Following on form the furor that surrounded the results of the Symptomatic Severe Carotid Stenosis (EVA-3S) and the Stent-Supported Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy (SPACE) trial, there was no let up in the carotid stenting vs. surgery debate at the VEITHsymposium as Sir Peter Bell, Leicester, UK, and Jay Yadav came head to head.
Yadav began by stating that stenting trials such as the Stenting Angioplasty Protection Patients High Risk Endarterectomy (SAPPHIRE) continue to suggest that these trials offer enough scientific proof to show that carotid stenting should be offered to all high-risk patients to prevent a stroke. He cited data from the SAPPHIRE study that showed stenting had a lower percentage of target lesion revascularisation rate at 180 days (3%) than surgery (7.1%).
However Bell, a longtime critic of the SAPPHIRE study, commented, “Attempts to show that CAS is equivalent or better than carotid endarterectomy have repeatedly failed. The only trial, which has shown a benefit for stenting, is the SAPPHIRE trial which is deeply flawed and has now largely been discredited,” adding that the trial used the wrong endpoints with involvement of industry in the design of the trial.
He said that more than 400 patients were not considered for randomization for reasons, which have never been made clear. Bell continued to say that the experience of the surgeons carrying out the surgery in this trial remains in doubt and the stroke rate for both treatments in largely asymptomatic patients is higher even than the historical levels suggested 20 years ago. Bell said, “For such patients the risk of stroke is less than 2% per annum, and in the SAPPHIRE trial the rate of 5.8% at 30 days is unacceptable.”
Bell said, “Basically what this means is that the so-called experts in angioplasty involved in this trial caused more strokes in their patients than doing nothing at all. This can only mean that when the procedure is used more widely by less experienced operators the stroke rate will increase to a level which is completely unacceptable.”
He went on to say that the Carotid Acculink/Accunet Post Approval Trial to Uncover Rare Events (CAPTURE) trial is not a trial but a registry again sponsored by industry, which clearly shows no benefit from CAS in patients with carotid artery stenosis. Most of the patients in this registry (90%) were again asymptomatic and had a stroke and death rate of 4.9%.
“As far as symptomatic patients are concerned, two recent trials, the EVA 3S and SPACE trials have shown no benefit for CAS in patients with symptoms who need treatment. The EVAS/3S trial showed a big difference between surgery and stenting with a stroke and death rate of 3.9% and 9.6%, respectively. The German SPACE trial showed a stroke and death rate of 6.84% for stenting and 6.34% for surgery. The CAPTURE data for symptomatic patients had a stroke and death rate of 14% for these patients. If all these data are put together, it shows a very clear superiority for surgery and provides no evidence that CAS should be expanded and used more widely.
Bell concluded, “On the contrary, these trials show that the procedure is dangerous even in the hands of experts and should not be used more widely otherwise, a potential disaster will occur.”
Is asymptomatic stenting justified?
However, Frank Criado, director of the Center for Vascular Intervention, and chief of the Division of Vascular Surgery at Union Memorial Hospital, Baltimore, MD, asked whether intervention was ever justified for asymptomatic patients regardless of carotid severity or can stenting be justified in some cases (instead of surgery).
He said that in the US at least, carotid stenting is routinely performed for critical asymptomatic stenosis. But the reality is that there is as yet no evidence in support for stenting for non-high risk patients whether asymptomatic or asymptomatic as evidenced by severely restricted reimbursement for asymptomatic indications.
However, Criado acknowledged that stenting was probably reasonable for some asymptomatic patients, especially those at anatomical high-risk for surgery, but it most only be achieved with low-morbidity and exclude patients with a bad anatam y and unfavourable lesions.
He cited a paper from the Journal of Vascular Surgery (2006: 43; 953-8), that stated “Stenting for asymptomatic carotid stenosis has demonstrated equivalent outcomes compared with surgery despite stenting being reserved for use in a disadvantaged subset of high-risk patients owing to anatomic risk factors or medical comorbidities. These results suggest stenting should be considered reasonable treatment option in the high-risk but asymptomatic patient. Enthusiasm for stenting should be tempered by the recognition that long-term outcomes in stenting-treated asymptomatic patients remain unknown.”
Criado then assessed the future of stenting claiming that it will perhaps not be as big or as dominating as envisioned a few years ago – but it will still play a significant part in the treating carotid stenosis. Moreover, he added that stenting will be competitive in the hands of skilled/experienced operators who learn to select favourable cases and exclude less favourable ones. Such cases include angulated carotids, unfavourable lesions, unfavourable aortic arch and patients over 80-years of age. The future will lie in stratifying patients/lesions by stroke potential and need for intervention, thereby defining low risk for stenting (anatomy, lesion type/nature).
Finally, Alison Halliday, St Georges Hospital, London, UK, said that the patient was biased toward stenting because of a reduced hospital stay, no scar and the common misconception that all stents are as successful as coronary stents. In addition, she commented that physicians themselves maybe biased as they may favour one procedure and/or profit financially from carrying out the procedure. Moreover, they may believe that one procedure is superior – patients trust physicians but sometime only if the doctor knows the answer. “However, although bias exists, physicians recommending a procedure may still do so ethically because they are ‘sensitive to the needs and concerns’ of patints – but is it justified?” she added.
To conclude, Halliday said that it is ethical to perform carotid stenting or surgery in asymptomatic patients who are aware of the potential risks and benefits, but, there is no evidence that stenting is as good as, or better than surgery for treatment of asymptomatic carotid arty stenosis. Therefore she said trials such as the Asymptomatic Carotid Surgery Trial-2 are needed to determine risks and benefits.