Perspectives Commentary on: Proximal versus Distal Protection During Carotid Artery Stenting: Analysis of the Two Treatment Approaches and Associated Clinical Outcomes by Mokin World Neurosurg 81:543-548, 2014
William J. Mack, M.D. Assistant Professor of Neurological Surgery Department of Neurological Surgery University of Southern California Keck School of Medicine
Plaque Morphology and Embolic Protection Strategies in Carotid Artery Stenting Matthew S. Tenser and William J. Mack
E
ach year, approximately 800,000 strokes occur in the United States, 80% of which are ischemic. Of that 80%, 15%e20% are caused by extracranial carotid artery disease (3). The risk of stroke due to both symptomatic and asymptomatic carotid stenosis, as well as the benefit of repair by carotid endarterectomy (CEA) or carotid angioplasty and stenting (CAS), has been well documented in clinical trials. Both the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (ECST) demonstrated a significant benefit to CEA for those with severe (70%e80%) symptomatic stenosis. In NASCET, the risk of stroke with medical therapy was 26% over 2 years compared to 9% with CEA (16). The ECST documented stroke risks over 3 years for medical therapy and CEA to be 26.5% and 14.9%, respectively (6, 7). CEA has also been shown to be of benefit in those with asymptomatic disease, although the effect was not as profound. The Asymptomatic Carotid Atherosclerosis Study (ACAS) reported an 11% risk of stroke over 5 years with medical therapy versus 5.1% with CEA for those with greater than 60% stenosis (8), and the Asymptomatic Carotid Surgery Trial (ACST) demonstrated an 11.8% risk with medical
Key words Adverse events - Carotid stenting - Distal protection - Embolic protection - Proximal protection - Treatment outcome -
Abbreviations and Acronyms ACAS: Asymptomatic Carotid Atherosclerosis Study ACST: Asymptomatic Carotid Surgery Trial CAS: Carotid angioplasty and stenting CEA: Carotid endarterectomy CREST: Carotid Revascularization Endarterectomy vs. Stenting Trial ECST: European Carotid Surgery Trial NASCET: North American Symptomatic Carotid Endarterectomy Trial TIA: Transient ischemic attack
WORLD NEUROSURGERY - [-]: ---, MONTH 2014
therapy versus 6.4% with CEA for patients with greater than 70% stenosis (14). The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) is a randomized study of CAS and CEA in both symptomatic and asymptomatic patients. Eligible patients had a stenosis of 50% or greater on catheter angiography, 70% or greater on ultrasound, or 70% or greater on computed tomographic angiography or magnetic resonance angiography if the stenosis was 50%e69% on ultrasound as well. They found no significant difference in the 4-year rate of stroke or death for CAS compared with CEA (6.4% and 4.7%, respectively) (4). Although physicians who treat stroke and cerebrovascular disease would agree that the majority of symptomatic carotid lesions (stroke, transient ischemic attack [TIA]) should be treated, the ideal treatment modality is based on many factors and varies from patient to patient. CAS has been approved as an alternative to CEA for patients with stenosis greater than 70% on noninvasive imaging or greater than 50% on catheter angiography, assuming a perioperative risk of
William J. Mack, M.D. Assistant Professor of Neurological Surgery Department of Neurological Surgery University of Southern California Keck School of Medicine
Plaque Morphology and Embolic Protection Strategies in Carotid Artery Stenting Matthew S. Tenser and William J. Mack
E
ach year, approximately 800,000 strokes occur in the United States, 80% of which are ischemic. Of that 80%, 15%e20% are caused by extracranial carotid artery disease (3). The risk of stroke due to both symptomatic and asymptomatic carotid stenosis, as well as the benefit of repair by carotid endarterectomy (CEA) or carotid angioplasty and stenting (CAS), has been well documented in clinical trials. Both the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (ECST) demonstrated a significant benefit to CEA for those with severe (70%e80%) symptomatic stenosis. In NASCET, the risk of stroke with medical therapy was 26% over 2 years compared to 9% with CEA (16). The ECST documented stroke risks over 3 years for medical therapy and CEA to be 26.5% and 14.9%, respectively (6, 7). CEA has also been shown to be of benefit in those with asymptomatic disease, although the effect was not as profound. The Asymptomatic Carotid Atherosclerosis Study (ACAS) reported an 11% risk of stroke over 5 years with medical therapy versus 5.1% with CEA for those with greater than 60% stenosis (8), and the Asymptomatic Carotid Surgery Trial (ACST) demonstrated an 11.8% risk with medical
Key words Adverse events - Carotid stenting - Distal protection - Embolic protection - Proximal protection - Treatment outcome -
Abbreviations and Acronyms ACAS: Asymptomatic Carotid Atherosclerosis Study ACST: Asymptomatic Carotid Surgery Trial CAS: Carotid angioplasty and stenting CEA: Carotid endarterectomy CREST: Carotid Revascularization Endarterectomy vs. Stenting Trial ECST: European Carotid Surgery Trial NASCET: North American Symptomatic Carotid Endarterectomy Trial TIA: Transient ischemic attack
WORLD NEUROSURGERY - [-]: ---, MONTH 2014
therapy versus 6.4% with CEA for patients with greater than 70% stenosis (14). The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) is a randomized study of CAS and CEA in both symptomatic and asymptomatic patients. Eligible patients had a stenosis of 50% or greater on catheter angiography, 70% or greater on ultrasound, or 70% or greater on computed tomographic angiography or magnetic resonance angiography if the stenosis was 50%e69% on ultrasound as well. They found no significant difference in the 4-year rate of stroke or death for CAS compared with CEA (6.4% and 4.7%, respectively) (4). Although physicians who treat stroke and cerebrovascular disease would agree that the majority of symptomatic carotid lesions (stroke, transient ischemic attack [TIA]) should be treated, the ideal treatment modality is based on many factors and varies from patient to patient. CAS has been approved as an alternative to CEA for patients with stenosis greater than 70% on noninvasive imaging or greater than 50% on catheter angiography, assuming a perioperative risk of
