More vascular and endovascular controversies at Charing Cross

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The 28th Charing Cross International Symposium returns this year promising more high-profile debates and controversies from a world class faculty of the leading endovascular and vascular specialists.

Many of the controversial topics that arose from the 2005 meeting will be thrashed out in a series of head-to-head debates, where speakers and delegates alike will challenge the available evidence in order to reach a consensus. The new format for 2006 will encompass all relevant interventional/imaging/ endovascular topics right through to the latest developments in classical vascular surgery. The first two days of the meeting incorporates the Global Endovascular Forum (see page 4) and will focus exclusively on interventional and endovascular subjects, while the remaining two days will concentrate on classical vascular surgery, entitled, “More Vascular and Endovascular Controversies.”

The great debates

The first great debate begins on Monday morning with abdominal injuries and will highlight when angioembolisation should be used, if at all, in stopping bleeding of abdominal organs. The concept of angioembolisation has been with us for approximately 30 years and has been found to be particularly helpful in the bleeding spleen.

More recently, angioembolisation of the kidney has received support, and in that sense Dr Tony Nicholson, Leeds, UK, will draw attention to the fact that the majority of the blood to the liver is provided through the portal vein, and that bleeding of the liver can be most easily arrested by embolisation in the hepatic artery.

“It will be important to listen to the arguments of Nicholson and Professor Mehmet Kurtoglu, (Istanbul, Turkey) very carefully indeed, and the debate is set up to recommend one or the other.” Professor Roger Greenhalgh, Imperial College, UK, told Vascular News, “It is plain that Kurtoglu would be inclined to use partial embolisation, and it would be important to decide whether partial embolisation should play a role and how much of a role it should play in deciding when a surgical correction of bleeding should be scheduled. These are the key issues and should come out well in the head-to-head debate.”

The second debate will assess the best treatment for varicose veins in 2006, and how reflux is best achieved. The proponents of an endovascular method of various types, Dr Thomas Proebstle, Heidelberg, Germany, and Dr Michel Perrin, Chassieu, France, will claim that the durability and success of the procedure in the long term will follow the more expert durable abolition of reflux in their patient series. This standpoint will be opposed by Mr Prakash Madhavan, Dublin, Ireland, and

Mr Alun Davies, London, UK. “This could be an exciting debate; for years, surgery held the pole position, but it is certainly under threat as at recent meetings there have even been calls for venous reconstruction to be performed exclusively without surgery. It will be interesting to note how the audience finishes up votes after this discussion.”

It is a matter of great interest that the management of iliofemoral venous thrombosis is different in different parts of the world. Historically, continental Europe has practised intervention for iliofemoral venous thrombosis much more commonly than, for example, in Britain and many parts of the USA. Now the whole subject seems to be under review, and the arguments for intervention or conservative treatment should be rehearsed again and the evidence assessed. “The debate entitled, ‘Endovascular intervention for iliofemoral venous thrombosis is the gold standard’, promises to be an enthralling debate and we are extremely grateful to Drs Michael Silva, Cleveland, and Anthony Comerota, Toledo, USA, for the arguments and look forward to their debate with great interest.”

The belief that large-scale population screening of men for abdominal aortic aneurysm will reduce the number of premature deaths is not beyond doubt, and Mr Brian Heather, Gloucester, UK, will argue that “Ultrasound screening of abdominal aortic aneurysms will largely abolish surgery for ruptured aneurysm”. Heather claims data from the Gloucester Aneurysm Screening Project shows that the vast majority of leaking aneurysms will in many cases be an issue of the past and it is just a question of time while the aneurysms discovered are operated on. However, Dr Mario Lachet, Zurich, Switzerland, will argue that this is an issue of cost-effectiveness and that AAA-screening is simply too expensive to save one particular life in this manner.

EVAR debates

The interpretation of the EVAR 1 and DREAM trials, and whether public opinion has moved towards or against endovascular repair where it is possible, is the subject of the next debate.

The enthusiasts for EVAR are Professor Peter Harris, Liverpool, UK, and Professor Krassi Ivancev, Malm̦, Sweden, while those with question marks are Professor Jan Blankensteijn, Nijmegen, The Netherlands, and Mr Richard Gibbs, London, UK. The interpretation of EVAR 1 and DREAM is of great interest, and will very much depend upon the outcome of cost-effectiveness studies. The factors that determine whether EVAR has a long-standing place in management are well known. First, it is clear that the costs of the stent graft devices must not increase substantially. Second, it is important that the companies manufacturing them concentrate on device modification to reduce the need for such high-level surveillance and for reintervention. It can be fairly confidently predicted that it will be necessary for the price of the devices to be kept low and for the reintervention requirements to be reduced before endovascular aneurysm repair can be expected to be cost-effective. “The claim that there are some patients who will do better with open repair has been suggested but not proved. I would like to thank the speakers that the positions they have taken in these debates are not necessarily the views they hold, but the views they have been asked to argue,” he added.”It was Professor Janet Powell, London, UK, who, upon seeing the EVAR data, remarked that focus should move towards improving fitness rather than performing EVAR early,” said Greenhalgh. Therefore the next debate is designed to test Powell’s statement, which was made very much ‘off the cuff’. Dr Kenneth Ouriel, Cleveland, USA, will state that before the EVAR 2 trial, the expectation was to perform endovascular aneurysm repair, which was thought to have low operative mortality, and that this should affect the mortality rate by reducing rupture. However, Dr Kim Hodgson, Springfield, USA, will claim that statistics and levels of evidence are not an exact science in a pragmatic world and that fitness rarely improves with time. In addition, Dr Rodney White, Los Angeles, will emphasise that the reinterventions performed after EVAR are trivial and do not contribute to mortality and that the cost argument is irrelevant. “It appears White is quite happy to recommend EVAR based on what he considers to be the state of the evidence of today, which means, presumably, that it is necessary to turn a blind eye to the EVAR 2 findings, to disregard them completely or to suspect that they are erroneous. This will be a fascinating debate,” commented Greenhalgh.

Following on from the EVAR debates, Dr Michael Lawrence-Brown, Perth, Australia, will discuss the merits of a hybrid approach of laparoscopic with endovascular techniques for aortic surgery. In the debate, “Aortic laparoscopic techniques will remain the domain of the enthusiast”, he will also emphasise that a number of surgeons have fundamental laparoscopic techniques. Speaking against the motion, Professor Ralf Kolvenbach, Dusseldorf, Germany, a great laparoscopic expert and enthusiast, will argue that an improvement in technique is required for laparoscopic aortic surgery to be applicable to a larger group of patients, which therefore limits the potential for laparoscopic aortic surgery to become a widespread practice.

The issue for the experts in the following debate is whether or not to correct an uncomplicated type B dissection using an endovascular method. The eventual answer can only be reached through long-term studies and properly randomised controlled trials. At this stage, the matter remains to some extent an open question. It is hoped that Professors Christoph Nienaber, Rostock, and Wilhelm Sandmann, Dusseldorf, Germany, will provide some much needed answers. Another important matter is the type of device used for type B dissections, compared with atherosclerotic aneurysmal disease, so the type of fixation becomes an important matter. “Perhaps this will be brought out during the debate. It is interesting to note that the discussants have interpreted this motion to mean intervention of an endovascular type so,” Greenhagh continued, “it seems that there is no discussion to be had over the use of open surgery. Perhaps that is the first conclusion.”

In the debate on Monday afternoon, “Intervention is mandatory for thoracic aortic aneurysms”, the main argument for the motion presented by Dr Edward Diethrich, Phoenix, USA, will be that thoracic aortic endografting is associated with a higher degree of success and is thought to reduce morbidity and mortality compared with what the proponents regard as the alternative, i.e. open surgery. He will emphasise that endovascular intervention avoids the need for a large incision, chest tubes, respirators and general anaesthesia, but concedes that long-term results are not yet available; although he feels that they are likely to be favourable. Mr Robert Bonser, Birmingham, UK, will argue that it is not proven whether small thoracic aneurysms do better with intervention rather than surveillance, and it has not been proved that endovascular correction is superior to surgical correction. “This could prove to be another example of practice running ahead of evidence, in favour of the endovascular repair of thoracic aortic aneurysms,” Greenhalgh added.

The advent of branched and fenestrated grafts has certainly widened the scope for interventional therapy, however whether these advances can be offered to the population at large is under debate. Arguing against the notion, “We are no closer to being able to offer branched or fenestrated systems to the population at large”, Dr Roy Greenberg, Cleveland, USA, will claim that this is essentially a matter of whether fenestrated and branched grafts are becoming more available to the average centre and they have been with us for longer than one imagines. The branched graft was achieved by Chuter et al. many years ago now, but the perception is that branched and fenestrated grafts are the domain of the minority, and the growth of this group is extremely slow. Greenhalgh asked, “Does this mean that skills need to be maintained in order to perform and correct patients in the way in which Professor Edouard Kieffer, (Paris, France, arguing for the motion) has done for 30 years, or should there be an additional effort to hasten the speed of the development of branched and fenestrated grafts?”

Much of the achievement in this area has come from the Cook Group and the advisers who have worked with the company. Cook is to be congratulated for having worked with the expertise in Malm̦, Sweden, and Perth, Australia, and putting into action the advice of these excellent groups of doctors. It would be healthy if other companies developed their own systems; or perhaps they are not prioritising this extension of the market but are instead looking for market extension in a different direction. These methods should come out in the debate.

The next debate will examine whether surgery is still the preferred option when treating femoropopliteal TASC D lesions or whether endovascular intervention has made sufficient inroads since the last meeting. At the 2005 Charing Cross Symposium, TASC D was the only domain of femoropopliteal bypass for which surgery was preferred, whereas TASC A, B and C lesions were thought to warrant management by an endovascular approach in the first instance. Interestingly, the TransAtlantic Society’s Consensus of 2000 found in favour of surgery more frequently for TASC B and C lesions.

The design of the debate, “Endovascular treatment of femoropopliteal TASC D will soon become the treatment of choice”, requires that the speakers should gaze into the future. Naturally, they do not have the evidence, so they are free to imagine where they think the subject will go. Will the endovascular revolution engulf even TASC D lesions? On the face of it, surgery will always be indicated in this situation, and we have the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL) trial now to show in randomised form what ‘angioplasty first’ and ‘surgery first’ can do, in femoropopliteal lesions, so there is more evidence accumulating all the time.

Owing to the availability of subintimal angioplasty, some believe that even TASC D lesions will become the domain of ‘angioplasty first’ within three years. No one knows, but because of the ability of several endovascular specialists there is the possibility that subintimal angioplasty and therefore endovascular techniques by at least this method could be preferred to surgery. “It will be interesting to hear how the debate goes and whether surgery for femoropopliteal disease still has its champions.” Greenhalgh enthused.Carotid debates

The carotid debates begin with the best management of asymptomatic carotid stenosis. Ms Alison Halliday, London UK, will argue that following the Asymptomatic Carotid Surgery Trial (ACST), practice has changed on both sides of the Atlantic, and she has persuasive data that compare the number of asymptomatic procedures before and after the recent trial results. Her opponent, Dr Barry Katzen, Miami, USA, feels that the comparison that Halliday is calling for, in the so-called ACST-2 trial, fails to include the best medical group.

The ACST-2 trial is due to compare carotid stent against carotid endarterectomy in asymptomatic patients and Halliday believes that it is not necessary to have another control group, as in the original ACST-1 trial. Katzen will argue that times are changing rapidly, and that best medical treatment is improving all the time, so it is absolutely vital to include an ongoing control group without intervention in order to be certain that stent and/or surgery is superior to up-to-date best medical treatment, as proposed in the Transatlantic Asymptomatic Carotid Intervention Trial (TACIT) announced at Charing Cross in 2005. TACIT will study all-risk patients, assigning them to one of three treatment arms (best medical therapy alone, best medical therapy plus carotid endarterectomy and best medical therapy plus carotid artery stenting with embolic protection).

Greenhalgh commented, “It will be interesting to see what the audience makes of the argument. However, it would be regrettable if two completely separate trials on similar lines were to go ahead, therefore halving the number of patients recruited to each. Surely it would be better in some way to pool this excellent opportunity, to have one large trial and to involve all key players in it.”

Moving on from discussing the best management for carotid stenosis, the subsequent debate will discuss the imaging modalities required and, if any, their possible effects on treatment choices. The debate, “The additional imaging required beyond duplex ultrasound before stenting is justified and not an incentive towards carotid endarterectomy”, follows on from the realisation that carotid endarterectomy has become a procedure to be performed based upon duplex ultrasound, and thereby excludes the need for a diagnostic arteriogram. In the past, the diagnostic arteriogram contributed a significant morbidity; improving duplex scanning has allowed carotid surgery to be performed without any investigative morbidity whatsoever. This leads surgeons to be inclined to include the morbidity of the investigation with the morbidity and mortality of the procedure.

Therefore, if carotid stenting requires invasive diagnostic angiography, any morbidity associated with that would be added to the procedure because the investigation is different – it is not just a matter of comparing the results of carotid stenting with those of carotid surgery. Thus, the concept of additional imaging is there for discussion, and ‘additional imaging’ is verified as ‘additional beyond duplex ultrasound’ on the assumption that duplex ultrasound is a basic requirement for all patients. “The question is whether the additional imaging is justified, which is called for when carotid stenting is considered.” added Greenhalgh

Next, Mr Michael Gough, Leeds, UK, will argue that “Eversion endarterectomy should be used selectively and not routinely”, highlighting a lack of data from randomised trials and any advantage of eversion endarterectomy over of standard carotid endarterectomy remain unproven. He will also draw attention to the fact that more than 50% of patients in trials were asymptomatic, which raises doubts about the generalisability of the results to symptomatic patients, and that a number of anatomical situations specifically discourage the use of eversion endarterectomy. However, Professor Dieter Raithel, Nuremberg, Germany, will argue for routine eversion endarterectomy based on personal experience with low morbidity and low mortality, and a low restenosis rate.

Although Raithel will acknowledge that he would exclude patients for a number of anatomical situations (hostile neck, re-do surgery, extreme coiling and small caliber), he will claim that eversion endarterectomy needs to be learned and that it should be used in certain situations. “It will be helpful for the audience to know in what circumstances it is beneficial, if it is beneficial at all, and this promises to be a very informative discussion.” Greenhalgh opined.

The last carotid debate will focus on cerebral protection. Professor Alberto Cremonesi, Cotignola, Italy, will quote level 2 evidence in favour of cerebral protection. Opposing the motion, Dr Sumaira Macdonald, Newcastle, UK, will concede that there is evidence that all protection systems are capable of catching macroemboli, however, she will note that there is no level 1 evidence that cerebral protection reduces the risk of procedural stroke. “The audience will seek to know which approach to take in their practice, and from that point of view it will be a fascinating debate,” he added.

The next debate will discuss the failure of an arterial reconstruction and to wonder which fares best: debulking with endarterectomy or bypass. Professor Frans Moll, Utrecht, the Netherlands, will argue in favour of debulking being superior when there is failure. However, Professor Cliff Shearman, Southampton, UK, will claim that bypass lasts longer than debulking, and debulking and endarterectomy fails earlier, so bypass is better, thus in a sense side-stepping the implied question of the debate. “In the end, a clinician needs to know which way to reconstruct, and it will be interesting to hear these two argue their corner.” Greenhalgh commented.

In the discussion, “No popliteal aneurysm is safe to leave”, Professor Giorgio Biasi, Milan, Italy, will claim that the very presence of a popliteal aneurysm is sinister, and the sudden catastrophe should be awaited and expected. Therefore, the level of fear has to be reduced, and how better to do this than by fixing the popliteal aneurysm. Biasi will suggest that there are not any subgroups of popliteal aneurysms or circumstances under which popliteal aneurysms should not be fixed. Popliteal aneurysm equals fear equals correction required.

Arguing against this standpoint will be Professor Nick Cheshire, London, UK, who claims that conservative management for asymptomatic, small popliteal aneurysms of less than 3cm diameter are safe, and that these aneurysms are at low risk of thrombosis. This being the case, he will argue that there is a subset of popliteal aneurysms that do not need to be fixed immediately. “It is hoped that, after this debate, the audience will be left with a clear guideline for when to intervene.” Greenhalgh said.The penultimate debate, “Endovascular popliteal aneurysm repair will become the gold standard”, is certainly a discussion the Vice-President of the United States would like to see! There is a view that endovascular treatment of popliteal aneurysm is the gold standard, however what is the evidence for this? Professors Geoffrey White, Sydney, Australia, and Matt Thompson, London, UK, will make this a very captivating debate.

Wrapping up the programme on Tuesday, Dr Jacques Bleyn, Antwerp, Belgium, will speak against the motion, “There is no evidence on the efficacy of angioplasty with or without stent for intermittent claudication”. Bleyn accepts that there is no evidence that angioplasty with or without stenting benefits intermittent claudication. Nevertheless, he will argue that evidence is not required, and that if the patient complains, the lesion should be fixed; this is therefore another area in which the specialist is encouraging practice to run ahead of evidence. He will add that society should expect to pay for improved quality of life, and that angioplastic correction of a lesion causing intermittent claudication will improve quality of life is therefore justified. Mr Jonothan Earnshaw, Gloucester, UK, will argue for the motion. It will be an interesting debate when these issues come out.

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