadsaver carotid stent from Terumo.

Cremonesi admitted that “In terms of data, we do not have very much at the moment” for the use of micro-mesh. Some data do exist from the CARENET all-comer trial, in which 30 patients saw “very good” outcomes without any neurological events up to five months follow-up. A further multicentre trial with 100 patients, CLEAR-ROAD, is also beginning, though Cremonesi said that he did “not want to conclude anything” about it yet.

“We are probably changing the paradigms in carotid artery stenting, because with these micro-mesh stents and their sustained anti-embolic action, we can solve the remaining limitation of carotid stenting,” ended Cremonesi.

Discussing his presentation with the audience, Cremonesi mentioned that “two-thirds of the embolic complications are in the post-procedural phase.” When session chairman Roger Greenhalgh asked about the cause for this later onset of complications, Cremonesi told him that it was due to the stent interacting with and cutting the plaque in the carotid artery, which can occur during the phase and even up to 48 hours later. Cremonesi made it clear that this problem is one of the carotid artery, rather than one associated with the aortic arch.

There have been vast technological advances that have enabled the final frontier of the aorta, the diseased ascending aorta and arch, to be treated by completely endovascular means. Simultaneously, there have also been advances in open repair. Also, with perioperative stroke remaining a principal risk with TEVAR, the high incidence of cerebral embolisation with the procedure is a problem that needs wider recognition, delegates heard yesterday.

In a panel discussion during the session on interventions for ascending aorta and aortic arch, Roger Greenhalgh, chairman of the CX Organising Board, pressed the panel to comment on patient mortality after open repair and endovascular repair.

The mortality rate for open repair is around 3%, even when there is involvement of the aortic valve, said Stephen Large, Cambridge, UK. With endovascular repair, it approaches 10%, said Dittmar Böckler, Heidelberg, Germany. Subsequently, 65% of the CX 2015 audience voted against the motion that the heyday of open aortic surgery is over.

Richard Gibbs, London, UK, told CX delegates yesterday that there was a high rate of embolisation during arch and descending thoracic intervention that could be observed as silent cerebral infarction on new imaging techniques. The results from the study he presented showed that there is a 70% silent cerebral infarction on MRI and that there is postoperative neurocognitive decline in patients with silent cerebral infarctions.

Gibbs made the point that stroke, which was caused by cerebral embolisation, was a relatively crude surrogate, but a clinically relevant measure of microembolisation. The stroke rate for TEVAR ranges between 3% and 6%, said Gibbs, with embolisation being caused by the passage of stiff wires, soft wires, devices and manipulation within the diseased aorta. The risk factors are the atheromatous burden within the aorta and using a proximal landing zone. Hypotension is also very important, he said.

“A much subtler way of looking at microembolisation is with diffusion-weighted MR that detects acute ischaemia that is due to cerebral oedema. These lesions appear within 24 hours of the insult and last up to 14 days, and show as hyperintense bright areas that are easy to recognise,” Gibbs noted.

Gibbs then showed diffusion-weighted cerebral MR images from a patient who had silent cerebral infarctions but did not develop signs or symptoms of clinical stroke following TEVAR. “Therefore what we see here is silent stroke, or silent cerebral infarction, which is imaging evidence of cerebral infarction, without a history of acute neurological dysfunction attributable to the lesion,” Gibbs said.

He qualified that he believed the term silent cerebral infarction is a misnomer because there is an increasing body of evidence that suggests that silent cerebral infarction is associated with depression, dementia, Alzheimer’s, future increased risk of stroke and mortality.

Published literature shows a significant rate of cerebral infarction with various different interventions involving the arch and unsurprisingly transcatheter aortic valve implantation (TAVI), which is the biggest device and causes the most cerebral infarction, he explained.

“When it comes to TEVAR, there is very little literature, and one paper suggests that there is a 63% risk of cerebral infarction with the procedure,” said Gibbs referring to the data from 19 patients from Kahlert et al published in the Annals of Thoracic Surgery in 2014 that found diffusion-weighted MR evidence of cerebral infarction after TEVAR in 12 of 19 (63%) undergoing the procedure for a variety of indications. There was no overt clinical stroke seen in these patients.

Gibbs then presented the pilot work done by his team on the rates of silent cerebral infarctions during TEVAR, the presence of silent cerebral infarction on MR and whether there are neurocognitive changes afterwords.

“We included 44 patients undergoing TEVAR and looked at the burden of atheroma within the arch of the descending aorta based on the American Heart Association grading method. The patients had bidirectional transcranial Doppler, which is a direct measure of cerebal microembolisation. “A subset of these patients had pre-and postoperative MR looking for more evidence of infarction (23 patients). Another subset had neurocognitive assessment before the intervention, after the intervention in hospital and eight weeks later to see if any changes persist,” said Gibbs.

Forty one TEVAR procedures involving the arch and descending aorta were performed for a variety of pathologies. Of these 21 were standard and 20 were complex involving the use of branches, scallops or adjunctive surgical procedures. “We had fairly proximal landing zones,” he noted.

“Looking at the specific procedural steps, we see clearly that stent graft deployment carries the most significant rate of embolisation,” said Gibbs. He then showed a transcranial Doppler during stent graft deployment where a burst of cerebral embolisation was visible in both hemispheres. “The highest activity of cerebral embolisation was when the device was deployed. Increased embolisation was associated with the left hemisphere more than the right; stent manipulation more than wire and catheter passage; a higher grade of atheroma compared to a lower grade (so a higher burden of disease); chronic rather than acute disease. Patients who had a stroke had the highest rate of embolisation. A proximal landing zone rather than distal one had a higher rate of cerebral embolisation. In the group where we looked for evidence of silent cerebral infarction, 70% (16/23) of our patients had this, mostly in the left hemisphere and mostly in the territory served by the middle cerebral artery. Ten per cent of these patients had a clinical stroke,” said Gibbs.

When the researchers selected out the data for older patients from the group, they found that executive function diminished and stayed down at eight weeks, memory diminished and manual dexterity got worse.

“There is a significantly high rate of cerebral embolisation during TEVAR and the more proximal you go, the worse it is. There is a definitive and radiologically proven damage to the brain and these patients do pay a price for this. We have to be thinking about how we can intervene [either pharmacologically or by using devices],” concluded Gibbs.

Scarcity of literature on proximal landing zone and TEVAR outcomes

Dittmar Böckler stated that while the relationship between the proximal landing zone and outcome was well-documented in the EVAR literature, there were very few publications focused on how the proximal landing zone influences patient outcomes with TEVAR in the arch, and noted the low level of evidence.

“There are no randomised controlled trial data on open versus endovascular approaches and there are no meta-analyses. The data come from limited European registry data from the Relay registry, Traviata registry and European CTAG registry,” he noted.

Böckler drew attention to the fact that there was no consensus in the literature and guidelines on the appropriate proximal neck length and that this variation was reflected in the instructions for use from manufacturers, as the target landing zone is depending on stent graft diameter.

“The appropriate proximal landing zone for TEVAR is not defined. Arch type and atheroma seem to influence stroke risk during TEVAR in the arch. “There is strong need for new refined conformable devices in the arch including branched stent graft technology,” Böckler said.

Value of medication

Frank Lederle, Minneapolis, USA, speaking on the value of medication such as statins before aortic arch catheterisation, stated that there was very little trustworthy randomised controlled trial data to go by. He reviewed evidence that bears on whether perioperative statins or aspirin benefit patients having a thoracic aortic procedure. “Analyses showing benefit of perioperative use rely on weak and doubtful studies. When it comes to aspirin, there are no data on perioperative benefit, but there is an increased major and minor bleeding,” he said.

Lederle drew attention to the fact that many patients with aortic aneurysm have arteriosclerotic cardiovascular disease and should be on statins and aspirin long-term. “There is no good evidence that statins or aspirin improve long-term outcomes for patients with aortic arch patients without arteriosclerotic cardiovascular disease, so some of these patients will not be on these medications. Questions remain on when whether or not patients are on them long-term and whether they should be used perioperatively,” he said.

Open surgery

Stephen Large, Cambridge, UK, a cardiac surgeon, outlined the case for open surgery in interventions for ascending and arch of the aorta, the current gold standard approach.

Large noted that not operating resulted in a “dreadful attrition”. “We know that there is an increase in attrition correlated with the increase in aneurysm size, the hingepoint being around 5.5cm in the ascending and arch, which is associated with an acceleration in terms of stroke, dissection rupture and death,” he said.

“What we very often do in the ascending aorta is deal with an associated post-aortic valvular lesion either by an interposition graft, that is something placed above the coronary artery ostia, really at the level of the sinotubular junction, and right up to the origin of the innominate artery—a true ascending aortic replacement. We can, if we are in trouble (of course with involvement of pathology within the aortic root), replace the aortic root and that always requires reimplantation of the coronary ostia, which brings a raft of problems of threatening ischaemia with it. Up until relatively recently, this involved automatic replacement of the aortic valve. There is now a keen interest in considering valve preservation procedures, something that I have fought against for many years, because the aortic valve is embryologically of the same origin as the ascending aorta. However, counterintuitively, it appears that the aortic valve fares very well. So what to do with the arch? We can replace it with a tube graft and address each of the usual three arch vessels. Or we can translocate the whole of the aortic arch vessels permitting the use of either replacement or stenting. As cardiac surgeons, we find ourselves replacing the ascending aorta in an emergency as a life-saving procedure for dissection. We, of course, will look at ascending aortic aneurysms for elective surgery for prognostic issues and this is often in conjunction with other procedures in the chest such as aortic valve replacement,” he said.

Endovascular procedures a valid alternative in selected patients

Piergiorgio Cao, Rome, Italy, speaking on branched stent grafts for the treatment of complex arch lesions, said that any repair of aortic arch remains demanding and exposes patients to mortality and stroke risks that are “not negligible”. Open repair is the gold standard, and hybrid and endovascular repair are valid alternatives, mostly in patients who are at high risk for surgery, he noted.

Cao defined the morphological feasibility to receive endovascular treatment as the presence of a proximal landing ≥2cm in length and ≤4.2cm in diameter. The challenges for TEVAR in the arch include conformability of the stent graft, endoleak and retrograde dissection occurence, he said.

He then alluded to a recent publication in the Journal of Vascular Surgery from Paola De Rango et al that analysed total aortic arch reconstruction in a contemporary comparison of current open and endovascular repair.

De Rango et al entered endovascular and open arch procedures performed from 2007 to 2013 into a prospective database and then retrospectively analysed the data. Endovascular repair (proximal landing zones 0-1), with or without a hybrid adjunct, was selected for patients who were sicker but who had a fit anatomy. Operations involving coverage of left subclavian artery only (zone 2 proximal landing) and open hemiarch replacement were excluded.

As reported in the journal, the authors concluded that despite the older age and a higher comorbidity profile in patients with challenging aortic arch disease who were suitable and selected for endovascular arch repair, no significant differences were detected in perioperative and four-year outcomes compared with the younger patients undergoing open arch total repair.

Yesterday, Cao concluded by saying: “The endovascular approach is a valid alternative to open surgery for all patients, when morphologically feasible. A safer proximal landing zone with longer coverage of the ascending aorta may be the key for long-term durability and to prevent retrograde dissection. Branched stent grafts might be useful in avoiding arch manipulations and decreasing the risk of major adverse events,” he said.

Greenhalgh then commented that the audience might like to have some idea of the expected mortality associated with both the open and endovascular methods in the case of a 70-year-old patient with an ascending dilating disease process in which the valve becomes incompetent. Mortality is 3% with open repair and 10% with endovascular repair, the audience learned.

He further commented on the resurgence of the classification of aneurysmal disease: “The starting point seems to be aneurysmal disease. We are seeing comments on syphilitic, fusiform and saccular aneurysms and this is beginning to look like an old surgical textbook, he commented.

In a debate, Hans-Henning Eckstein, Munich, Germany, argued against the motion “The heyday of open aortic surgery is over” to garner majority support that open repair still had a valid place in the treatment of the ascending aorta and aortic arch. He persuaded 65% of the delegates to vote against the motion. Frank Veith, New York, USA, spoke for the motion.

A clinical trial evaluating Eluvia Drug-Eluting Vascular Stent System (Boston Scientific) has met its primary endpoint with more than 94% of the lesions treated remaining open at nine months post implantation. This was accompanied by a target lesion revascularisation rate of less than 4%.

Results from the MAJESTIC trial were presented yesterday by Stefan Müller-Hülsbeck, Flensburg, Germany, at the CX Abstracts Session – Peripheral Arterial. The trial enrolled 57 patients across Europe, Australia and New Zealand with an average lesion length of 70.8mm. 

“I have not seen clinical data this impressive for a vascular stent that has to perform in an environment as challenging as the superficial femoral artery,” said Müller-Hülsbeck. “Because of forces created by knee flexion, there is an increased risk of restenosis, but we are seeing little evidence of this in the MAJESTIC trial.”

The nine-month follow-up showed no deaths or amputations.

The Eluvia Stent System is a stent purpose-built for the superficial femoral artery and uses a polymer and paclitaxel combination designed to facilitate a sustained drug release to reduce restenosis. The system is built on the Innova Stent System platform consisting of a self-expanding nitinol stent with a paclitaxel-eluting biostable polymer matrix loaded on a low-profile delivery system. According to Boston Scientific, the stent architecture features a closed-cell design at each end of the stent for more predictable deployment, and an open-cell design along the stent body for improved flexibility, strength and fracture resistance.

The Eluvia Stent System is pending CE mark and is not available for use or sale in the USA.

Yesterday, for the first time, the Charing Cross International Symposium broadcast peripheral live cases that were directly linked to data presented the previous day on the theme of peripheral arterial controversies. The aim of the course was to provide delegates with opportunities to learn techniques to achieve the best results with the approaches discussed in the data.

Speaking from Bad Krozingen via satellite video, Thomas Zeller (Bad Krozingen, Germany), the director of the peripheral live cases course, said: “The live case transmissions are little bit different from what people are used to seeing at conferences. Our goal is not to educate or teach you about complex interventions; our goal is to provide you with context to data from recently published trials or even ongoing trials.” He explained that he would be the chief operator in the cases and would be assisted by Alijoscha Rastan, Elias Noory, and Ulrich Beschomer (all from Bad Krozingen, Germany).

The first case of the course was related to the 24-month ILLUMENATE data that were presented on Tuesday at CX by Stephan Duda (Berlin, Germany). It involved a patient who was enrolled in the ILLUMENATE Global Registry, which is evaluating Spectranetic’s Stellarex drug-coated balloon. Zeller explained that the patient appeared to have very mild disease of the distal superficial femoral artery. He added that they had purposely chosen a patient with a “relatively simple lesion” to remind the audience that “almost all of the data you can see so far regarding drug-eluting balloons are TASC A or B lesions”.

Zeller reported that he would be using an 8cm drug-coated balloon (with a 4cm balloon to predilate the vessel) because the rule for using drug-coated balloons should be the same as that for using stents in the coronary arteries: treat from a healthy segment into a healthy segment. He explained that the patient in this case had diffuse disease in proximal areas.

According to Zeller, another rule for using drug-coated balloons was not to put the balloon into the vessel until “everything was prepared”. He said: “Preparation means slashing off the guidewire; it is evacuating cracked air from inside the vessel so that you can see the exact actions of the balloon when it is inflated. If you wait until the balloon is inside the vessel to do the preparation, the balloon is already exposed to the bloodstream; the longer the balloon is exposed to the bloodstream, the more drug you will lose from the surface.”

The second case, in which the Silverhawk atherectomy device (Covidien-Medtronic) and a drug-coated balloon were used to treat a popliteal artery stenosis, was also related to data presented during the peripheral arterial controversies. Zeller commented that the rationale for using atherectomy in this patient was based on the results of the DEFINITIVE AR study, which indicated that directional atherectomy and anti-restenotic therapy (DAART) could be used to improve patency in long and severely calcified lesions: the Zeller himself presented the study’s 24-month results at CX on the peripheral day. However, he commented that the patient in the case was not the typical “DEFINITIVE AR” patient because her femoral artery was “free from disease”. “The popliteal artery, in particular the distal segment, is severely exposed to extra compression forces. Therefore, we usually try to avoid placing a stent in this artery. Thus, we used atherectomy before a drug-coated balloon in this particular patient to try to avoid the need for a stent,” Zeller explained.

Rotational atherectomy, with the Jetstream device (Boston Scientific), and a drug-coated balloon (Ranger, also Boston Scientific) were used, in the third case, to treat a calcified superficial femoral artery lesion. According to Noory, who gave the overview of the case, the first-in-man data for the Ranger device were not yet available but data from the preclinical studies were “promising”. The case sparked a discussion about when to use atherectomy and when to use rotational atherectomy, with Zeller commenting: “Rotational atherectomy is a pretty good tool for occlusions. Also small vessels, 4mm for example, also respond very well to the Jetstream system. If you have larger diameters, 5–6mm vessels, or bifurcations then I prefer to use atherectomy.”

The final case of the morning was supposed to involve the use of the TurboHawk (Covidien-Medtronic) and a drug-coated balloon for the treatment of a lesion in the common femoral artery. This related to the ongoing PESTO-CFA study, which is comparing percutaneous intervention with surgery for the management of common femoral artery lesions. However, Zeller had difficulties putting in the guidewire in the lesion and, after discussing the case with the audience, decided to proceed to putting in the drug-coated balloon without using atherectomy.

In the afternoon, cases were focused on situations in which “stents were unavoidable or beneficial” and “where stents are unavoidable or beneficial and in-stent restenosis treatment”. The devices used in these cases were the Zilver PTX (Cook Medical) with a new release system, the Supera (Abbott Vascular), the Supera with a provisional re-entry device, the Innova  stent (Boston Scientific), the SmartFlex (Cordis), a sirolimus-eluting balloon and the BioMimics stent (Biosensors), heparin-bonded contoured-edge Viabahn (Gore Medical), and Rotarex (Straub Medical) and IN.PACT Pacific (Medtronic). During Tuesday’s peripheral programme, there were talks reviewing the current controversies in peripheral stenting.

Giovanni Torsello (Münster, Germany), who chaired the morning session of the live cases course, said the live cases were a valuable educational tool because delegates not only wanted to hear about study data but also see “how they can make their strategies, their techniques better than before. This is why people attend live case courses.”

LINC@CX

LINC (Leipzig Interventional Course) once again held a live case session at CX, which this year focused on below-the-knee interventions. The cases included recanalisation of an infrapopliteal obstruction with a drug-coated balloon, retrograde transpedal recanalisation with 3F access system, and lesion-specific use of a drug-eluting stent and a drug-coated balloon for an infrapopliteal obstruction. Giancarlo Biamino (Mercogliano, Italy) told CX Daily News that live cases that “do not go according to plan” were just as educational as the ones that did because it gave delegates opportunities to see how operator can manage and rectify unexpected situations.

In traditional Charing Cross fashion, yesterday’s debates stirred much discussion in the Main Auditorium. Particularly stirring was the debate where the audience voted 70% against the motion that EVAR is not sensible for any abdominal aortic aneurysm with a neck length less than 10mm. Stephen Cheng (Hong Kong) spoke for the motion, while Jan Blankensteijn (Amsterdam, Netherlands) sounded-off against the motion.

Making his case, Cheng said that even with new devices, there are more early complications, more late complications, more (difficult) secondary interventions and more adjuncts associated with short-neck endovascular aneurysm repair.

On the other hand, his opponent maintained that in selected cases of infrarenal neck length <10mm, “Any of the current infra/transrenal devices can be used with or without endoanchors for enhancement,” adding that even if it comes with a moderately increased risk of type 1a endoleak, it “balances against downsides of F-EVAR, CHIMPS, or against open repair (if F-EVAR is not an option).”

Discussing the outcome of the debate and the audience’s strong position against the motion, Blankensteijn said, “I think that people understand that things are not absolute and clearly we know that staying inside IFU you get better results. I am not running around proposing to treat any less than 10mm neck with an infrarenal device, but the point is that judicious use of these devices outside IFU can produce better results and injudicious use outside the IFU is an instruction that the industry gives you, we need to think with these device what to do an there are several occasions it does not make sense or it may even be dangerous to use a fenestrated stent graft. Then I would suppose that an infrarenal device (for instance Gore Excluder) preserves all the options juxtarenally, so if this fails, you still have the option to use a fenestrated cuff or go higher up.”

The debate took place during a session on procedures for infrarenal abdominal aortic neck.

The answer lies in the neck

While presenting the morphology findings from the IMPROVE trial, Robert Hinchliffe, London, UK, drew attention to independent association between neck length and mortality. “Only aortic neck length is significantly associated (inversely) with 30-day mortality both for open repair (p<0.001) and overall (p=0.007). The shorter the neck, the higher the mortality after open repair (and EVAR). With long necks, the 30-day mortality from EVAR and open repair is similar (and this is consistent with the results of the AJAX and ECAR trials),” he said.

Therefore, added Hinchliffe, a short aneurysm neck was the commonest reason for a patient being unsuitable for conventional EVAR. The results also explain why observational studies, which cherry pick long-necked aneurysms for EVAR leaving all the short necked aneurysms for open repair, always show that mortality is lower after EVAR. “Such observational studies are comparing apples and oranges,” he said.

The morphology findings could also explain the worse outcomes in women as short aneurysm necks are especially common in women.

“In the future, new, widely available endovascular strategies for rupture in short necked aneurysms are needed and results following rupture should report juxta-renal and infra-renal aneurysms separately,” Hinchliffe said.

“Aneurysm morphology indicates whether a patient with ruptured abdominal aortic aneurysm is eligible for EVAR and may influence the outcome of both EVAR and open surgical repair,” he concluded.

Stick to the IFU

Timothy Resch, Malmö, Sweden, enforced the point that the outcome of EVAR is “excellent if we stick to the IFU and hostile sealing zone anatomy affects the outcome of EVAR negatively both in the short and long term regardless of the device that you use.”

Resch explained that 10—20% of EVAR patients have necks <15mm, and these short infrarenal necks are predictive of initial technical failure, with increased incidence of early and late type 1 endoleak and increased use of intraoperative adjunctive procedures, where the long-term outcome is impaired and endoleaks, migration and late rupture are common.

Referring to a contemporary meta-analysis of 12,000 patients treated with modern devices, 3,039 patients with hostile necks saw an increase in 30-day mortality, intraoperative adjuncts, 30-day migration and an increase in type 1 endoleak at 30 days and one year.

Further, in the ANCHOR registry, Resch noted, a regression and ROC analysis was used to try to find predictive factors for type 1a endoleak which showed that the diameter of the neck correlates with poor outcome, as does the anatomic neck length. “This actually provides some solid data for calculating the risk in the individual patient,” he said.

“So one option of course in these short juxta pararenal aneurysms is to seal higher above and use the fenestrated and incorporate the visceral arteries in your repair. Does that solve the problem of the proximal endoleaks? Again, it depends on how you use the graft,” Resch suggested.

Making a case from some of his own data and that of a study at the Cleveland Clinic, USA. “We found no cases with proximal type 1 endoleaks during long-term follow-up of these patients. So maybe this is the solution for everything—using it in the right context. In a larger series from the Cleveland Clinic analysing over 900 patients with fenestrated grafts, indeed there was a 2.8% incidence of late type 1a endoleak occurring in a steady fashion over time and almost half after a year post-operatively. Looking at the risk factor in that series, what they identified again was a poor sealing zone, just as you would in an infrarenal neck and more that 10% was diameter change and they also found that the sealing zone was much more unstable in the juxtarenal vs. more proximal aorta. So from the clinical perspective, we have learned from that and we now place more fenestrations on the graft to reach a healthy sealing zone, which in our series, combined with the series from Lille with 300 patients, resulted in a higher placement of the endograft than we initially did without affecting the operative mortality or the one-year outcome,” he reported.

The INNOVATION study found that the rate of freedom proximal type I endoleaks and the rate of freedom from reintervention in patients who underwent endovascular aortic aneurysm repair (EVAR) with the Incraft (Cordis) device was, respectively, 100% and 95%, at three years. In this interview, CX Daily News speaks to Giovanni Pratesi (Florence, Italy)—who presented the data at CX yesterday—about Incraft and the three-year results.

How does the Incraft stent graft differ from other EVAR devices?

It is a new-generation stent graft system with unique features that have been specifically designed to overcome the limitations of current stent grafts. For example, the ultra-low profile integrated delivery system (14F OD) offers excellent navigational opportunities in challenging access vessels. Additionally, the micrometric deployment system allows for accurate placement—either at proximal and distal attachment site. Bilateral in-situ length adjustment, up to 3cm, permits you to customise every implant on the single patient anatomy. Therefore, the Incraft system, according to the “few-fits-most” concept, is able to cover a large spectrum of anatomies with only 23 product codes, four main bodies and 19 iliac limbs.

What are the main results of the INNOVATION study at three years?

The three-year results of the INNOVATION study have confirmed the very promising one- and two-year outcomes of the study. These data show, at three years, the device is associated with 100% freedom from type Ia and III endoleaks, stent-graft migrations, and device- or procedure-related major adverse events. They also show that the rate of limb patency is 97.8%, with only one case of limb occlusion. Other findings from the three-year data indicate that there is a significant reduction in mean aortic aneurysm diameter, up to 15 mm, compared with two-year data, a freedom from sac increase of 95.6% and freedom from stent fractures of 97.7%. Core lab analysis has identified two cases of aneurysm sac enlargement—both associated with a persistent type II endoleak—and one case of stent fracture, but these events did not appear to have any clinical consequences.

What other data were included in your presentation?

I specifically addressed endograft durability and anatomical preservation in my analysis of the Innovation study. Data from core lab analysis have confirmed the excellent stent graft stability that has already been observed during follow-up. A median proximal migration of 2mm was observed at three-year compared with the one-month computed tomography (CT) scan. The same result was achieved in terms of distal migration with a median change of 1.1mm and 2mm on the right and left side respectively, compared with the one-month CT scan.

Aortic neck diameter, neck angulation and iliac artery diameter, compared with one-month CT scan, were analysed at three years to review endograft influence on anatomic changes during follow-up. The observed 1mm proximal neck dilatation and 2mm iliac artery dilatation, combined with the 0.6 degree changes for infrarenal neck angulation and 2.4 degree for suprarenal neck angulation, confirmed the excellent stent graft conformability to the preoperative anatomy.

What were the main take-home messages from your presentation?

These data confirm the very promising earlier outcomes of Incraft stent graft system and add new evidence regarding its effectiveness in terms of anatomy preservation with a 100% freedom from both proximal aortic neck and iliac dilatation, and from proximal supra- and infrarenal aortic neck angulation changes.

Yesterday saw the beginning of the two-day CX Venous Workshop, in which delegates can enjoy expert demonstrations of a selection of the most interesting and important phlebological technologies currently in use. Now in its seventh year, the event continues to attract more and more delegates to its plethora of new and established technologies, and this year occupied its largest space ever on the Upper Level of the Gallery. The first day of the workshop largely focused on varicose vein treatment and superficial venous issues.

Ian Franklin (Imperial College, London, UK) is leading the workshop over both days, and has done since it first featured at the Charing Cross Symposium seven years ago. He explained, “I think it is important to provide a combination of the big plenary sessions in the hall and smaller interactive workshops like this one—not all techniques and discussions lend themselves the plenary environment. By providing these training stations and this small-group one-to-one teaching format, it means that people can interact in a much more informal, personal level.”

Over its seven years the workshop has grown and changed, keeping pace with the changing face of the vascular field. “The needs have changed,” Franklin commented. “When we first started doing this it was an office-based varicose vein course. Now it is far more than that. We have found that quite a lot of the techniques that people were hungry to learn at the beginning are ‘old hat’ now, so each year we offer new things. Now people are hungry to learn deep vein stenting, intravascular ultrasound, non-thermal techniques for treating veins, and so on. This year we have some completely new things that people will not have seen before.”

Given the quality of the Charing Cross faculty, such one-to-one interaction presents an exciting educational opportunity. “All of our faculty are well-known names and enthusiasts in their field. You can interact with them much better if you talk to them face-to-face rather than if they are up on a podium and you are down in the audience and asking the questions through a microphone. This way you can ask things you might not be able to go into in a lecture theatre.” Franklin added that these face-to-face interactions combine with practical experience, and delegates can “hold the kit in their hands, practice on the simulator and talk through tips and tricks with someone who has done it a lot before—you cannot do that in a lecture theatre.”

The workshop’s layout with multiple training stations also means that delegates can be efficient with their time, heading straight for those stations dealing with subjects they are unfamiliar with. “They do not have to sit through things they already know about, so they can make very efficient use of their time,” Franklin said.

The workshop features both established and new technology. One of the busiest stations yesterday was that of a well-established technology—foam sclerotherapy.  Simon Ashley (Plymouth, UK), was one of the trainers at the station. He spoke to CX Daily News during the workshop, and explained, “Personally it is the first time that I have been involved as a trainer, but I know that it has been running for a number of years and has grown increasingly popular—that is why so much space has been devoted to it.” As to why the station was so busy, Ashley noted that foam sclerotherapy “is a walk-in walk-out treatment that only takes about 20 minutes and there is no down time or restriction of activities afterwards. It is also very attractive for NHS and private practice because it is undoubtedly the most cost-effective treatment.”

In keeping with the Charing Cross Symposium’s passion for innovation, there was also a selection of new techniques and products on show. The Biolas station, exhibiting the company’s non-thermal ablation VariClose vein sealing system, was kept busy throughout the day by curious delegates. The company are attending their first ever Charing Cross Symposium, and chief medical officer, Yunus Çakiroĝlu, told CX Daily News “We are new this year, so I think a lot of people are wondering about our products and our company—they want to find out who we are and what we have at our station. The meeting is very exciting, and the workshop is a great way for the delegates to understand new technology.”

The workshop will continue today with a focus on acute deep vein thrombosis interventions, intravenous ultrasound and deep venous stenting, but still including ablation technologies for superficial veins. The stations open for delegates to visit will include: thermal (laser), thermal (radiofrequency ablation), non-thermal, practical training stations, valves, vascular ultrasound training simulator, venous malformations, pelvic venous imaging, pelvic vein embolisation, acute deep vein thrombosis, caval filters, follow-up protocols, air plethysmography, intravascular ultrasound and deep vein stenting.

Franklin expects the Upper Gallery to be just as busy as it was yesterday thanks to the planning of this year’s programme. He said, “We have made an effort to separate the days this year, with Wednesday focusing more on superficial techniques. On Thursday we are going to have a big focus on deep vein stenting, deep vein thrombosis treatments, pelvic vein embolisation and intravascular ultrasound. These are all quite new for us and should attract a new group, so I expect it to be busy tomorrow as well.”

According to Janet Powell, Imperial College London, UK, the highest risk factors for rupture of abdominal aortic aneurysms (AAA) are female gender, smoking, increasing age and mean arterial pressure, but there are still few useful indicators of how to manage screen-detected aneurysms to stop them enlarging. Powell put forward this view during yesterday’s Abdominal Aortic Controversies Main Programme which explored epidemiology, indications and medical management of abdominal aortic aneurysms.

In trying to work out what makes aneurysms grow, Powell said that mostly the “mundane” cardiovascular risk factors have been looked at—alcohol, diet, obesity, smoking, medicines taken, exercise taken.

Turning to the existing and ongoing randomised trials that provide evidence for growth factors, Powell pointed out three trials already completed and without a positive result—AAA:STOP, PHAST and AORTA.

“Even in 2015, it is quite difficult to find information about trials because some trials still remain unregistered. Large epidemiological studies have mainly shown us about the risks for developing aneurysms, but the focus has been on baseline risk factors, not aneurysm progression,” she said.

Powell referred to RESCAN, a large international project primarily with the purpose of looking at optimal surveillance intervals for small aortic aneurysms, which was an individual patient data meta-analysis of small aneurysms, their growth and rupture in more than 15,000 persons.

“As we all know, growth rate increases with aortic diameter—just 1.34mm a year for the smallest aneurysms and 3.63mm when it comes to 5cm aneurysms—with exactly the same growth rate between men and women,” she pointed out.

When it comes to smoking, Powell maintained that the data are remarkably consistent that it increases aneurysm growth rate but that the effect is modest. Similarly, the effect of diabetes to slow or reduce the aneurysm growth rate is very consistent, but small.

“So we identified out of the available baseline data we had only two factors in these 15,000 patients that influenced growth rate and both effects were relatively modest—smoking increases, diabetes decreases. Cholesterol, blood pressure, statins, anti-hypertensive drugs and aspirin had no effect, and the year of enrolment [1985–2008] had absolutely no effect either. Disappointing,” Powell stated.

Rupture rates

Even though rupture of small aneurysms is not common, findings were more informative. RESCAN showed that the smallest of aneurysms take eight or more years before the risk of rupture is anything substantive, but as the diameter increases, so does the risk of rupture. But even for a 5cm aneurysm, it is more than year before risk of rupture exceeds 1%.

Powell pointed to some strong associations with factors that increase rupture rates. “Most notable, the fact that in women, there is fourfold increase in rupture rates vs. men. With smokers there is a twofold increase, with a far bigger effect on rupture than on growth. Mean arterial pressure increases growth rate, as does age. The older you are, the more likely your aneurysm is to rupture for any given diameter. So we cannot have any of this ageism, we need to treat aneurysms in older people too,” Powell maintained.

In the EVAR 2 trial, and subsequently reproduced in other papers, Powell observed that aortic neck length was associated with rupture and the shape of the aneurysm might have mattered, and a long neck was associated with relative protection from aneurysm rupture.

“Where are we in 2015? For rupture, there are some strong factors increasing risk: female gender, smoking (which we can do something about), increasing age, higher mean arterial pressures (we could have more effective blood pressure control), and the fact that a long aneurysm neck could just be protective. However, for growth, the effects that we have identified are modest: smoking, which increases it, and diabetes, which is protective,” Powell said.

She re-stressed that both of those growth effects are modest, adding that, “unfortunately this leaves us in a position that as yet we have few useful indicators of how to manage screen-detected aneurysms to stop them enlarging other than the old classic that was used for intermittent claudication—stop smoking and possibly keep walking.”

Results from the 12-month data of the randomised controlled IMPROVE trial, presented for the first time at CX 2015 (28 April–1May, London, UK), show that an endovascular strategy is cost-effective when compared to open repair in the treatment of ruptured abdominal aortic aneurysms. The one-year data also revealed that the endovascular strategy conferred no survival benefit over open repair, except a trend towards benefitting women. It also showed that the endovascular strategy enabled more patients to be discharged from hospital to home, and significantly faster than with open repair. Patients also have an excellent quality of life with endovascular strategy, if they survive the rupture, delegates heard.

Twelve-month outcomes from the individual patient data meta-analysis of three randomised controlled trials of ruptured aneurysms [ie the Dutch AJAX trial, the French ECAR trial and the UK IMPROVE trial] also showed a trend towards survival benefit for endovascular aneurysm repair (EVAR), but this was not statistically significant. A CX audience poll in the session revealed that nearly 80% agreed that the 12-month results of the IMPROVE trial encouraged them to perform EVAR more often.

Janet Powell, Imperial College, London, UK, presented the latest data from the IMPROVE (Immediate management of the patient with rupture: Open vs. endovascular repair) trial that reported one-year outcomes following either a strategy of endovascular repair first or open repair of ruptured abdominal aortic aneurysm. The results demonstrate no survival benefit for the endovascular strategy for ruptured aneurysm at one year. However, an endovascular-first strategy for the management of ruptured aneurysms does offer patients faster discharge with better quality of life and it is also cost-effective. Both these factors are necessary for patient and clinical decision-making, delegates heard. These data were published in April in the European Heart Journal (EHJ).

IMPROVE, a pragmatic, multicentre (29 UK and one Canada) trial randomised 613 patients with a clinical diagnosis of ruptured aneurysm, 316 patients to an endovascular-first strategy (if aortic morphology was suitable and open repair if not) and 297 to open repair. Powell also drew attention to the fact that at baseline, the characteristics of the two groups were similar with almost three-quarters in each group being men. “The aneurysms in this trial were also very large with average diameters in each group being over 8cm,” she said. The principal one-year outcome was mortality and secondary outcomes were reinterventions, hospital discharge, health-related quality-of-life, costs, quality-adjusted-life-years and cost-effectiveness.

At CX 2015, Powell noted that the trial was designed to answer the question of what to do with a patient who presents to the emergency room with a diagnosis of ruptured abdominal aortic aneurysm. “What we had anticipated was that using an endovascular strategy, wherever it was morphologically feasible, we could reduce 30-day operative mortality from 47% in the open repair group to 33% where endovascular repair was used extensively,” she said.

Powell added: “At one year, all-cause mortality was 41.1% for the endovascular strategy group and 45.1% for the open repair group (p=0.325) with similar reintervention rates in each.  A subgroup analysis showed a stronger benefit for the endovascular strategy in women versus men. The endovascular strategy group and open repair groups had average total hospital stays of 17 and 26 days, respectively.

The 30-day mortality results, the primary outcome, previously published in British Medical Journal (BMJ) in 2014, also found no difference in 30-day mortality between the endovascular strategy group and the open repair group and subgroup analysis showed a strong benefit for the endovascular strategy in women compared with men.

Pooled individual patient data outcomes

Ron Balm presented the 12-month outcomes meta-analysis from the individual patient data from the three randomised controlled trials of ruptured aneurysms; the Dutch AJAX trial (Annals of Surgery 2013), the French ECAR trial (EJVES 2015) and the UK IMPROVE trial.

“These were all trials that were performed on patients with a clinical suspicion of ruptured aneurysm. In the AJAX trial the 30-day mortality in both groups was approximately 25%, in ECAR it was 22% and in IMPROVE, which had a slightly different study design, it was 35% in each group (BMJ 2014), but all failed to demonstrate the benefit of EVAR in the emergent setting. “The results were hampered by the fact that open repair performed so much better than we expected,” Balm noted.

The pooled inpatient data was subjected to two different analyses; the first was an analysis as randomised including all patients and the second contained only those patients with proven rupture and a restricted cohort from the IMPROVE trial who were anatomically suitable for EVAR.

“The 30-day survival data showed no significant benefit for endovascular repair. A subgroup analysis of age, sex and Hardman disability index showed that age and Hardman index had no influence on the main results, but female sex was identified as benefitting from endovascular repair. The time to discharge alive from primary admission was also significantly better for patients undergoing EVAR when compared to those undergoing open repair. We also looked at the influence of neck diameter, neck length and neck angulation. Longer neck lengths resulted in better survival for all patients,” Balm said.

In the pooled results of all patients, the three-month mortality rate included only those patients who were fit for endovascular repair, which reduces the patients in the IMPROVE trial. There seems a benefit for endovascular repair but this is statistically not significant, he said.

Summarising the survival results of all pooled patients to one year, Balm said, there is an advantage for EVAR, but this is statistically not significant. 

These findings led Balm to conclude that the early data from the pooled inpatient data meta-analysis did not suggest that there was any survival benefit for EVAR. “At one year, the small survival advantage of EVAR is not significant. Yet, although endovascular repair does not offer a significant survival advantage, endovascular repair should be used more widely. Open repair must remain available for those unsuitable for conventional EVAR,” Balm maintained.

Are patients with ruptured aneurysms being turned down too often?

A small majority of voters, 57%, did not agree with the motion “Too many patients with ruptured aneuryms are denied intervention” in an interesting debate on the topic.

Matt Thompson, London, UK, speaking for the motion, based his arguments on the data from Karthikesalingam et al (The Lancet, 2014), which used UK Hospital Episode Statistics (HES) data and US Nationwide Inpatient Sample (NIS) data to show that in-hospital survival from ruptured abdominal aortic aneurysm, intervention rates, and uptake of endovascular repair are lower in England than in the USA.

Thompson stated that 68% of patients in the UK receive no treatment for rupture. “There is a huge variation in the proportion of patients being offered therapy for ruptured abdominal aortic aneurysm at the regional and international level. Non-interventional treatment is universally fatal,” he said.

Thompson argued that apart from identifying the optimal management strategy for patients with ruptured aneurysms, more emphasis should be placed on treatment rates. “We must do better than refuse treatment to around 60% patients,” he said.

Peter Lamont, Bristol, UK, who persuaded the delegates that ruptured aneurysm patients were not being denied interventional treatment too often, contested the data presented by Thompson because with the HES data it made the assumption that the diagnostic code for ruptured abdominal aortic aneurysm without an operative code for the condition was a turndown. He also pointed out that a 2005 coding audit had found up to 23% HES codes to be incorrect. Further, NIS data misses 80% of patients, noted Lamont.

“Numerous direct audits in 2010 and after in the UK show consistent turndown rates of around 20% by vascular surgeons,” he said.

Lamont pointed to a Vascular Society members audit in 2011 that revealed a turndown rate of 24% and also showed that the average age of patients was 83. “Of these, 24% declined intervention, 14% had dementia and 21% had terminal malignancy/severe chronic disease,” he added.

Lamont concluded by saying that the service reconfiguration in the UK guarantees that vascular surgeons are now on call 24/7 for ruptured abdominal aortic aneurysm. “When comparing like for like, the turndown rates in the UK are similar to those in the USA,” Lamont said.

In the ensuing discussion, Powell made the point that twice as many women than men are turned down for treatment when they present with ruptured aneurysm and asked for a response on why this might be the case. “We did not formally address that in the IMPROVE trial, but there are several observational cohorts to suggest that adopting a more minimally invasive approach would lead to a reduction in turndown rates in these patients,” added Thompson.

Thompson explained the criteria for palliation; patients in whom intervention is completely futile, such as those with advanced malignancy or dementia, who have no quality of life are suitable candidates for palliation. “There are patients in whom it is cruel to intervene as they do not want their life prolonged,” agreed Lamont.

Frank Veith, New York, USA, made the point that the way to decrease the turn down rate for ruptured aneurysms was to embrace endovascular repair.

The use of bioresorbable scaffolds is the only complete solution for the superficial femoral artery, argued Andrew Holden, Auckland, New Zealand, in yesterday’s Peripheral Arterial Controversies session.

Presenting an update on the Stanza programme, Holden told delegates that the ideal treatment strategy for superficial femoral artery disease has been the source of much research, discussion and controversy. “An endovascular device should provide vessel support acutely to manage dissection and recoil, include an anti-restenosis strategy and preferably leave nothing behind when no longer needed. A bioresorbable drug-eluting scaffold potentially fulfils these requirements,” he explained.

The programme employed the Stanza platform (480 Biomedical)—a flexible, self-expanding stent design with full resorption in about 12 months. Holden summarised the development of the Stanza scaffold, the first part of which—the STANCE first-in-man trial—allowed “assessment of stent parameters such as precise positioning and deployment, excellent radial resistive force with minimal residual stenosis and satisfactory resorption.”

Two sub-studies in the STANCE trial allowed original validation of important imaging modalities by independent core laboratories. One sub-study analysed the accuracy of quantitative vessel analysis of magnetic resonance angiography (MRA) compared to the gold standard catheter angiography. A second sub-study compared cross sectional luminal area evaluation using MRA and optical coherence tomography (OCT). This comprehensive analysis, Holden explained, confirms MRA is “an effective method to assess the vessel lumen non-invasively after treatment with a bioresorbable scaffold.”

The study showed 100% scaffold delivery success, good scaffold apposition verified by optical coherence tomography (OCT) and angiography, and acute performance similar to metal stents. Holden noted that OCT is a vital tool in the assessment of bioresorbable scaffolds, as it allows investigators to identify scaffold encapsulation during healing and resorption. Using OCT Holden was also able to create 3D reconstructions of the vessel, allowing him to detect any scaffold fractures and show that at six months the scaffold demonstrated chronic strength to prevent vessel recoil.

The drug-eluting version of the Stanza platform is currently being assessed in the SPRINT clinical trial. Holden told attendees that the biggest challenge has been to define appropriate and extended drug release kinetics to deal with the inflammation associated with scaffold resorption. This has been achieved with the drug eluting version of Stanza. Currently, there is ongoing recruitment and evaluation in this trial, as well as several examples with medium-term follow-up.

In one such case study, pre-implant the patient had 88% stenosis, a figure which fell to just 2% residual stenosis following the implant. Similarly, in the second case that Holden presented, the pre-implant stenosis figure was 92%, falling to 0% following the implantation of Stanza. Both of these case studies were evaluated with MRA and OCT to confirm the outcomes.

Twelve-month results from the randomised, multicentre DEFINITIVE AR pilot study suggest that there is a benefit to adding directional atherectomy in long and calcified lesions prior to using a drug-coated balloon in comparison to the use of a drug-coated balloon alone. Data from the trial were presented yesterday by Thomas Zeller, Bad Krozingen, Germany, who is a study principal investigator alongside Gunnar Tepe, Rosenheim, Germany.

DEFINITIVE AR was designed to assess the effect of treating a lesion with directional atherectomy (Medtronic/Covidien’s SilverHawk or TurboHawk plaque excision systems) followed by a paclitaxel-coated balloon (Bayer HealthCare’s peripheral paclitaxel-coated angioplasty catheter with Paccocath Technology), collectively referred to as DAART (directional atherectomy + anti-restenotic therapy), in order to generate early hypotheses for further research in this therapy area.

Claudicants (Rutherford clinical category 2–4) with 7–15cm superficial femoral and/or popliteal lesions were randomised 1:1 to either DAART (n=48) or to the paclitaxel-coated balloon alone (n=54). Patients with severely calcified lesions were assigned to a non-randomised registry arm and were treated with DAART (n=19). Baseline patient and lesion characteristics did not differ between the DAART and drug-coated balloon arms. 

Technical success, defined as ≤30% residual stenosis following the protocol-defined treatment at the target lesion, was significantly higher in the DAART arm vs. the drug-coated balloon arm (89.6% vs. 64.2%, p=0.004). According to Zeller, there were significantly fewer flow-limiting dissections reported in patients treated with DAART vs. drug-coated balloon alone (2% vs 19%, p=0.01). Technical success in the DAART registry group was 84.2% and incidence of flow-limiting dissections was 0%.

At 12 months, per cent stenosis in the randomised groups was 33.6±17.7 for the DAART arm vs. 36.4±17.6 for the drug-coated balloon arm. Duplex ultrasound patency (PSVR ≤2.4, without target lesion revascularisation) was 93.4% for the DAART arm and 89.6% for the drug-coated balloon arm. Angiographic patency (≤50% stenosis and without target lesion revascularisation) was 82.4% in the DAART arm and 71.8% in the drug-coated balloon arm. In the DAART cohort lesions with a residual stenosis <30% post atherectomy did show a trend towards better angiographic patency at one year (94.1% vs. 68.8%).

“This rigorously performed pilot study suggests an added benefit for DAART over drug-coated balloons alone in long and calcified lesions. Further investigation in larger, prospective, statistically-powered randomised trials is warranted. Patients will be followed out to 24 months to assess durability of the results,” Zeller said.

At this year’s Charing Cross Symposium, Cordis is launching the Outback Elite re-entry catheter, an enhanced version of the Outback re-entry catheter that received the CE mark earlier this week. According to the company, Outback Elite provides more control and precision and includes additional features to enable re-entry into the most complex lesions whilst facilitating positioning and delivery.

Yesterday, Thomas Zeller, Bad Krozingen, Germany, a user of the Outback re-entry catheter, spoke to CX Daily News about his experience with the device and his expectations about this new iteration.

Amongst the new features of Outback Elite are single-handed torque and deployment—the torque control is located closer to the needle actuator and the longer handle provides a more efficient slider mechanism—a robust nitinol cannula for re-entry in very complex lesions and a lubricious hydrophilic coating to help delivery.

In addition, the Outback Elite is available in a 120cm shaft length as the previous catheter but is also being launched with an 80cm shaft length indicated for ipsilateral antegrade or iliac procedures. The new size offers the advantage of having less shaft length to handle outside of the patient, increasing precision on the re-entry site.

The Outback Elite follows the successful performance of the Outback catheter. In a randomised controlled trial by Roberto Gandini et al comparing re-entry with Outback vs. manual re-entry in chronic total occlusions in the superficial femoral artery, the device achieved 100% re-entry rate vs. 42.3% with the manual re-entry technique. It also showed shorter procedure and fluoroscopy times.

Kristen Rock, global product director at Cordis, told CX Daily News, “Outback Elite’s ergonomic handle and added shaft sizes provide physicians with more control, meaning they can easily pinpoint exactly where they want the re-entry site to be.”

The Outback re-entry device will be used in a live case today at the CX Live Peripheral Arterial Cases – SFA and popliteal in the Grey Learning Centre.

Drug-coated balloon technology is unlikely to be a successful “stand alone” treatment for the majority of medium and long length superficial femoral artery lesions, the voting results from CX2015 implied. The voting showed that the audience felt that drug-coated balloon use was best suited to short lesions. The randomised controlled trial data for drug-coated balloons are mostly based on short lesions and 57% of the audience voted “no” to the question, “Is drug-eluting balloon technology likely to be a successful standalone treatment for the majority of medium and long length superficial femoral artery lesions?” The session in which the vote was held was titled “Leaving nothing behind” and also saw the presentation of the ILLUMENATE first-in-human study 24-month results. These were favourable for the Stellarex drug-coated balloon (Spectranetics), and came close on the heels of updates on the Lutonix drug-coated balloon (Bard) and the IN.PACT Admiral drug-coated balloon (Medtronic). Atherectomy as a pretreatment also received a boost.

For the first time, CX voters also found support for atherectomy, but as a pre-treatment to the use of drug-coated balloons as described in the DEFINITIVE AR trial or as a pre-treatment to the use of stents. The majority, 77%, supported the motion “pretreatment of superficial femoral artery lesions before drug-coated balloon has CX 2015 audience support.

Thomas Zeller, Bad Krozingen, Germany, explained that “Drug-coated balloons add benefit to the endovascular approach to treat femoropopliteal disease but that there are still limitations such as recoil, calcium and dissections.”

Previous research has shown that circumferential calcification is a negative predictor for successful outcome with drug-coated balloon angioplasty. “Directional atherectomy is one of the most interesting pretreatment plaque modulating or plaque removing options available, after cutting or scoring balloons have been shown not to be very effective at this. The removal of ex-centric plaque and calcified plaque serves to reduce the problem of early recoil that limits the use of drug-coated balloon angioplasty outcome,” he said. Zeller also noted that the large majority vote favouring the use of atherectomy as a pretreatment were akin to a mandate to the industry to support large-scale randomised controlled trial to prove this concept.

In previous years, atherectomy has failed to elicit CX voter backing as a definitive treatment option in the superficial femoral artery. In 2014, 57% of the CX audience voted “no” to the motion, “I would use atherectomy for some superficial femoral artery lesions”. In 2013, 68% voted against the motion “atherectomy is the answer for the superficial femoral artery technology”.

This year’s vote shows that there is increasing support for atherectomy as a pre-treatment option rather than a definitive treatment and that the technique is clearly currently in favour of being used prior to drug-coated balloon or stents in order to reduce the risk of thrombosis. A member of the audience asked whether atherectomy should be the first option for isolated popliteal lesions considering there was a desire to leave nothing behind. Zeller, responding, said that it was frequently observed that isolated popliteal lesions were focal calcified lesions and for that indication, he considered atherectomy “an excellent first option followed by angioplasty or stenting”. “However, if we are talking about evidence to support this, there is none,” he clarified.

CX delegates at the session also heard updates on the Stanza bioresorbable scaffold (480° Medical) and Shockwave Lithoplasty for calcified artery from Andrew Holden, Auckland, New Zealand.

ILLUMENATE

Stephan Duda, Berlin, Germany, presented the results of the 24-month ILLUMENATE first-in-human study. These showed that the primary patency rate (as measured by Duplex Core lab evaluation) was 80.3% at 24 months. At 12-months, the primary patency rate was 89.5%.

“The freedom from clinically-driven target lesion revascularisation rate (as determined by the clinical events committee adjudication) was 85.8% at 24 months and it was 90% at 12 months,” Duda said.

In the study, researchers evaluated Stellarex in 50 patients with 58 lesions in a cohort that required predilatation with an uncoated balloon before the inflation of the drug-coated balloon. The mean age of the cohort was 69 years. The mean age of patients was 69.0±9.3 years; Thirty four per cent of patients had diabetes and 80% had hypercholesterolemia; Eighty six per cent were Rutherford Class 3 at baseline; the mean lesion length was 7.2cm; nearly 14% had severe calcification and the mean stenosis at baseline was 75%.

The vessel patency was associated with a significant and sustained functional improvement as resulted by the walking impairment questionnaire and by the treadmill test patient subset. There were no cardiovascular deaths or amputations reported throughout the 24-month follow-up schedule in this cohort, demonstrating the high safety profile,” Duda said.

He continued: “This study demonstrates the safety and efficacy of Stellarex for the treatment of femoropopliteal disease up to two years. The primary patency of 89.5% and 80.3% match the highest benchmark of reported rates at one- and two-years respectively. There is also significant functional benefit observed with improved walking distance, observed up to two years.”

Duda told CX Daily News: “Stellarex employs a next-generation manufacturing technology and coating formulation.  This combination allows for an effective dose of paclitaxel to be transferred to the treatment site using a low drug dose density of 2µg/mm².  Pre-clinical work has shown this coating results in high coating stability with limited drug loss and an effective amount of drug in the arterial wall through 28 days.”

There is a robust clinical programme for Stellarex that is actively underway and will include up to 1,300 patients in five studies, Duda concluded. 

IN.PACT SFA clinical trial update

Gunnar Tepe, Rosenheim, Germany, presented the 12-month results from the pivotal randomised trial evaluating the safety and effectiveness of the IN.PACT Admiral drug-coated balloon.

“IN.PACT SFA is a rigorously designed trial that provides level I clinical evidence supporting the safety and effectiveness of the IN.PACT Admiral when used to treat lesions in the superficial femoral and proximal popliteal arteries,” Tepe said. 

The trial is a prospective, randomised, international, 57-site trial comparing the outcomes of treating a lesion with the paclitaxel-coated IN.PACT Admiral vs. standard percutaneous transluminal angioplasty using an uncoated balloon. 

A total of 331 patients with claudication or rest pain (Rutherford clinical category 2–4) with single de novo or non-stented restenotic lesions ≥4cm and  ≤18cm or chronic total occlusions ≤10cm were randomised 2:1 to drug-coated balloon (n=220) or angioplasty (n=111). Data was independently evaluated by blinded duplex ultrasound and angiographic core labs and by a blinded clinical events committee.

Tepe said: “Baseline clinical, angiographic and lesion characteristics were well balanced between treatment groups. Mean lesion length was 8.94±4.89cm in the drug-coated balloon arm vs. 8.81±5.12cm in the angioplasty arm (p=0.815), representing the longest lesions evaluated to-date in a randomised drug-coated balloon trial.”

A total of 59.3% of lesions in the drug-coated balloon arm were calcified vs. 58.4% in the angioplasty arm (p=0.097), and 25.8% of lesions in the drug-coated balloon arm were total occlusions vs. 19.5% in the angioplasty arm (p=0.222).

“At 12 months, primary patency in the drug-coated balloon arm (freedom from clinically-driven target lesion revascularisation and freedom from restenosis as determined by duplex ultrasound PSVR≤2.4) was superior to the angioplasty arm (89.8% for the drug-coated balloon vs. 66.8% for the angioplasty arm, Kaplan-Meier analysis at day 360 showed that  p<0.001). Clinically-driven target lesion revascularisation was statistically lower for the drug-coated balloon arm vs. the angioplasty arm (2.4% vs. 20.6%, p<0.001). Regarding clinical endpoints, we can conclude that patients treated with IN.PACT Admiral perform more favourably than angioplasty in terms of quality of life and walking capacity and angioplasty treated patients require 88% more interventions to achieve the same clinical outcome,” Tepe said. 

“Patients are being followed out to five years post-procedure and two-year data are forthcoming,” Tepe concluded.

Lutonix update