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A 60-year-old male presented with radiation-induced left carotid artery stenosis. Carotid endarterectomy was performed successfully without postoperative deficits. Carotid endarterectomy is the therapeutic management of choice for these lesions.
A 59-year-old male and a 74-year-old male presented with occlusion of the right internal carotid artery and stenosis at the origin of the ipsilateral external carotid artery manifesting as cerebral ischemia. External carotid endarterectomy with patch angioplasty using the internal jugular vein was performed. Special care was taken to obliterate the stump of the carotid artery using a Weck clip in one case and plication with non-absorbable sutures in the other. Cerebral blood flow in the affected hemisphere was increased after surgery and the patients remained asymptomatic. External carotid endarterectomy has several special aspects such as patch angioplasty and elimination of the stump which must be understood.
A 56-year-old man had undergone extracranial-intracranial (EC-IC) bypass surgery for occlusion of the right internal carotid artery. Six years later, he complained of transient episodes of numbness in the left arm, occurring periodically over the previous 3 months. Neuroimaging showed the right external carotid artery was severely narrowed and cerebral blood flow (CBF) was diffusely low. Endarterectomy of the right external carotid artery was performed. Postoperative CBF was markedly improved, suggesting that EC-IC bypass became effective again by endarterectomy of a parent artery.
A preliminary study was carried out on a population of twenty-five consecutive and unselected patients undergoing carotid endarterectomy. A matched control group of subjects suffering from same pathology, but unoperated, was compared to experimental sample. A battery of neuropsychological tests, the Zung Self-Rating Depression Scale and the Jachuck's Quality of Life Impairment Scale were administered one week before surgery, two weeks after (surgical sample only) and then eight months later. The research shows that carotid endarterectomy does not impair neuropsychological performances, but produces some improvement, reaching significant level in the case of Word Fluency 1 and Similarities tests; depressive scores remained substantially unchanged, while quality of life improved slightly.
INTRODUCTION: The goal of modern carotid surgery is relief of symptoms, stroke prevention, improvement in quality of life, prevention of vascular dementia, and prolongation of lifetime. OBJECTIVE: The objective of this paper was to compare the outcome of carotid endarterectomy in cervical block vs. general anesthesia in patients with occluded contralateral internal carotid artery (ICA). METHOD: One hundred patients (76 male, 24 female, mean age 60.81 years) with occluded contralateral ICA were operated from 1997-2000. Neurological symptomatology, deficiency and stroke incidence were preoperatively analyzed in two groups. Duplex-scanning, angiograms and CT-scan confirmed the diagnosis. Risk factors analysis included hypertension, diabetes, lipid metabolism disorders, smoking and history of CAD, CABG and PAOD. Morbidity and mortality were used to compare the outcome of surgery in two groups. RESULTS: There was no difference of age, gender and symptomatology between the groups. Paresis, TIA and dysphasia were most frequent. 70%-90% of ICA stenosis was seen in the majority of patients. Hypertension and smoking were dominant risk factors in these two groups. Eversion carotid endarterectomy was the most frequent technique used. In three cases out of nine that were operated under cervical block, the neurological symptoms developed just after clamping, so the intraluminal shunt was placed. Postoperative morbidity was 12% and mortality was 8%. CONCLUSION: There was no difference of preoperative parameters, surgical technique and outcome in these two groups. Without other intraoperative monitoring, cervical block anesthesia might be an option in patients with the occlusion of the contralateral ICA. However, prospective studies involving more patients are needed.
The healing of the canine carotid endarterectomy was defined at intervals from 30 minutes to 3 months after surgery by means of angiography, light microscopy, and scanning electron microscopy. Immediately after flow was established, a fibrinplatelet carpet formed on the endarterectomized surface. A typical thrombus formed on this initial layer resulting in vessel occlusion in 52% of non-heparinized animals. By 48 hours after surgery, there was little evidence of active thrombus formation, and reendothelialization from existing endothelial cells was noted. One week later, most of the mural thrombus had disappeared and re-endothelialization was well underway; by 3 months after surgery, re-endothelialization was complete. Intraoperative heparinization resulted in a striking reduction in mural thrombus formation and 100% patency rate. Vessel closure with vein-patch grafts resulted in no improvement of vessel patency. However, the results of this aspect of the study cannot be totally extrapolated to human carotid endarterectomy for the reasons discussed. The survival of the vein-patch grafts was investigated.
The purpose of this study was to determine reversal of heparin, immediately after carotid endarterectomy would have an adverse effect on the thrombogenicity of the endarterectomized vessel wall. After systemic heparinization, unilateral common carotid endarterectomies were performed under the operating microscope on 14 dogs. Half of the animals were given protamine sulfate to reverse the heparin. Three hours after resumption of blood flow, these arteries, as well as contralateral vessels used as controls for fixation technique, were perfused with glutaraldehyde and prepared for scanning electron microscopy (SEM). Thrombin clotting times were measured throughout the experiments. Sections of the endarterectomized portions viewed by SEM showed nearly total coverage of the exposed collagen of the media with flattened platelets. There were scattered leukocytes, but few erythrocytes, little fibrin, and no true thrombus. There were no difference between the animals that received heparin reversal and those that did not. A group of five additional arteries underwent the same procedure except that no heparin was given. As expected, large amount of thrombus had formed within the lumina of these control vessels by 3 hours. Since previous studies suggest that arterial thrombosis usually occurs within 3 hours of endothelial injury, the authors conclude that total reversal of heparin does not increase thrombogenicity of the endarterectomized vessel. This suggests that heparin may be safely reversed in patients to help maintain postoperative hemostasis.
Preoperative intravenous digital subtraction angiography (IV DSA) was compared with the operative findings in 54 patients who underwent a total of 57 carotid endarterectomies, to evaluate the accuracy of preoperative IV DSA in predicting the lesion found at surgery. Four studies early in the series were technically unsatisfactory, leaving 50 patients with 53 procedures for evaluation. Severe carotid artery stenosis was accurately predicted in all cases. Deep ulceration in the absence of severe carotid stenosis was reliably shown by IV DSA, although it was not reliably demonstrated by either IV DSA or carotid angiography if severe stenosis was also present. As severe carotid stenosis or deep ulceration are the major radiological indications for carotid endarterectomy, the authors have found that technically satisfactory IV DSA is an adequate preoperative imaging technique.
The authors have reviewed 150 consecutive carotid endarterectomies in 140 patients performed by three neurosurgeons. These were performed in two small community hospitals. There was an overall mortality rate of 1.3%; major or minor stroke was seen in 2.7% of patients and transient neurological dysfunction in 2.7%. Preoperative symptoms included major or minor stroke in 39.3% of patients and transient neurological dysfunction in 43.3%; 17.3% of patients were asymptomatic. The patients were continuously monitored intraoperatively with electroencephalography. There were two operative deaths, both related to myocardial infarction and both on the 2nd postoperative day. These statistics appear to compare favorably with those of series reported by major institutions. The average number of carotid endarterectomies per surgeon per year was 10. These were performed over a 7-year period (October, 1976, through November, 1983). Previous series have implied the need for higher frequency in performing the procedure to assure low morbidity and mortality rates. This series appears to offer evidence to the contrary. A key to these results has been that in 148 of the 150 operations, the primary surgeon has been assisted by one of the other two neurosurgeons. This affords the primary surgeon the benefit of excellent technical assistance, and also broadens the experience of the assisting surgeon, thereby allowing maximum experience from the small volume of cases.
In a consecutive series of 1930 carotid endarterectomies there were eight cases of postoperative intracerebral hemorrhage. One of these patients was operated on 2 weeks following cerebral infarction and had severe uncontrollable hypertension after surgery. A second patient had an intraoperative embolus and bled while fully heparinized on the 3rd postoperative day. Only one patient in the series bled into an area of documented cerebral infarction. The remainder of the cases represented hemorrhage into essentially normal brain. Seven of the eight patients with intracerebral hemorrhage had high-grade internal carotid artery stenosis preoperatively. Although several factors have contributed to the brain hemorrhages in this series of patients, postoperative cerebral hyperperfusion which often follows endarterectomy may have played an important role. Defective cerebrovascular autoregulation in chronically ischemic brain regions may predispose patients to intracerebral hemorrhage after removal of a high-grade stenosis of the internal carotid artery.
The usefulness of electroencephalographic (EEG) monitoring as well as the significance of the period of cross clamping in carotid endarterectomy have not been completely defined. In particular, the clinical importance of major EEG changes has not been fully investigated and some recent studies seem to indicate that the method has little value. As to the duration of cross clamping, there is strong evidence that occlusion times of about 15 minutes are tolerated under general anesthesia, but no information is available regarding longer periods of occlusion. The authors describe a consecutive series of 141 carotid endarterectomies in which the patients with EEG changes were shunted only when occlusion was anticipated to last longer than 30 minutes. Early major EEG changes (during the first 4 minutes) occurred in 14% of the cases. In the absence of EEG changes, long occlusion periods of 40 to 50 minutes were well tolerated. In contrast, the 20 patients with major persistent EEG changes did not tolerate protracted occlusion and three of them had immediate postoperative neurological complications. It seems that, in these circumstances, the incidence of neurological deficit is a function of the duration of cross clamping: these three patients had undergone occlusion for 15 to 30 minutes. Their deficits partially resolved. On the basis of these results it is concluded that: EEG recording is a reliable monitoring system in carotid artery cross clamping. No major strokes due to temporary carotid artery occurred in the series. The clinical significance of major persistent EEG changes is not negligible. Cross clamping for longer than 15 minutes in the presence of significant EEG alterations is potentially dangerous.
A retrospective review of carotid endarterectomies performed by the Neurosurgical Service at Massachusetts General Hospital from July, 1976, through December, 1985, disclosed 64 procedures that were performed on an emergency basis. The patients included 40 men and 24 women, with a mean age of 64 years (range 32 to 87 years). Correlation of angiographic findings with outcome revealed that of the 27 patients with severe stenosis, usually with delay in blood flow, 25 (93%) were the same or improved postoperatively; of the 11 patients with stenosis and an intraluminal filling defect (six of whom had an intraluminal clot), eight (73%) were the same or improved after surgery; of the 16 patients with complete occlusion, 14 (88%) were the same or improved (backflow was established in all cases); and of the 10 patients with moderate to severe stenosis and/or severe ulceration (including three with transient ischemic attacks who were receiving heparin), eight (80%) were the same or improved. Pre- and postoperative clinical status were graded into five categories: intact; mild deficit; moderate deficit (significant impairment but able to perform activities of daily living); severe deficit (requiring assistance for daily activities); and death. Of the 36 patients who preoperatively were intact or had mild deficits, 33 (92%) were the same or improved postoperatively, three were worse, and there were no deaths. Among 15 patients presenting with moderate deficits, 12 (80%) were the same or improved, two were worse, and one died. Of the 13 patients with severe deficits, 10 (77%) were the same or improved and three died. Two patients with sudden severe deficits associated with loss of contralateral bruit were operated on without angiography and were intact postoperatively. Of the four deaths in the total series, two were attributed to cardiac causes and two to unrelated disease processes. The indications for emergency carotid endarterectomy are discussed.
A series of 14 patients with intracerebral hemorrhage after carotid endarterectomy is reviewed. This complication occurred in 0.6% of 2362 consecutive carotid endarterectomies performed at the Mayo Clinic from 1972 through 1986. All hemorrhages occurred within the first 2 weeks after operation and were ipsilateral to the side of the operation. Eight patients died, and only two made a good recovery. Significant risk factors are hypertension and chronic hemispheric hypoperfusion with impaired autoregulation. The "normal pressure-hyperperfusion breakthrough" syndrome was considered to be operative in 12 of the 14 patients. Nine patients had documented hyperperfusion (at least 100% increase of baseline cerebral blood flow) at the time of surgery. In an additional three patients, normal perfusion-pressure breakthrough was inferred by the clinical course and radiological findings, as well as by the absence of alternative explanations. Patients at risk for postendarterectomy intracerebral hemorrhage include those who have a clinical history suggestive of hemodynamic cerebral ischemia, severe carotid stenosis with limited hemispheric collateral flow, and postendarterectomy hyperperfusion, as measured by intraoperative cerebral blood flow. To minimize the risk of hemorrhage in these patients, strict maintenance of blood pressure at normotensive or even relatively hypotensive levels during the intraoperative and early postoperative periods is advised.
The case is presented of an elderly man with an acute confusional state occurring soon after he had undergone a right carotid endarterectomy. Angiography demonstrated segmental areas of cerebral vasoconstriction and an electroencephalogram revealed periodic lateralized epileptiform discharges, both involving the right hemisphere. Cerebral hyperperfusion has been implicated in the genesis of several transient neurological syndromes following carotid endarterectomy. This case suggests that cerebral vasoconstriction may also be associated with impairment of cerebrovascular autoregulation observed after this procedure.
A case is reported of severe unilateral hemispheric edema and localized hemorrhage associated with seizures following endarterectomy of an ipsilateral high-grade carotid stenosis. Imaging studies including angiography, computerized tomography (CT), magnetic resonance imaging/angiography, and xenon-CT, suggested postoperative ipsilateral cerebral hyperperfusion. Cerebral hyperperfusion syndromes caused by a probable failure of vascular autoregulation are rare but potentially serious complications after endarterectomy. The literature on this type of complication is briefly reviewed, and the role of various imaging modalities in identification of the syndrome and in guiding management decisions is emphasized.
OBJECT: Cerebral ischemia that occurs during carotid endarterectomy is commonly monitored by means of somatosensory evoked potentials (SSEPs) and electroencephalography (EEG). The authors conducted this study to determine whether cerebral ischemia could also be reliably detected by cerebral oximetry. METHODS: Twenty-nine patients who underwent carotid endarterectomy were monitored by means of SSEPs, EEG, and cerebral oximetry with a model NIRO500 (20 patients) or INVOS3100A (nine patients) oximeter. Changes in amplitude of SSEPs were graded as follows: 0, no change; 1, decrease of less than 50%; 2, decrease of greater than 50%; and 3, 100% decrease. As measured with the NIRO500 oximeter, closing the common caro-tid artery decreased mean oxyhemoglobin levels twice as much (p < 0.005) in the group with SSEPs of 1 to 3 (-13.11+/-5.59 microM [mean+/-standard deviation], 12 patients) as in the group with SSEPs of 0 (-6.22+/-5.59 microM, eight patients). The rise in deoxyhemoglobin was also greater (p < 0.05). Two of nine patients monitored with the INVOS3100A oximeter had SSEPs of 1 and 3, and their regional saturation of oxygen (rSO2) values fell by -11.50 and -11.51, respectively. In the remaining seven patients with SSEPs of 0, the rSO2 ranged between -2.00 and -6.10 with no overlap with the group with SSEPs of I to 3. The increase in oxyhemoglobin monitored using the NIRO500 oximeter and rSO2 monitored using the INVOS3100A machine after opening the external carotid artery was less than that seen after opening the internal carotid artery. Both types of oximeters could detect cerebral ischemia but whereas false negatives occurred with the NIRO500, none was observed with the INVOS3100A. Extracranial contamination was also four times less frequent with the INVOS3100A than with the NIRO500 monitor. CONCLUSIONS: The results indicate that at least as measured with the INVOS3100A instrument, a decrease in rSO2 of -10 or more or a decrease below an rSO2 of 50 is indicative of cerebral ischemia of sufficient severity to decrease the amplitude of SSEPs.
Although the use of carotid artery stents is increasing, the management of recurrent stenosis after their placement is undefined. The authors report on a patient who underwent two left carotid endarterectomies followed by left carotid angioplasty and stent placement for recurrent stenosis. A third symptomatic recurrence was subsequently managed by placement of a saphenous vein interposition graft from the common carotid artery to the distal cervical internal carotid artery. The patient remained without hemispheric or retinal ischemia at his 5-month follow-up visit. Interposition grafting should be considered as a treatment option for carotid restenosis after initial endarterectomy and stent placement.
Cerebrovascular accident or stroke is a common cause of death and disability. Carotid endarterectomy is a surgical procedure performed to prevent ischaemic stroke. This article provides an overview of atherosclerotic carotid disease and issues involved with carotid endarterectomy.