At the Multidisciplinary European Endovascular Therapy (MEET) meeting 2003 held in Marseilles, France, a day each was dedicated to the carotid artery and the thoracic aorta.

During the controversies session on the carotid day, Roger Greenhalgh told the audience that carotid stenting has no role in asymptomatic patients with carotid stenosis over 80%. He explained: “The natural history suggests a 1% stroke rate per year for asymptomatic carotid stenoses of <70% and 3% per year for patients with stenoses >70%. Therefore for patients with 80% stenosis, the expected stroke rate per year from no intervention will be in the region of 3% to 3.5% per year. I am not aware that reliable clinical data has confirmed this but this would be the expectation.”

He continued: “There are no multi-centre studies of a large population treatments of carotid stenting in such patients showing that the morbidity rate is under 3%. The stroke rate would have to be extremely low for carotid stenting for it to improve a stroke risk of 3% per year. Consequently, until carotid stenting can be performed with a minimal stroke risk, it should not be performed in asymptomatic patients. This comprehensive review of the current situation left little room for debate with Klaus Mathias, the scheduled opposition, agreeing with Greenhalgh’s conclusions.

Greenhalgh later looked at the role carotid stenting had in patients at high risk of stroke, i.e. those who are symptomatic and that have severe stenosis. He pointed to the fact that good level 1 evidence exists for carotid endarterectomy for symptomatic stenosis >70% (NASCET, ECST), proving its efficacy. However, similarly thorough evidence is absent for carotid stenting.

The Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) and ACCULINK for Revascularisation of Carotids in High-Risk Patients (ARCHeR) are both looking at stenting in patients at high surgical risk.

In SAPPHIRE, at 30-day follow up, the major adverse event (defined as death, stroke or myocardial infarction) rate for the randomised stented group was 5.8% versus 12.6% for the endarterectomy-treated patients.

In patients enrolled in ARCHeR, the 30-day total major adverse event (MAE) rate – defined as all-cause stroke, death and myocardial infarction was 7.8%.

Greenhalgh asked: “What is the definition of high risk? At the moment, several different types of endpoints are being used to try and show that one technique is better than another. Surely, the aim should be to prevent strokes. Data from the trials so far demonstrates that the natural history beats treatment results. The patients would have been better off having no intervention whatsoever.” This begs the question, why compare treatments when no intervention appears to be the best option?

Greenhalgh pointed out that approximately 92,000 carotid endarterectomies are performed in Europe each year, opposed to approximately 8,000 carotid stenting procedures, according to the European Vascular and Endovascular Monitor (EVEM). “It is likely that the high-risk patients are operated on,” said Greenhalgh. “This is hardly surprising,” he continued, “because it is known that an intervention is required and for the intervention to be switched to carotid stenting, first the onus is upon carotid stenting to be demonstrated to be as good as carotid surgery.”

“Coronary artery stenting has been considered to have potential advantages compared to surgery, but in practice we need data from a scientifically rigorous study to prove the better treatment option,” said Bernard Beyssen of the Hospital Européen Georges Pompidou, Paris, France. “In France, CAS is still not reimbursed and not authorised as routine for atheromatous lesions (except in trials with ethical committee approval) and therefore remains a non-reimbursable procedure. In consequence, the decision to start a multicentre prospective randomised study (EVA-3S) was made.”

EVA-3S (Endarterectomy Versus Angioplasty in patients with Severe Symptomatic carotid Stenosis) is a large, multicentre, Prospective, Randomised Open Blinded Endpoint (PROBE) Study which aims to assess the safety and long-term benefit of carotid angioplasty with stenting compared to carotid surgery in patients with recently symptomatic, severe (>= 70%, according to NASCET criteria) atherosclerotic carotid stenosis suitable for both angioplasty with stenting and carotid endarterectomy

Since the trial began in October 2000, 26 centres have enrolled more than 200 patients, though enrolment of up to 900 is planned. The primary endpoints of this trial are any stroke or death within 30 days of the procedure, or any stroke or death within 30 days of the procedure plus ipsilateral stroke during the follow-up period (two to four years).

Ted Diethrich of the Arizona Heart Institute then discussed the Carotid Revasularization Endarterectomy versus Stent Trial (CREST) and the Carotid Revascularization with Endarterectomy and Stenting Systems (CARESS) registry. CARESS is an observational cohort trial that will study both symptomatic and asymptomatic patients excluded from CREST. CARESS is designed to compare the effectiveness of carotid stenting and cerebral protection with endarterectomy in contemporaneous controls.

Phase I enrolment was completed in December 2002 and the pivotal study of approximately 2,500 patients is expected to begin in 2003.

During the thoracic aortic day, ‘Branched and fenestrated stent grafts will never replace surgery’ was debated by Marc van Sambeek of Erasmus University Medical Centre, Rotterdam, who supported the motion, and John Reidy of Guy’s and St Thomas’ Hospital, London.

Stent grafts in the thoracic aorta were first employed in 1994 and since then their use has been largely confined to selected cases in the descending thoracic aorta. Reidy pointed out that in abdominal aortic aneurysms there is current interest in fenestrated stent grafts to enable devices to be placed when the aneurysm extends to involve the visceral arteries. “Though these devices show promise,” said Reidy, “the further step of branched devices will probably be more enduring.” However, the abdominal aorta has two great advantages over the thoracic aorta, it is relatively straight and the carotid circulation is much less tolerant of the sort of manipulations necessary for these procedures. He concluded by saying: “There is no doubt that endovascular devices for the thoracic aorta will improve but the future is best in their combined use with adjunctive surgical procedures.”

Van Sambeek pointed out the drawbacks of branched stent grafts included an enhanced risk of cerebral and distal embolization, persistent endoleaks, acute stent thrombosis, side-branch occlusion and twisting of the stent grafts. His opinion was that the currently available fenestrated and branched stent grafts will not replace conventional open surgery.