Extracranial internal carotid artery stenosis accounts for 15% to 20% of ischemic strokes. Carotid endarterectomy (CEA) is the most common treatment for large internal carotid artery stenosis (Table 2). Early studies showed that CEA carried a high risk if performed within a few days after a large ischemic stroke (Bruteman, 1963; Blaisdell, 1969; Rob, 1969); therefore, many surgeons delayed performing CEA for four to six weeks after any stroke.
To determine the effect of delaying CEA on oper with a trend toward benefit at two years, but not associated with a clear long-term benefit. Patients who underwent surgery within two weeks of their last TIA or mild stroke derive greater benefit from CEA. Symptomatic and asymptomatic patients undergoing CEA should be given aspirin (81 or 325 mg/d) prior to surgery and for at least three months following surgery to reduce the risk of stroke, MI, and death. Although data are not available, it is recommended that aspirin (81 or 325 mg/d) be continued indefinitely provided that contraindications are absent. At this time, the available data are insufficient to declare either CEA before or simultaneous with CABG as superior in patients with concomitant carotid and coronary artery occlusive disease. For patients with severe stenosis and a recent TIA or nondisabling stroke, CEA should be performed without delay, preferably within two weeks of the patient's last symptomatic event. There is insufficient evidence to support or refute the performance of CEA within four to six weeks of a recent moderate-to-severe stroke.
Extracranial internal carotid artery stenosis accounts for 15% to 20% of ischemic strokes. Carotid endarterectomy (CEA) is the most common treatment for large internal carotid artery stenosis (Table 2). Early studies showed that CEA carried a high risk if performed within a few days after a large ischemic stroke (Bruteman, 1963; Blaisdell, 1969; Rob, 1969); therefore, many surgeons delayed performing CEA for four to six weeks after any stroke.
To determine the effect of delaying CEA on operative risk and benefit, data were pooled from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (Bond, 2003). A previous analysis of data from NASCET suggested that operative risk was not increased in patients who underwent surgery within 30 days of a nondisabling stroke (Gasecki, 1994). The retrospective subgroup analysis involved 100 surgical patients with severe (70% to 99%), angiographically defined carotid artery stenosis in whom a nondisabling hemispheric stroke was diagnosed at entry into the trial (Bond, 2003). A total of 42 CEAs were performed within 30 days (early group, ranging three to 30 days), and 58 were performed beyond 30 days (delayed group, range 33 to 117 days) after stroke. The risk of subsequent stroke after CEA was compared between the two groups. The postoperative (30 days after CEA) stroke rate was 4.8% in the early group and 5.2% in the delayed group, yielding a relative rate of 0.92 (95% CI, 0.16-5.27; P = 1.00). At the end of 18 months, the rates of any stroke or death were 11.9% and 10.3% for the early and delayed groups, respectively, resulting in a relative rate of 1.15 (95% CI, 0.38-3.52; P = 1.00). However, in the delayed group, more lesions were identified ipsilateral to the symptomatic side on the preoperative computed tomography (CT) scans.
The NASCET analysis revealed that CEA can be performed safely within two weeks of nondisabling ischemic stroke. Delaying the procedure by 30 days for patients with symptomatic high-grade stenosis exposes them to a risk of recurrent stroke, which may be avoidable by earlier surgery. The results also showed that benefit from CEA declines rapidly with increasing delay. This dx weeks after any stroke.
To determine the effect of delaying CEA on operative risk and benefit, data were pooled from the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the European Carotid Surgery Trial (Bond, 2003). A previous analysis of data from NASCET suggested that operative risk was not increased in patients who underwent surgery within 30 days of a nondisabling stroke (Gasecki, 1994). The retrospective subgroup analysis involved 100 surgical patients with severe (70% to 99%), angiographically defined carotid artery stenosis in whom a nondisabling hemispheric stroke was diagnosed at entry into the trial (Bond, 2003). A total of 42 CEAs were performed within 30 days (early group, ranging three to 30 days), and 58 were performed beyond 30 days (delayed group, range 33 to 117 days) after stroke. The risk of subsequent stroke after CEA was compared between the two groups. The postoperative (30 days after CEA) stroke rate was 4.8% in the early group and 5.2% in the delayed group, yielding a relative rate of 0.92 (95% CI, 0.16-5.27; P = 1.00). At the end of 18 months, the rates of any stroke or death were 11.9% and 10.3% for the early and delayed groups, respectively, resulting in a relative rate of 1.15 (95% CI, 0.38-3.52; P = 1.00). However, in the delayed group, more lesions were identified ipsilateral to the symptomatic side on the preoperative computed tomography (CT) scans.
The NASCET analysis revealed that CEA can be performed safely within two weeks of nondisabling ischemic stroke. Delaying the procedure by 30 days for patients with symptomatic high-grade stenosis exposes them to a risk of recurrent stroke, which may be avoidable by earlier surgery. The results also showed that benefit from CEA declines rapidly with increasing delay. This decline in benefit over time was later shown to be more pronounced in women than men (P<0.001)(Rothwell, 2004). Benefit in women was confined to those randomized to less than two weeks after their last event, irrespective of severity of stenosis.
With the number of CEA procedures increasing, appropriate qualifying schemes (ie, preoperative condition assessment), as well as optimal methods for monitoring patients peri- and postoperatively are needed. A recent, evidence-based review reported by the Therapeutics and Technology Assessment Subcommittee of the American Academy of Neurology provided the following recommendations (Chaturvedi, 2005):
- CEA is established as effective for recently symptomatic (within the previous six months) patients with 70% to 99% internal carotid artery angiographic stenosis. CEA should not be considered for symptomatic patients with <50% stenosis. CEA may be considered for patients with 50% to 69% symptomatic stenosis, but the clinician should consider additional clinical and angiographic variables. It is recommended that the patient have at least a five-year life expectancy and that the perioperative stroke/death rate should be <6% for symptomatic patients. Medical management is preferred to CEA for symptomatic patients with <50% stenosis.
- It is reasonable to consider CEA for patients between the ages of 40 and 75 years with asymptomatic stenosis of 60% to 99% if the patient has an expected five-year life expectancy and if the surgical stroke or death frequency can be reliably documented at <3%.
- No recommendation can be provided regarding the value of emergent CEA in patients with a progressing neurologic deficit.
- Clinicians should consider patient variables in CEA decision-making. Women with 50% to 69% symptomatic stenosis did not show clear benefit in previous trials. In addition, patients with hemispheric TIA/stroke had greater benefit from CEA than patients with retinal ischemic events. Clinicians should also evaluate several radiologic factors when considering CEA (eg, contralateral occlusion erases the small benefit of CEA in asymptomatic patients whereas in symptomatic patients, it is associated with increased operative risk but persistent benefit). CEA for symptomatic patients with angiographic near-occlusion is associated with a trend toward benefit at two years, but not associated with a clear long-term benefit. Patients who underwent surgery within two weeks of their last TIA or mild stroke derive greater benefit from CEA.
- Symptomatic and asymptomatic patients undergoing CEA should be given aspirin (81 or 325 mg/d) prior to surgery and for at least three months following surgery to reduce the risk of stroke, MI, and death. Although data are not available, it is recommended that aspirin (81 or 325 mg/d) be continued indefinitely provided that contraindications are absent.
- At this time, the available data are insufficient to declare either CEA before or simultaneous with CABG as superior in patients with concomitant carotid and coronary artery occlusive disease.
- For patients with severe stenosis and a recent TIA or nondisabling stroke, CEA should be performed without delay, preferably within two weeks of the patient's last symptomatic event. There is insufficient evidence to support or refute the performance of CEA within four to six weeks of a recent moderate-to-severe stroke.
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