Is Contralateral Carotid Artery Occlusion a Risk Factor for Carotid Endarterectomy?

Occlusion of the contralateral internal carotid artery (ICA) is considered to have a significant impact on the outcome of carotid endarterectomy (CEA). The purpose of this study was to review one center’s experience concerning CEA opposite an occluded ICA, to see whether results differed from those obtained in patients with patent contralateral ICA in terms of relevant neurologic complication rate (RNCR, fatal + disabling stroke), stroke-free rate, and survival rate. From January 1997 to December 2002, 1,381 patients underwent a total of 1,445 CEAs at the Department of Vascular Surgery of Padua University. Patients were divided into two groups: group A included 144 patients with occlusion of the contralateral ICA and group B consisted of 1,237 patients with a patent contralateral ICA. There was no postoperative mortality in patients of group A, while in group B, two patients died as a result of myocardial infarction and cardiac failure and one died as a direct result of perioperative stroke. Postoperative disabling strokes occurred in one (0.7%) patient in group A and 10 (0.8%) patients in group B (p > 0.5). At 72 months, there were no statistical differences between the two groups in terms of RNCR, stroke-free rate, and late death. Our results show that contralateral carotid occlusion does not reduce the safety of CEA. The efficacy in terms of RNCR, stroke-free rate, and late survival is no different in patients with contralateral carotid occlusion.     

Carotid endarterectomy in female patients: are the concerns of the Asymptomatic Carotid Atherosclerosis Study valid?

OBJECTIVES: Although the results of the Asymptomatic Carotid Atherosclerosis Study clearly demonstrated the benefit of surgical over medical management of severe carotid artery stenosis, the results for women in particular were less certain. This was to some extent because of the higher perioperative complication rate observed in the 281 women (3.6% vs 1.7% in men). The objective of this study was to review a large experience with carotid endarterectomy in female patients and to determine whether the perioperative results differed from those of male patients. METHODS: A review was conducted of a prospectively compiled database on all carotid endarterectomies performed between 1982 and 1997. Operations performed in 991 female patients were compared with those performed in 1485 male patients. RESULTS: Female patients had a significantly lower incidence of diabetes, coronary artery disease, and contralateral carotid artery occlusion than did male patients. Female patients had a significantly higher incidence of hypertension. There were no significant differences in the age, smoking history, anesthetic route, shunt use, or clamp tolerance between the two groups. Of 991 female patients, 659 (66.5%) had preoperative symptoms, whereas 332 (33.5%) cases were performed for asymptomatic stenosis. Among 1485 male patients, 1041 (70.1%) had symptoms, and 444 (29.9%) were symptom free before surgery. There were no significant differences noted in the perioperative stroke rates between men and women overall (2.3% vs 2.4%, P =.92), or when divided into symptomatic (2.5% vs 3.0%, P =.52) and asymptomatic (2.0% vs 1.2%, P =.55) cases. CONCLUSIONS: Carotid endarterectomy can be performed with equally low perioperative stroke rates in men and women in both symptomatic and asymptomatic cases. In this series, symptom-free female patients had the lowest overall stroke rate. The concerns of the Asymptomatic Carotid Atherosclerosis Study regarding the benefit of carotid endarterectomy in female patients should therefore not prevent clinicians from recommending and performing carotid endarterectomy in appropriately selected symptom-free female patients.     

Carotid endarterectomy: are we under-performing?

An audit of the number of carotid endarterectomies performed over the last 4 years was performed in the south western region. For the years 1990, 1991, 1992 and 1993 the number of cases were 126, 165, 165 and 164 respectively. It is estimated for this region that about 600 operations should be carried out per annum. This under-performance may reflect a lack of knowledge about the potential benefits of surgery.     

Carotid endarterectomy; local or general anaesthesia?

OBJECTIVES: to review the evidence for theoretical and clinical benefits of local or general anaesthesia for carotid endarterectomy. METHODS: literature review. RESULTS: animal studies suggest cerebral protection by a variety of general anaesthetic agents but clinical evidence is lacking. There is some clinical evidence that normal cerebral protective reflexes are preserved with local anaesthesia. Shunt insertion is the most widely used method of providing cerebral protection with awake testing the most reliable monitoring technique for the identification of ischaemia. There are therefore theoretical arguments for a reduced risk of perioperative stroke when local anaesthesia is used and this is supported by a meta-analysis of non-randomised studies. Intraoperative blood pressure is always higher with local anaesthesia but the incidence of postoperative haemodynamic instability seems to be independent of anaesthetic technique. There is little evidence that myocardial ischaemia is more common with either anaesthetic technique but meta-analysis of non-randomised again suggests fewer cardiac complications with local anaesthesia. Cranial nerve injury and haematoma formation may be less common with local anaesthesia but the evidence is weak. There is no evidence that surgery is more difficult with local anaesthesia or that it is poorly tolerated by the patients. CONCLUSIONS: there are theoretical arguments and clinical evidence that the outcome from carotid endarterectomy may be better when local anaesthesia is used with no significant disadvantages. An appropriately designed randomised trial is required to confirm this.     

Carotid surgery in octogenarians: why not?

The latest studies have clearly demonstrated the efficacy of carotid endarterectomy. However, most of these studies excluded patients over the age of 80. Some authors question the efficacy of and indication for endarterectomy in octogenarians. We therefore compared our results for endarterectomies on patients aged under and over 80. The author reviewed 475 carotid endarterectomies that he himself performed between July 1, 1990 and February 28, 2001; 72 of these procedures were carried out on 65 patients (15%) aged 80 and over. Both perioperative neurological events and mortality were studied. The outcome of carotid endarterectomy in both patient population groups was comparable; more than 70% of octogenarians were still alive 4 years later the same indications for carotid endarterectomy should therefore be applied to octogenarians.     

Carotid stenosis: Endarterectomy or angioplasty and stenting?

Opinion statement Atherosclerotic narrowing of the proximal internal carotid artery is an important mechanism in ischemic stroke. Optimal medical management of internal carotid stenosis includes antiplatelet agent and statin administration, blood pressure reduction, weight control, and smoking cessation. Decisions regarding the use of invasive procedures to treat carotid disease—specifically carotid endarterectomy and carotid angioplasty and stenting—must weigh the long-term risk reduction in ipsilateral ischemic stroke against the immediate intervention risks. Clinical trials evaluating the benefits of carotid endarterectomy were conducted before widespread use of statins and newer blood pressure-lowering agents such as angiotensin-receptor blockers; it is unclear what impact this may have had on trial results. Regardless, carotid endarterectomy is clearly superior to medical therapy for patients with symptomatic severe stenosis. Conversely, the benefit from endarterectomy is muted in individuals with symptomatic moderate stenosis or asymptomatic stenosis, and decisions regarding surgical intervention must incorporate surgeon proficiency and patient comorbidity. Currently, there is a lack of evidence to support the use of carotid artery angioplasty and stenting in the routine management of carotid disease. Selected patients with severe symptomatic stenosis for whom endarterectomy cannot be safely performed may still benefit from endovascular management. However, it is unlikely that asymptomatic patients or symptomatic patients with moderate stenosis considered at high risk for endarterectomy would benefit from any intervention.     

Carotid stents: which is the best option?

Nowadays, carotid artery stenting (CAS) offers a potential alternative to carotid endarterectomy (CEA). CAS main advantages over CEA are the less invasive approach and the almost equal performance to CEA in terms of stroke prevention and complications. One of the most important factors which played significant role to CAS evolution is the progress in design of modern materials, especially stents. Today, several types of dedicated carotid stents have specific mechanical properties, which provide stents with individual characteristics making each of them suitable for specific carotid lesions and anatomies. The present review analyses the specific design and construction of modern stents, trying to point out their particular mechanical properties and characteristics. Additionally, it presents all available data published on comparison between different stent designs with the intention to identify which carotid stent is the best option for particular patient and lesion characteristics.     

Carotid endarterectomy: who is the high-risk patient?

The role of carotid endarterectomy in the prevention of stroke was validated by two randomized clinical trials, the North American Symptomatic Carotid Endarterectomy (NASCET) and the Asymptomatic Carotid Atherosclerosis Study (ACAS). However, these trials excluded patients at high risk for perioperative stroke and other morbidity, raising concerns for the applicability of the trial results to the general population. Some have also suggested these "high-risk" patients are better suited for carotid artery stenting with the belief that stenting has lower morbidity and mortality. In this article, we review many of the commonly accepted high-risk factors for carotid endarterectomy (CEA) and examine their outcomes. High-risk patients are more common than generally believed and their outcomes may be the same with carotid endarterectomy as it is with carotid stenting. Truly "high-risk" patients with shortened life expectancy are best served with no intervention.     

Carotid endarterectomy – Is intensive care unit care necessary?

Purpose: The purpose of this study was to determine whether postoperative intensive care unit care is necessary for all patients undergoing carotid endarterectomy and whether a subgroup of patients at low-risk not requiring treatment in the intensive care unit could be identified. Methods: Case control analysis of random numbers sample over the last decade of 50% of patients undergoing isolated carotid endarterectomy at a tertiary care hospital. One hundred twenty-nine patients undergoing carotid endarterectomy were identified. Preoperative risk factors, intraoperative course, intensive case unit interventions including vasoactive agents, myocardial ischemia/infarction, arrhythmias, bronchospasm, reintubation, neurologic events, and need for reoperation, were recorded. Timing of interventions, length of stay in intensive care unit, and postoperative course were all recorded. Financial impact was assessed. Results: Among 129 patients only 31 patients did not require intensive care unit interventions. A multivariate linear regression analysis demonstrated a model in which a preoperative history of hypertension, myocardial infarction, arrhythmia, and chronic renal failure were 83% predictive of the need for an intensive care unit bed. Specifically, patients could be stratified into a low-risk group before the operation by less than four risk factors. Additionally, all patients requiring interventions or with adverse outcomes were identified by the eighth postoperative hour. Conclusions: In preoperative scheduling of intensive care unit beds, patients with less than four risk factors can be stratified to monitoring beds and those with greater than or equal to four can be stratified to intervention beds. After 8 hours, if no interventions are necessary or adverse outcomes occur, then floor recovery is safe. Patients who satisfy this algorithm would save 50% of current intensive care unit charges. (J VASC SURG 1994;20:403-10.)     

Carotid artery stenosis: Routine predilatation or direct stenting?

Stenting is a potential alternative treatment for carotid artery stenosis. Direct stenting may, theoretically, reduce the risk of embolism by minimizing plaque manipulation before tissue scaffolding is achieved. The results of direct carotid stenting are reported and compared with those of stenting with predilatation. One hundred and seventy‐four carotid artery stenoses were treated from July 1998 to February 2002, with 84 lesions directly stented (Group 1) and the other 90 lesions stented after predilatation (Group 2). The criteria for direct stenting were minimal luminal diameter (MLD) > 1 mm and no visible thrombus angiographically. Technical success rates of the two groups were both 100%, without any cross‐over. Reference vessel diameter and lesion length did not differ between the two groups. In Group 1, diameter stenosis was lower (79 ± 8 vs 92 ± 7%, P < 0.001) and MLD was larger (1.1 ± 0.5 vs 0.4 ± 0.4 mm, P < 0.001) than that in Group 2, but the final MLD (4.7 ± 0.9 vs 4.7 ± 0.9 mm, P = 0.94) of the two groups were not statistically different. The periprocedural ipsilateral stroke or death rates were also similar in the two groups (2/84 vs 4/90, P = 0.68). It was concluded that if the MLD of carotid stenosis is larger than 1 mm and no thrombus is present, direct stenting could be carried out safely with results comparable to that of stenting after predilatation.      

Carotid artery stenting: which stent for which lesion?

The different geometries and working principles of carotid stents (nitinol or cobalt chromium, open- or closed-cell configuration) provide each product with unique functional properties. The individual characteristics of each device may make it an attractive choice in one circumstance but render it less desirable in other situations. In approximately 75% of all procedures, all types of stents will achieve similar outcomes, making adequate device selection unnecessary. For the remaining quarter, careful preoperative screening is mandatory. In addition to eventual access issues, the choice of the optimal carotid stent depends mainly on arterial anatomy and lesion morphology. When treating a tortuous anatomy, stents with a flexible and comformable open-cell configuration are preferred. In arteries with a significant mismatch between common carotid artery and internal carotid artery diameter, cobalt chromium (Elgiloy) or tapered nitinol stents are selected. Lesions with suspected high emboligenicity are best covered with stents with a closed-cell configuration, whereas highly calcified lesions need treatment with nitinol stents. Thorough knowledge of the characteristics, advantages and disadvantages, and working principles of the different available stents is mandatory to optimally select the materials to be used for patients eligible for carotid revascularization.     

Carotid artery stenting: which stent for which lesion?

Although some early reports describe angiographic as well as clinical success for balloon angioplasty alone in the treatment of carotid occlusive disease, most interventionists prefer stent-assisted balloon angioplasty because of the purported advantages, such as avoiding plaque dislodgement, intimal dissection, elastic vessel recoil and late restenosis. Mainly because of the different characteristics of each carotid artery segment, different types of stents are preferred. A carotid artery lesion located in the intrathoracic brachiocephalic trunc or common carotid artery would need a different stent to a lesion at the carotid bifurcation or a lesion of an intracerebral branch of the internal carotid artery.     

Carotid Artery Stenting: Which Stent for Which Lesion ?

Although some early reports describe angiographic as well as clinical success for balloon angioplasty alone in the treatment of carotid occlusive disease, most interventionists prefer stent-assisted balloon angioplasty because of the purported advantages, such as avoiding plaque dislodgement, intimal dissection, elastic vessel recoil and late restenosis. Mainly because of the different characteristics of each carotid artery segment, different types of stents are preferred. A carotid artery lesion located in the intrathoracic brachiocephalic trunc or common carotid artery would need a different stent to a lesion at the carotid bifurcation or a lesion of an intracerebral branch of the internal carotid artery.