Is carotid artery stenting equivalent or superior to carotid endarterectomy for treatment of carotid artery stenosis
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《血管的通路杂志》
a Department of Cardiothoracic Surgery, James Cook University Hospital, Middlesbrough, UK
b Department of Interventional Radiology, Freeman Hospital, Newcastle, UK
Abstract
A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether carotid artery stenting (CAS) is equivalent or even superior to carotid endarterectomy (CEA) for the treatment of significant carotid artery stenosis. Four hundred and ninety-four papers were identified, of which 14 papers including five randomised controlled trials (RCTs) presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. We conclude that the risk of peri-procedure stroke or death was similar for patients treated with carotid artery angioplasty±stenting and those treated with surgery. However, CAS did reduce the risk of minor complications at the site of vascular access, the incidence of cranial nerve injury, and may reduce economic costs due to shorter hospital stays and earlier return to work. Long term follow-up of these patients is, however, lacking. There are currently four large multi-centre RCTs in progress and their results will determine whether CAS will surpass CEA as the gold standard in the future.
Key Words: Evidence-based medicine; Carotid-artery stenting; Carotid endarterectomy; Carotid stenosis
1. Introduction
A best evidence topic was constructed according to a structured protocol as previously described [1].
2. Clinical scenario
You are a first year radiology registrar who performs a carotid-artery duplex ultrasound on a symptomatic patient that reveals an 80% unilateral stenosis. The patient has heard about endovascular carotid angioplasty with stenting (CAS) as an alternative to carotid endarterectomy (CEA) and is keen to have a minimally invasive procedure. However, you are unsure whether there is any evidence to suggest that CAS is equivalent to the traditional gold standard of CEA.
3. Three-part question
Is [carotid-artery stenting] superior to [carotid endar- terectomy] for the treatment of patients with [significant carotid artery stenosis].
4. Search strategy
A Medline search from 1966–July 2005 using the OVID interface [exp carotid arteries/OR carotid.mp] AND [exp endarterectomy, carotid/OR endarterectomy.mp] AND [exp stents/OR stent.mp] LIMIT to Human. The reference lists of selected journals were also searched.
5. Search outcome
Four hundred and ninety-four papers were found using Medline and hand searching, from which 14 were relevant. The relevant papers included one meta-analysis, five randomised controlled trials (RCTs) and four published protocols for RCTs in progress (Table 1). The authors of each of these trials in progress were contacted via e-mail to get a progress report.
6. Results
Brown et al. performed a comprehensive meta-analysis in 2003 comparing the peri-procedure death and stroke rates after either CAS or CEA. Using strict entry criteria, they selected five RCTs (1157 patients), of which two were completed (608 patients) [2,3] and three were stopped prematurely (549 patients) [4–6]. They found no significant differences between the odds of death, any stroke or disabling stroke at either 30 days or one year post-procedure. However, due to significant heterogeneity within the data analysed, the authors were unable to suggest any changes to current clinical practice [7].
The WALLSTENT trial [5,8] was abandoned by the commercial sponsors and has only been published in abstract form. Preliminary analysis revealed a significantly higher 30-days peri-procedure complication rate (any death or stroke) for the CAS group compared to the CEA group. The weaknesses of the WALLSTENT study were that distal cerebral protection devices were not used in the CAS group, peri-procedure anti-platelet therapy was rudimentary (only aspirin was used) and the level of expertise of their interventionalist was not comparable to those performing the surgical endarterectomy. Furthermore, the stent used was not a dedicated carotid artery stent. It has subsequently been shown that the use of a dedicated carotid-stent system significantly reduces the adverse event rate when compared with stents adopted from the peripheral or coronary platforms [9].
The Leicester trial [4] was stopped by the data monitoring committee at the first interim analysis because 5/7 patients in the CAS arm of the study suffered a stroke compared to 0/10 for the CEA group. This study has several weaknesses: distal cerebral protection devices were not used, there was no prior imaging of the origin of the major head/neck vessels to exclude disease that would ordinarily constitute a contraindication to an endovascular approach, only a single anti-platelet agent was used (major endovascular units were already advocating a dual anti-platelet regime [10]), the interventionalist had limited experience whilst the surgeons had considerable expertise, a non-dedicated wallstent was used and finally pre-dilation was not routine. Pre-dilation is essential because it is not possible to pass a 7 French device (2.3 mm) through a 70% carotid artery stenosis (best residual channel of 1.8 mm) without some uncontrolled plaque disruption. Pre-dilation is used to help with passage of the unexpanded stent and is not to be confused with angioplasty of the stenosed vessel. The numbers are small but this trial does highlight the problems associated with treating a relatively unselected population.
The CAVATAS trial recruited patients from March 1992 to July 1997 and long-term follow up (more than five years) is ongoing. In 1994 carotid stents became available so the CAS group can be subdivided into two groups: a pre-1994 group which only had angioplasty (74%) and a post-1994 group that had angioplasty plus stenting at the discretion of the interventionalist. Because there was no mention of distal protection devices and the majority of the patients were not stented, the data available from this study are based on out-dated techniques and not relevant to best current clinical practice.
The Kentucky trial [3] recruited symptomatic patients with an ipsilateral stenosis of greater than 70% to either CAS (without distal cerebral protection) or CEA. At the 24-month follow up, there were no post-operative disabling strokes in this study. Follow-up was carried out within 24 h of the procedure and up until 24 months, using carotid duplex, but did not reveal any differences between the two groups with regards to carotid artery patency or recurrence of symptoms.
The SAPPHIRE trial [6] demonstrated that CAS (with a distal protection device) was not inferior to CEA with regards to the primary endpoint and in addition found that the CAS group had a significantly lower incidence of cranial nerve palsy and a reduced hospital stay compared to those in the CEA group. However, this trial has been criticised for being prematurely stopped as there was increasing reluctance amongst clinicians to recommend CEA and for the high adverse event rate in asymptomatic patients in both limbs of the trial relative to the AHA recommendations [11].
There are four ongoing multi-centre trials comparing CEA with CAS: the International Carotid Stenting Study (ICSS) [12] also known as CAVATAS-2, Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) [13], Stent-protected Percutaneous Angioplasty of the Carotid vs. Endarterectomy (SPACE) [14] and Endarterectomy vs. Angioplasty in patients with Severe Symptomatic Stenosis (EVA-3S) [15] (Table 2). The results of the European trials (SPACE, ICSS and EVA-3S) will be pooled.
7. Clinical bottom line
The risk of peri-procedure stroke or death was similar for patients treated with carotid artery angioplasty±stenting and those treated with surgery. However, CAS did reduce the risk of minor complications at the site of vascular access, the incidence of cranial nerve injury and may reduce economic costs due to shorter hospital stays and earlier return to work. Long term follow-up of these patients is, however, lacking. There are currently four large multi-centre RCTs in progress and their results will determine whether CAS will surpass CEA as the gold standard.
References
Dunning J, Prendergast B, Mackway-Jones K. Towards evidence based medicine in cardiothoracic surgery: best BETS. Interact CardioVasc Thorac Surg 2003;2:405–409.
Anonymous. Endovascular vs. surgical treatment in patients with carotid stenosis in the carotid and vertebral artery transluminal angioplasty study (CAVATAS): a randomised trial. Lancet 2001;357:1729–1737.
Brooks WH, McClure RR, Jones MR, Coleman TC, Breathitt L. Carotid angioplasty and stenting versus carotid endarterectomy: randomized trial in a community hospital. J Am Coll Cardiol 2001;38:1589–1595.
Naylor AR, Bolia A, Abbott RJ, Pye IF, Smith J, Lennard N, Lloyd AJ, London NJ, Bell PR. Randomized study of carotid angioplasty and stenting versus carotid endarterectomy: a stopped trial. J Vasc Surg 1998;28:326–334.
The Wallstent Study, Personal communication, 2001.
Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, Bajwa TK, Whitlow P, Strickman NE, Jaff MR, Popma JJ, Snead DB, Cutlip DE, Firth BG, Ouriel K. Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med 2004;351:1493–1501.
Coward LJ, Featherstone RL, Brown MM. Percutaneous transluminal angioplasty and stenting for carotid artery stenosis. The Cochrane Database of Systematic Reviews 2004;.
Alberts MJ. Results of a multicentre prospective randomised trial of carotid artery stenting versus carotid endarterectomy. Stroke 2001;32:325.
McKevitt FM, Macdonald S, Venables GS, Cleveland TJ, Gaines PA. Complications following carotid angioplasty and carotid stenting in patients with symptomatic carotid artery disease. Cerebrovasc Dis 2004;17:28–34.
Yadav JS, Roubin GS, King P, Iyer S, Vitek J. Angioplasty and stenting for restenosis after carotid endarterectomy. Initial experience. Stroke 1996;27:2075–2079.
Moore WS, Barnett HJ, Beebe HG, Bernstein EF, Brener BJ, Brott T, Caplan LR, Day A, Goldstone J, Hobson 2nd RW. Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the Ad Hoc Committee, American Heart Association. Circulation 1995;91:566–579.
Featherstone RL, Brown MM, Coward LJ. International carotid stenting study: protocol for a randomised clinical trial comparing carotid stenting with endarterectomy in symptomatic carotid artery stenosis. Cerebrovasc Dis 2004;18:69–74.
Hobson 2nd RW, Howard VJ, Roubin GS, Brott TG, Ferguson RD, Popma JJ, Graham DL, Howard G. Carotid artery stenting is associated with increased complications in octogenarians: 30-day stroke and death rates in the CREST lead-in phase. J Vasc Surg 2004;40:1106–1111.
Ringleb PA, Kunze A, Allenberg JR, Hennerici MG, Jansen O, Maurer PC, Zeumer H, Hacke W. The Stent-Supported Percutaneous Angioplasty of the Carotid Artery vs. Endarterectomy Trial. Cerebrovasc Dis 2004;18:66–68.
Mas JL, Chatellier G, Beyssen B. EVA-3S Investigators. Carotid angioplasty and stenting with and without cerebral protection: clinical alert from the Endarterectomy vs. Angioplasty in Patients With Symptomatic Severe Carotid Stenosis (EVA-3S) trial. Stroke 2004;35:e18–20.(Vivek Shrivastava, Siucha)
b Department of Interventional Radiology, Freeman Hospital, Newcastle, UK
Abstract
A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether carotid artery stenting (CAS) is equivalent or even superior to carotid endarterectomy (CEA) for the treatment of significant carotid artery stenosis. Four hundred and ninety-four papers were identified, of which 14 papers including five randomised controlled trials (RCTs) presented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. We conclude that the risk of peri-procedure stroke or death was similar for patients treated with carotid artery angioplasty±stenting and those treated with surgery. However, CAS did reduce the risk of minor complications at the site of vascular access, the incidence of cranial nerve injury, and may reduce economic costs due to shorter hospital stays and earlier return to work. Long term follow-up of these patients is, however, lacking. There are currently four large multi-centre RCTs in progress and their results will determine whether CAS will surpass CEA as the gold standard in the future.
Key Words: Evidence-based medicine; Carotid-artery stenting; Carotid endarterectomy; Carotid stenosis
1. Introduction
A best evidence topic was constructed according to a structured protocol as previously described [1].
2. Clinical scenario
You are a first year radiology registrar who performs a carotid-artery duplex ultrasound on a symptomatic patient that reveals an 80% unilateral stenosis. The patient has heard about endovascular carotid angioplasty with stenting (CAS) as an alternative to carotid endarterectomy (CEA) and is keen to have a minimally invasive procedure. However, you are unsure whether there is any evidence to suggest that CAS is equivalent to the traditional gold standard of CEA.
3. Three-part question
Is [carotid-artery stenting] superior to [carotid endar- terectomy] for the treatment of patients with [significant carotid artery stenosis].
4. Search strategy
A Medline search from 1966–July 2005 using the OVID interface [exp carotid arteries/OR carotid.mp] AND [exp endarterectomy, carotid/OR endarterectomy.mp] AND [exp stents/OR stent.mp] LIMIT to Human. The reference lists of selected journals were also searched.
5. Search outcome
Four hundred and ninety-four papers were found using Medline and hand searching, from which 14 were relevant. The relevant papers included one meta-analysis, five randomised controlled trials (RCTs) and four published protocols for RCTs in progress (Table 1). The authors of each of these trials in progress were contacted via e-mail to get a progress report.
6. Results
Brown et al. performed a comprehensive meta-analysis in 2003 comparing the peri-procedure death and stroke rates after either CAS or CEA. Using strict entry criteria, they selected five RCTs (1157 patients), of which two were completed (608 patients) [2,3] and three were stopped prematurely (549 patients) [4–6]. They found no significant differences between the odds of death, any stroke or disabling stroke at either 30 days or one year post-procedure. However, due to significant heterogeneity within the data analysed, the authors were unable to suggest any changes to current clinical practice [7].
The WALLSTENT trial [5,8] was abandoned by the commercial sponsors and has only been published in abstract form. Preliminary analysis revealed a significantly higher 30-days peri-procedure complication rate (any death or stroke) for the CAS group compared to the CEA group. The weaknesses of the WALLSTENT study were that distal cerebral protection devices were not used in the CAS group, peri-procedure anti-platelet therapy was rudimentary (only aspirin was used) and the level of expertise of their interventionalist was not comparable to those performing the surgical endarterectomy. Furthermore, the stent used was not a dedicated carotid artery stent. It has subsequently been shown that the use of a dedicated carotid-stent system significantly reduces the adverse event rate when compared with stents adopted from the peripheral or coronary platforms [9].
The Leicester trial [4] was stopped by the data monitoring committee at the first interim analysis because 5/7 patients in the CAS arm of the study suffered a stroke compared to 0/10 for the CEA group. This study has several weaknesses: distal cerebral protection devices were not used, there was no prior imaging of the origin of the major head/neck vessels to exclude disease that would ordinarily constitute a contraindication to an endovascular approach, only a single anti-platelet agent was used (major endovascular units were already advocating a dual anti-platelet regime [10]), the interventionalist had limited experience whilst the surgeons had considerable expertise, a non-dedicated wallstent was used and finally pre-dilation was not routine. Pre-dilation is essential because it is not possible to pass a 7 French device (2.3 mm) through a 70% carotid artery stenosis (best residual channel of 1.8 mm) without some uncontrolled plaque disruption. Pre-dilation is used to help with passage of the unexpanded stent and is not to be confused with angioplasty of the stenosed vessel. The numbers are small but this trial does highlight the problems associated with treating a relatively unselected population.
The CAVATAS trial recruited patients from March 1992 to July 1997 and long-term follow up (more than five years) is ongoing. In 1994 carotid stents became available so the CAS group can be subdivided into two groups: a pre-1994 group which only had angioplasty (74%) and a post-1994 group that had angioplasty plus stenting at the discretion of the interventionalist. Because there was no mention of distal protection devices and the majority of the patients were not stented, the data available from this study are based on out-dated techniques and not relevant to best current clinical practice.
The Kentucky trial [3] recruited symptomatic patients with an ipsilateral stenosis of greater than 70% to either CAS (without distal cerebral protection) or CEA. At the 24-month follow up, there were no post-operative disabling strokes in this study. Follow-up was carried out within 24 h of the procedure and up until 24 months, using carotid duplex, but did not reveal any differences between the two groups with regards to carotid artery patency or recurrence of symptoms.
The SAPPHIRE trial [6] demonstrated that CAS (with a distal protection device) was not inferior to CEA with regards to the primary endpoint and in addition found that the CAS group had a significantly lower incidence of cranial nerve palsy and a reduced hospital stay compared to those in the CEA group. However, this trial has been criticised for being prematurely stopped as there was increasing reluctance amongst clinicians to recommend CEA and for the high adverse event rate in asymptomatic patients in both limbs of the trial relative to the AHA recommendations [11].
There are four ongoing multi-centre trials comparing CEA with CAS: the International Carotid Stenting Study (ICSS) [12] also known as CAVATAS-2, Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) [13], Stent-protected Percutaneous Angioplasty of the Carotid vs. Endarterectomy (SPACE) [14] and Endarterectomy vs. Angioplasty in patients with Severe Symptomatic Stenosis (EVA-3S) [15] (Table 2). The results of the European trials (SPACE, ICSS and EVA-3S) will be pooled.
7. Clinical bottom line
The risk of peri-procedure stroke or death was similar for patients treated with carotid artery angioplasty±stenting and those treated with surgery. However, CAS did reduce the risk of minor complications at the site of vascular access, the incidence of cranial nerve injury and may reduce economic costs due to shorter hospital stays and earlier return to work. Long term follow-up of these patients is, however, lacking. There are currently four large multi-centre RCTs in progress and their results will determine whether CAS will surpass CEA as the gold standard.
References
Dunning J, Prendergast B, Mackway-Jones K. Towards evidence based medicine in cardiothoracic surgery: best BETS. Interact CardioVasc Thorac Surg 2003;2:405–409.
Anonymous. Endovascular vs. surgical treatment in patients with carotid stenosis in the carotid and vertebral artery transluminal angioplasty study (CAVATAS): a randomised trial. Lancet 2001;357:1729–1737.
Brooks WH, McClure RR, Jones MR, Coleman TC, Breathitt L. Carotid angioplasty and stenting versus carotid endarterectomy: randomized trial in a community hospital. J Am Coll Cardiol 2001;38:1589–1595.
Naylor AR, Bolia A, Abbott RJ, Pye IF, Smith J, Lennard N, Lloyd AJ, London NJ, Bell PR. Randomized study of carotid angioplasty and stenting versus carotid endarterectomy: a stopped trial. J Vasc Surg 1998;28:326–334.
The Wallstent Study, Personal communication, 2001.
Yadav JS, Wholey MH, Kuntz RE, Fayad P, Katzen BT, Mishkel GJ, Bajwa TK, Whitlow P, Strickman NE, Jaff MR, Popma JJ, Snead DB, Cutlip DE, Firth BG, Ouriel K. Protected carotid-artery stenting versus endarterectomy in high-risk patients. N Engl J Med 2004;351:1493–1501.
Coward LJ, Featherstone RL, Brown MM. Percutaneous transluminal angioplasty and stenting for carotid artery stenosis. The Cochrane Database of Systematic Reviews 2004;.
Alberts MJ. Results of a multicentre prospective randomised trial of carotid artery stenting versus carotid endarterectomy. Stroke 2001;32:325.
McKevitt FM, Macdonald S, Venables GS, Cleveland TJ, Gaines PA. Complications following carotid angioplasty and carotid stenting in patients with symptomatic carotid artery disease. Cerebrovasc Dis 2004;17:28–34.
Yadav JS, Roubin GS, King P, Iyer S, Vitek J. Angioplasty and stenting for restenosis after carotid endarterectomy. Initial experience. Stroke 1996;27:2075–2079.
Moore WS, Barnett HJ, Beebe HG, Bernstein EF, Brener BJ, Brott T, Caplan LR, Day A, Goldstone J, Hobson 2nd RW. Guidelines for carotid endarterectomy. A multidisciplinary consensus statement from the Ad Hoc Committee, American Heart Association. Circulation 1995;91:566–579.
Featherstone RL, Brown MM, Coward LJ. International carotid stenting study: protocol for a randomised clinical trial comparing carotid stenting with endarterectomy in symptomatic carotid artery stenosis. Cerebrovasc Dis 2004;18:69–74.
Hobson 2nd RW, Howard VJ, Roubin GS, Brott TG, Ferguson RD, Popma JJ, Graham DL, Howard G. Carotid artery stenting is associated with increased complications in octogenarians: 30-day stroke and death rates in the CREST lead-in phase. J Vasc Surg 2004;40:1106–1111.
Ringleb PA, Kunze A, Allenberg JR, Hennerici MG, Jansen O, Maurer PC, Zeumer H, Hacke W. The Stent-Supported Percutaneous Angioplasty of the Carotid Artery vs. Endarterectomy Trial. Cerebrovasc Dis 2004;18:66–68.
Mas JL, Chatellier G, Beyssen B. EVA-3S Investigators. Carotid angioplasty and stenting with and without cerebral protection: clinical alert from the Endarterectomy vs. Angioplasty in Patients With Symptomatic Severe Carotid Stenosis (EVA-3S) trial. Stroke 2004;35:e18–20.(Vivek Shrivastava, Siucha)