Carotid endarterectomy contralateral to an occluded carotid artery: perioperative risk and late results

To define better the short-term risk and long-term benefit of carotid endarterectomy opposite an occluded carotid artery, we reviewed our experience since 1961. Angiographic data are available for 598 of 670 (89.3%) patients in our carotid registry. In 63 (10.5%) patients the internal or common carotid artery on the side opposite the endarterectomy was occluded. All operations were carried out under general anesthesia with selective shunting based on electroencephalographic criteria. Shunting was required in 29 of 63 (46.0%) patients with contralateral occlusion and 72 of 535 (13.5%) control subjects (p less than 0.0001). Perioperative strokes occurred in 3 of 63 (4.8%) patients with contralateral occlusion and 14 of 535 control subjects (2.6%) (p = 0.23). Perioperative death occurred in 0 of 63 patients with contralateral occlusion and 6 of 535 (1.1%) control subjects (p = 0.40). Life-table cumulative stroke-free rates at 1, 5, and 10 years were 95.2%, 91.0%, and 76.2% in the group with contralateral occlusion and 96.0%, 89.4%, and 84.1% in control subjects (p = 0.25). Life-table cumulative survival rates at 1, 5, and 10 years were 93.1%, 80.8%, and 75.4% in the group with contralateral occlusion and 94.8%, 77.0%, and 57.9% in control subjects (p = 0.58). Carotid endarterectomy contralateral to an occluded carotid artery may be carried out with acceptable risk and late stroke-free and survival rates comparable to those seen in other patients who have undergone carotid endarterectomy.     

Carotid endarterectomy contralateral to carotid artery occlusion: analysis from a randomized study

BACKGROUND AND AIMS: Many studies have reported the benefits of carotid endarterectomy (CEA) contralateral to an occluded internal carotid artery (ICA), with varying results. This study analyzed perioperative and late outcomes in a recent trial in which patients were randomized to carotid eversion endarterectomy (CEE) or traditional CEA with patching (CEAP). PATIENTS AND METHODS: In 336 primary CEAs (310 patients) 68 were contralateral to an occluded ICA (group I). The remaining 268 CEAs served as control group (group II). All patients underwent clinical follow-up and duplex ultrasonography at 1, 6, and 12 months and every year thereafter. Endpoints of the study were early and late neurological events, and deaths. RESULTS: Group I had a significantly higher incidence of perioperative electroencephalic changes and need for shunting. The perioperative stroke rate in group I was almost three times as high as in group II, but the difference was not significant. Similarly, the perioperative minor neurological event and death rates, as with the cumulative stroke-free and survival rates at 1, 3, and 5 years, were comparable in the two groups. CONCLUSIONS: CEA contralateral to an occluded ICA can be implemented with perioperative stroke and mortality rates and late stroke-free and survival rates comparable to CEA with no contralateral ICA occlusion.     

Results of carotid endarterectomy in patients with contralateral internal carotid artery occlusion from the Mid-America Vascular Study Group and the Society for Vascular Surgery Vascular Quality Initiative

ObjectiveCarotid endarterectomy (CEA) is among the most commonly performed vascular procedures. Some have suggested worse outcomes with contralateral internal carotid artery (ICA) occlusion. We compared patients with and patients without contralateral ICA occlusion using the Society for Vascular Surgery Vascular Quality Initiative database.MethodsDeidentified data were obtained from the Vascular Quality Initiative. Patients with prior ipsilateral or contralateral CEA, carotid stenting, combined CEA and coronary artery bypass graft, or <1-year follow-up were excluded, yielding 1737 patients with and 45,179 patients without contralateral ICA occlusion. Groups were compared with univariate tests, and differences identified in univariate testing were entered into multivariate models to identify independent predictors of outcomes and in particular whether contralateral ICA occlusion is an independent predictor of outcomes.ResultsPatients with contralateral ICA occlusion were younger and more likely to be smokers; they were more likely to have chronic obstructive pulmonary disease, preoperative neurologic symptoms (56% vs 47%), nonelective CEA (16% vs 13%), and shunt placement (75% vs 53%; all P < .001). The 30-day ipsilateral stroke risk was 1.3% with vs 0.7% without contralateral ICA occlusion (P = .004). The 30-day and 1-year survival estimates were 99.0% ± 0.5% and 94.1% ± 1.1% with vs 99.6% ± 0.1% and 96.0% ± 0.2% without contralateral ICA occlusion (log-rank, P < .001). Logistic regression analysis identified prior neurologic event (P = .046), nonelective surgery (P = .047), absence of coronary artery disease (P = .035), and preoperative angiotensin-converting enzyme inhibitor use (P = .029) to be associated with 30-day ipsilateral stroke risk, but contralateral ICA occlusion remained an independent predictor in that model (odds ratio, 2.29; P = .026). However, after adjustment for other factors (Cox proportional hazards), risk of ipsilateral stroke (including perioperative) during follow-up was not significantly greater with contralateral ICA occlusion (hazard ratio, 1.21; P = .32). Results comparing propensity score-matched cohorts mirrored those from the larger data set.ConclusionsThis study demonstrates likely clinically insignificant differences in early stroke or death in comparing CEA patients with and those without contralateral ICA occlusion. After adjustment for other factors, contralateral ICA occlusion was not associated with a greater risk of ipsilateral stroke (including perioperative) in longer follow-up. Mortality was greater with contralateral ICA occlusion, and this difference was more pronounced at 1 year despite younger age of the contralateral ICA occlusion group. CEA risk remains low even in the presence of contralateral ICA occlusion and appears to be explained at least in part by other factors. CEA should still be considered appropriate in the face of contralateral ICA occlusion.     

Does contralateral carotid occlusion influence neurologic fate of carotid endarterectomy?

Divergent opinions regarding operative risks and late prognosis of patients undergoing endarterectomy for carotid stenosis with contralateral carotid occlusion have prompted a review of the experience at Emory University Hospital from Jan. 1, 1978, through Dec. 31, 1982. Fifty-four patients (37 men, 17 women; mean age 63 years) who underwent carotid endarterectomy (CEA) with contralateral carotid occlusion (group I) were compared with 410 demographically similar patients without contralateral carotid occlusion (group II) who underwent 503 CEAs during the same interval. CEA indications in group I were the following and were proportionately similar to those of group II: hemispheric transient ischemic attacks, 22 patients; asymptomatic stenosis, 12 patients; nonhemispheric symptoms, 11 patients; previous cerebral infarction, eight patients; and vascular tinnitus, one patient. General anesthesia, routine intraluminal shunting, systemic heparinization, and arteriotomy closure without patch were routinely employed in both groups. Three patients in group I suffered permanent neurologic deficits after operation (5.6%) and two had transient postoperative deficits with complete recovery. Ten patients (2.0%) in group II suffered permanent neurologic deficits and 10 patients experienced transient neurologic events after operation. Neither the transient nor the permanent neurologic deficit rates were statistically different (p greater than 0.05; Fisher exact test) in the two groups. Operative mortality rates for group I and group II were 0% and 0.8%, respectively, and were not significantly different (p greater than 0.10; Fisher exact test). Late postoperative ischemic brain infarctions occurred in two patients in group I (3.8%) and in 13 patients (3.6%) in group II (p greater than 0.10; Fisher exact test). Kaplan-Meier survival analyses were virtually identical in both groups, with the majority of deaths caused by cardiac occlusion may undergo CEA with morbidity and mortality rates similar to those without contralateral occlusions. Contralateral carotid occlusion does not necessarily portend an unfavorable early or late prognosis after CEA.     

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.     

Cerebral blood flow in relation to contralateral carotid disease, an MRA and TCD study.

OBJECTIVE: to describe redistribution of cerebral blood flow in patients with severe internal carotid artery (ICA) stenoses in relation to contralateral ICA disease. METHODS: sixty-six patients scheduled for carotid endarterectomy (CEA) were grouped according to severity of contralateral stenosis (<30% [group I]; 30-69% [group II]; 70-99% [group III]; occlusion [group IV]. Transcranial Doppler (TCD) and magnetic resonance angiography (MRA) investigations were performed preoperatively. RESULTS: TCD demonstrated a reversed flow in the contralateral anterior cerebral artery (A(1)segment) and ophthalmic artery in three-quarters of group IV patients (p <0.0001). Group IV patients also exhibited decreased blood flow velocity in the contralateral middle cerebral artery (p =0.001). MRA showed increased ipsilateral ICA and basilar artery (BA) blood flow volumes (Q-flows) in group IV patients when compared to the other groups (p <0.001). No changes in total Q-flow (ICAs+BA) were found. CONCLUSIONS: in patients considered for CEA, the severity of the contralateral ICA disease is an important determinant of the pattern of blood flow redistribution through the anterior communicating pathway and ophthalmic artery. Significant flow redistribution through the posterior communicating pathway occurs especially in patients with contralateral ICA occlusion.     

Surgical treatment of internal carotid artery occlusion

PURPOSE: Nonoperative treatment of recent internal carotid artery (ICA) occlusion is associated with increased recurrent stroke rates. We analyzed our results of carotid endarterectomy (CEA) for treatment of symptomatic recent ICA occlusion to evaluate its feasibility, safety, and outcomes. METHODS: From 1990 to 2002, all patients with transient ischemic attack (TIA), amaurosis fugax, and minor stroke underwent duplex ultrasound (US) scanning and arteriography to confirm the diagnosis of ICA occlusion. Within 2 weeks of symptom onset, patients underwent operative exploration with attempted CEA. ICA occlusion was detected at preoperative angiography and confirmed at surgery. Patients with extensive ICA plaque not amenable to endarterectomy underwent external CEA with ICA ligation. RESULTS: Over 12 years, 87 patients with symptomatic ICA occlusion underwent 90 operations for ICA exploration. In 30 patients (18 men, 12 women) with TIA (45%), amaurosis fugax (19%), or minor stroke (36%), CEA to treat ICA occlusion was technically successful. There was 1 postoperative stroke, 2 asymptomatic internal carotid occlusions, and no restenoses (mean follow-up, 26 months; range, 1-93 months). In 57 patients (37 men, 20 women) with TIA (41%), amaurosis fugax (27%), or stroke (32%) in whom CEA was unsuccessful, external CEA was performed. In this group there were no postoperative strokes, 2 asymptomatic external carotid artery occlusions, and 1 restenosis (>70%) (mean follow-up, 22 months; range, 1-73 months). There were no late strokes in either group. CONCLUSION: Operative exploration and endarterectomy to treat symptomatic ICA occlusion is feasible and safe. Patients with symptomatic ICA occlusion should be considered candidates for CEA.     

Carotid endarterectomy with routine electroencephalography and selective shunting: Influence of contralateral internal carotid artery occlusion and utility in prevention of perioperative strokes

OBJECTIVE: Carotid endarterectomy (CEA) is associated with a risk of cerebral ischemia during carotid clamping, particularly in the face of contralateral internal carotid artery (ICA) occlusion. We examined the results of CEA with continuous electroencephalography in patients without and with contralateral ICA occlusion. DESIGN AND SETTING: We reviewed 564 primary CEAs with routine electroencephalography and general anesthesia performed between April 1, 1989, and March 31, 1999, in a community teaching medical center. Main outcome measures were perioperative stroke, temporary lateralizing neurologic deficit, and death. Shunts were placed primarily for significant electroencephalographic changes after carotid clamping but also selectively for contralateral ICA occlusion, prior stroke, or surgeon choice. CEA was performed for asymptomatic disease in 35% of cases. RESULTS: Significant electroencephalographic changes occurred in 16% versus 39% (P <.001) and shunts were placed in 13% versus 55% (P <.001) of patients with patent (n = 507) versus occluded contralateral ICA (n = 57), respectively. The fraction of CEAs with significant electroencephalographic changes during clamping was stable, but shunt use declined slightly over time as our confidence in electroencephalography increased. Patches were placed more often (86% versus 65%; P =.002), but other operative details were similar when the contralateral ICA was occluded. Five early (30 days) strokes (0.9%) and eight early temporary postoperative neurologic events (1.4%) occurred, all ipsilateral to CEA and all after the patient left the operating room with none in patients with contralateral ICA occlusion. Two perioperative deaths occurred, one in a patient without and one in a patient with contralateral ICA occlusion. Neither of these deaths was related to ipsilateral stroke. No increase in stroke rate with decreased shunt use over time was seen. CONCLUSION: Routine use of electroencephalography was associated with apparent complete elimination of intraoperative strokes and less than 1% risk of perioperative strokes. These observations appear to be true even in the face of contralateral ICA occlusion. Electroencephalography is a sensitive detector of cerebral ischemia and a valuable tool for determination of need for shunting during CEA. Surgeons should consider routine use of electroencephalography and selective shunting for significant electroencephalographic changes with clamping.     

Natural history of carotid artery occlusion contralateral to carotid endarterectomy

BACKGROUND: The natural history of patients with carotid artery occlusion is controversial. A few studies have concluded that patients with internal carotid artery occlusion carry a high risk of neurologic events. None of these previously reported studies analyze the natural history of internal artery occlusion contralateral to carotid endarterectomy (CEA), except for a small series including a subset of patients from two randomized trials, the Asymptomatic Carotid Atherosclerosis Study and the North American Symptomatic Carotid Endarterectomy Trial. This study analyzes the natural history of patients with carotid artery occlusion contralateral to CEA, specifically assessing long-term neurologic events occurring in the hemisphere associated with the occluded carotid artery. METHODS: Of the 599 CEAs in 544 patients that were included in two previously updated prospective studies, 63 patients had contralateral internal carotid artery occlusion, and their perioperative and long-term outcomes were evaluated. A Kaplan-Meier analysis was used to estimate the rate of freedom from late stroke occurring in the hemisphere ipsilateral to the occluded carotid artery. The stroke-free survival rate was also noted. RESULTS: Mean follow-up was 58 months (range, 1 to 147 months). One perioperative stroke (1.6%) occurred, which was not in the cerebral hemisphere ipsilateral to the occluded carotid artery. Two late strokes (3.2%) and nine transient ischemic attacks (TIAs) (14.3%) occurred involving the hemisphere of the occluded carotid artery. There were also three late TIAs (4.8%) and no late strokes involving the hemisphere supplied by the operative site. There were a total of 14 late deaths. Fifteen patients had late > or =50% restenosis of the operative side. Six of these had neurologic events (TIA/stroke) involving the hemisphere of the occluded carotid artery, in contrast to five of 48 patients with no restenosis who had neurologic symptoms (P < .001). Freedom from late strokes in the hemisphere ipsilateral to the occluded carotid artery at 1, 3, 5, and 10 years was 98%, 96%, 96%, and 96%, respectively. The stroke-free survival rates at 1, 3, 5, and 10 years were 90%, 87%, 80%, and 59%, respectively. CONCLUSIONS: The natural history of carotid artery occlusion contralateral to CEA is relatively benign. This may suggest a protective effect of carotid endarterectomy on the cerebral hemisphere ipsilateral to the carotid occlusion from late strokes.     

Natural history of symptomatic and asymptomatic carotid artery occlusion contralateral to carotid endarterectomy: a prospective study

The natural history of carotid occlusion (CO) has generally been analyzed in the presence of a contralateral patent but diseased internal carotid artery (ICA). Few previous studies have focused on the fate of CO contralateral to the side of a prior carotid endarterectomy (CEA). The aim of this study was to analyze the mortality rate and the incidence of cerebrovascular events in the hemisphere ipsilateral to CO (HICO) in patients who had undergone contralateral CEA. The 30-day and long-term outcomes of 153 consecutive patients who had CEA for severe symptomatic and asymptomatic ICA lesions contralateral to a symptomatic or asymptomatic CO over a 15-year period were considered. The endpoints of the study were mortality and neurological events in the HICO. Overall, the 30-day mortality and stroke rates were 0.6% (1/153) and 1.9% (3/153), respectively; the only death was stroke-related and the stroke was ipsilateral to the operated side. The other 2 strokes were ipsilateral to a symptomatic CO. The follow-up was completed for all patients (mean, 7.7 years; range, 1-172 months). Overall, there were 4 late strokes (2.6%), one of them lacunar in a patient with a symptomatic CO, whereas the other 3 were atheroembolic and ipsilateral to the operated ICA. The risk of late stroke in the HICO at 5 and 12 years was 2%. Overall, there were 19 late deaths, none of them stroke-related. CO, with or without symptoms, contralateral to CEA could be considered a locally benign condition in the long term.     

Carotid endarterectomy in patients with contralateral internal carotid artery occlusion without intraoperative shunting

BACKGROUND: Controversy about the optimal method of performing a carotid endarterectomy (CEA) exists despite its widespread application and support from various randomized clinical trials. Many surgeons selectively or routinely use electroencephalography (EEG) monitoring as well as shunting when performing this operation. ETHODS: We conducted this retrospective study to assess the maximum carotid clamp time without shunting or EEG monitoring during a CEA without the development of neurological deficits in an already compromised cerebral circulation. RESULTS: Fifteen consecutive patients who underwent CEAs between 1988 and 1999 met our criteria of angiographically documented ipsilateral internal carotid artery (ICA) stenosis with contralateral ICA occlusion. The patient presentations included asymptomatic (14%), transient ischemic attack (TIA) (50%), and stroke (36%). All patients were operated under general anesthesia without shunting and only 4 patients underwent EEG monitoring. On angiography, all 15 patients had ipsilateral ICA stenosis (70-99%) and contralateral occlusion. In 54% of patients, the vertebral arteries (VAs) were both patent, while in 46% of patients only 1 VA was patent. Eighty-five percent of patients had at least 1 patent anterior communicating (Pcomm) artery, while 15% had nonvisualized Pcomm arteries bilaterally. Of the 15 patients, 14 had a patent anterior communicating artery. The mean clamp time of the CCA was 18.5 minutes (range 14-30 minutes). None of the 15 patients had new neurological changes immediately postoperatively or during the 6 weeks of follow-up. CONCLUSION: We propose that shunting may not be necessary during CEA for high-grade stenosis with contralateral ICA occlusion, presumably because of adequate distal small vessel collaterals.     

Magnetic resonance angiography minimizes need for arteriography after inadequate carotid duplex ultrasound scanning

PURPOSE: We prospectively evaluated whether magnetic resonance angiography (MRA) enabled definition of cerebrovascular anatomy after indeterminate or inadequate results at duplex ultrasound scanning to facilitate patient selection for carotid endarterectomy (CEA) and for technical planning. METHODS: After implementation of a protocol in October 1998 to minimize use of cerebral arteriography, MRA (arch/cervical two-dimensional and cranial three-dimensional time of flight technique) was performed in 138 consecutive patients with cerebrovascular occlusive disease and inconclusive duplex scans obtained by an ICAVL-approved laboratory. The ability of MRA to define anatomic features unresolved at duplex scanning was compared between categories of duplex scan inadequacies. Operative outcome was compared between patients requiring MRA before CEA (n = 66) and a concurrent cohort undergoing CEA on the basis of duplex scan results only (n = 69). RESULTS: Incomplete imaging of the carotid bifurcation, because of high bifurcation, long (>3 cm) internal carotid artery (ICA) plaque, or calcific shadows, was the most common reason for inadequate duplex scans (n = 74, 53%), followed by borderline severe ICA disease (23.17%), suspected extracervical disease (supra-aortic trunk, vertebral, or intracranial, 22, 16%), ICA near- occlusion (12.9%), and diffuse recurrent stenosis (7.5%). MRA enabled resolution of duplex scan inadequacies in 95% of patients with disease confined to the carotid bifurcation, and 90% of all patients, but was least accurate for delineation of extracervical lesions (77%) and near-occlusions (75%). In 5 of 8 patients (6%) arteriography was performed to determine operability of ICA near-occlusion or extracervical lesions. Combined stroke and death rates after CEA were not statistically different (P =.3) between patients requiring MRA (3 of 66, 4.6%) and the concurrent group in whom MRA was performed solely on the basis of duplex results (1 of 69, 1.5%). However, intraoperative technical adjustments (anatomy that precluded shunt use, extended endarterectomy length, ICA shortening due to tortuosity) were planned in 71% of patients (12 of 17) with MRA-defined anatomy, but only 36% of patients (4 of 11) with long CEA on the basis of duplex results only (P =.08). CONCLUSION: MRA replaces the need for cerebral arteriography in most patients after inadequate carotid duplex scanning. Delineation of cerebrovascular anatomy at MRA assists in determination of CEA candidacy and operative planning.     

Carotid endarterectomy in awake patients with contralateral carotid artery occlusion.

OBJECTIVES: Patients with severe stenosis of an internal carotid artery with contralateral occlusion (ICO) are at an increased risk for stroke, and therefore surgical treatment is usually recommended. Carotid endarterectomy (CEA) under regional anesthesia enables constant monitoring of neurologic status and selective shunting in cases of clinically evident cerebral ischemia. In this study, we assess the selective use of shunts based solely on changes in neurological status in awake patients with ICO undergoing CEA as well as their complication rates. METHODS: During 1996-1998, we studied intraoperative findings and results of CEA under regional anesthesia with clinical monitoring of neurological status in two groups: (1) patients with stenosis (> 70% by NASCET) and contralateral occlusion (n = 50) and (2) patients with stenosis and no contralateral occlusion (n = 94). RESULTS: Shunt insertion was required in 42% of group 1, and 6% in group 2. All of the patients in group 1 requiring shunts had stump pressures < 50 torr. The average stump pressure of group 1(40 torr) was significantly lower than that of group 2 (75 torr), and was also lower than that of patients with severe contralateral stenosis (35 patients, 76 torr). Perioperative stroke rates were identical in both groups (2.1%). CONCLUSION: Since ICO patients are at a high risk for brain ischemia during ICA clamping, they require shunt insertion frequently. Patients with no contralateral occlusion require shunting at a much lower rate - even in the presence of severe contralateral stenosis. Regional anesthesia allows for early detection of brain ischemia and therefore, the perioperative results in both groups are similar.     

Improvement of carotid blood flow after carotid endarterectomy--evaluation using intraoperative ultrasound flow measurement.

OBJECTIVES: to examine the relationship between the degree of extracranial internal carotid artery (ICA) stenosis and changes in the ipsilateral ICA blood flow after carotid endarterectomy (CEA). MATERIALS AND METHODS: in a prospective study we studied 51 patients with unilateral 60-99% ICA stenosis (median degree 84%, asymptomatic stenosis n = 13, symptomatic stenosis n = 38). The degree of ICA diameter stenosis was determined by ex-vivo plastination of the surgically removed atherosclerotic specimen and video-assessed planimetry. Intraoperative transit time ultrasound flow measurements of the carotid arteries were performed before and after CEA. Blood flow changes were assessed by mathematical approximations. Statistics were done by use of the Wilcoxon signed Rank test. RESULTS: common carotid artery (CCA) and ICA median blood flow increased after CEA from 370 and 130 ml/min to 450 and 282 ml/min, respectively (p <.001). The relative increase of ICA blood flow was 5% and 18% for 60-69% and 70-79% ICA stenosis (n.s.) but 70% and 247% for 80-89% and 90-99% stenosis (p <.001 each). Mathematical evaluation (fourth-polynomal function) determined a significant increase of carotid blood flow after CEA in ICA stenosis of > or =82.3%. CONCLUSIONS: in the absence of severe contralateral ICA occlusive disease a significant increase of ipsilateral ICA blood flow by CEA can be expected in patients with an ICA stenosis of > or =82.3% (linear degree of stenosis, ECST criteria).     

转流管在颈动脉内膜切除术中的应用(附11例报告)

目的:评价转流管在颈动脉内膜切除术中的所提供保护作用。方法:回顾性分析本科2002年10月以来11例施行颈动脉内膜切除术中使用转流管的经验,此11例病人全部合并对侧颈内动脉闭塞或重度狭窄,均在颈动脉转流管保护下完成手术。结果:术中、术后无死亡,且无中风等严重并发症发生。结论:在严格掌握适应证的前提下,颈动脉内膜切除术中使用转流管是安全的,对脑组织具有良好的保护作用。     

Outcome in Patients with Symptomatic Occlusion of the InternalCarotid Artery

OBJECTIVES: to assess whether the risk of recurrent ischaemic stroke in patients with symptomatic internal carotid artery (ICA) occlusion has changed over the past decades, to determine risk factors for the occurrence of ischaemic stroke and to assess the risk of endarterectomy (CEA) of a severe contralateral ICA stenosis. DESIGN: retrospective cohort study. PATIENTS AND METHODS: patients with symptomatic ICA occlusion were identified from duplex registry files between 1991 and 1995. Information was obtained on vascular risk factors, performance of CEA for a contralateral ICA stenosis and on recurrence of ischaemic stroke. The rate of complications occurring within 30 days after CEA of the contralateral ICA in patients with symptomatic ICA occlusion was compared with the risk of CEA in patients with asymptomatic ICA occlusion and severe contralateral ICA stenosis (symptomatic or asymptomatic). RESULTS: ninety-seven patients were identified. Mean follow-up time was 26 months. The annual risk of (non-)fatal stroke was 5.3% for all strokes (95% CI 2. 9%-9.6%) and 3.8% for ipsilateral stroke (95% CI 1.9%-7.7%). Hyperlipidaemia and severe stenosis of the contralateral ICA were independent risk factors. Twenty-two of 32 patients with a severe stenosis of the contralateral ICA underwent CEA, of which one patient died and three suffered a minor ischaemic stroke. The perioperative risk of CEA in the control group of 20 patients with asymptomatic contralateral ICA occlusion was 0% (0 of 20). CONCLUSIONS: outcome in patients with symptomatic ICA occlusion has not substantially improved over the years. CEA for severe stenosis of the contralateral ICA carried a relatively high risk in our series, but deserves to be studied in a controlled design.     

Risk of stroke for carotid endarterectomy patients with contralateral carotid occlusion

The role of a contralateral carotid occlusion in the appearance of neurological complications after carotid endarterectomy (CEA) operations is a matter of some debate. In the North American Symptomatic Carotid Endarterectomy Trial, the risk of perioperative stroke was found to be higher in patients with a contralateral carotid occlusion. In a literature survey in 2004, however, a significantly increased risk of perioperative stroke was found in only one out of 17 studies on contralateral carotid occlusion patients. We therefore examined the frequency of stroke in patients with contralateral carotid occlusion at our own institution and performed a meta-analysis based on 19 representative studies, including the data from our own institution. Out of 1,960 CEAs at the authors' institute, a significantly higher frequency of 5.6% compared to 2.1% (p = 0.012) for perioperative stroke risk was seen in patients with contralateral carotid occlusion compared to those without. The meta-analysis, based on 19 studies, also showed in 13,438 CEA operations a significantly higher perioperative stroke rate of 3.7% compared to 2.4% (p = 0.002) in the presence of a contralateral carotid occlusion. Nevertheless, due to the extremely poor outcomes of medically treated symptomatic patients, a surgical or endovascular procedure should be sought for these patients. Since the superiority of angioplasty/stent procedures has not yet been verified compared to surgical procedures in these patients, special indication for an endovascular procedure should also be taken into consideration.     

A reassessment of carotid endarterectomy in the face of contralateral carotid occlusion: surgical results in symptomatic and asymptomatic patients

OBJECTIVE: Total occlusion of the contralateral internal carotid artery has often been considered to be a predictor of poor outcome after carotid endarterectomy (CEA) of ipsilateral carotid stenosis. Data from both the North American Symptomatic Carotid Endarterectomy Trial and the Asymptomatic Carotid Atherosclerosis Study have suggested this to be true. However, each of these trials had relatively few patients with contralateral occlusion in the surgical arms of the studies. Recently, advocates of carotid angioplasty and stenting have suggested that this technique may be preferable in patients with a contralateral occlusion because of the perceived poor outcome with surgery. The purpose of this study was to review a large series of CEAs performed in patients with contralateral occlusion to see whether results differed from patients with patent contralateral arteries and to determine whether the presence of preoperative symptoms was an important factor in outcome in these cases. PATIENTS AND METHODS: A review was conducted of a prospectively compiled database of all primary CEAs performed at our institution from 1985 to 1999. Surgery was performed on 2420 patients, of whom 338 (14.0%) had contralateral total occlusion. RESULTS: Patients with contralateral total occlusion were more likely to be symptomatic (65.7% versus 60.1%; P =.1), male (70.9% versus 58%; P <.001), and hypertensive (63.9% versus 58.4%; P =.07) with a positive smoking history (42.6% versus 31.4%; P <.001) than patients with patent contralateral carotid artery. No significant difference was seen in the rates of perioperative neurologic events between patients with contralateral occlusion (3.0%) and those without (2.1%; P =.34). Among the total of 913 asymptomatic patients, of whom 115 had contralateral occlusion, no difference was seen in the rate of perioperative neurologic events (1.8% for contralateral occlusion cases; 1.9% for cases without contralateral occlusion). Among the total of 1507 symptomatic patients, of whom 223 had contralateral occlusion, no significant difference was seen in the rate of perioperative neurologic events (3.7% for contralateral occlusion cases; 2.2% for cases without contralateral occlusion; P =.2). CONCLUSION: The presence of contralateral occlusion does not appear to increase the perioperative risk of CEA. Although the risk of CEA in symptomatic patients with contralateral occlusion may be slightly increased, this must be weighed against the risk with medical treatment alone. CEA can be performed safely in patients with contralateral occlusion, which should not necessarily be considered a high-risk condition for surgery in favor of angioplasty and stenting.     

Evaluation of changes of systemic blood pressure and shunt incidence in CEA.

BACKGROUND: Induced hypertension is widely recommended as a protective measure in carotid endarterectomy (CEA) to prevent shunt insertion. In this study changes of systemic blood pressure were evaluated in relation to the shunt rate when CEA was performed under local anaesthesia. MATERIALS AND METHODS: In 930 CEAs performed for a high-grade (>70%) ICA stenosis under local anaesthesia the mean systemic blood pressure was measured preoperatively (RR1) and directly before carotid cross-clamping (RR2). A ratio was calculated from these values (RRR=RR2/RR1). A shunt was only inserted for clinical signs of cerebral ischemia. If that became necessary later after cross-clamping had been tolerated primarily, the blood pressure during this period was also recorded (RR3). Also the presence of a contralateral ICA occlusion and baseline blood pressure levels were considered as factors with potential impact on shunt necessity. RESULTS: Among the 638 male (69%) and 292 female (31%) patients with a median age of 70 years (ranging from 52 to 91 years) 82 (9%) had a contralateral ICA occlusion. A shunt was used in 177 operations (19%) and significantly more frequent in patients with a contralateral ICA occlusion (39/82=48% vs. 138/848=16%, p<0,001). RRR was significantly reduced in patients who needed a shunt (0.95 (0.41-1.53) vs. 1.0 (0.54-1.9), p=0.002) which was only true for patients with a patent contralateral ICA. The shunt rate did not differ when contrasting RRR thresholds (<0.7 vs. >1.3) or preoperative blood pressure levels (<100 mmHg vs. >120 mmHg) were compared. RRR did not differ between directly or delayed shunted patients. RR3 did not differ significantly from RR2. A regression analysis identified the presence of a contralateral ICA occlusion as the only independent parameter influencing shunt insertion. CONCLUSIONS: Changes in systemic blood pressure during CEA under local anaesthesia seem to influence shunting rather marginally. The value of induced hypertension to prevent cerebral ischemia should be newly discussed.     

Internal carotid artery occlusion: effect of contralateral flow reduction in inducing symptoms

Cerebral ischemic attacks ipsilateral to an occluded internal carotid artery (ICA) continue in more than 16% of patients. With common carotid artery compression on the side of ICA occlusion in 53 patients, the mean (+/- SEM) ophthalmic systolic pressure/brachial systolic pressure (OSP/BSP) ratio fell from 0.58 +/- 0.013 to 0.42 +/- 0.020 (p less than 0.001), without any cerebral ischemic symptoms. Compression of the contralateral patent common carotid artery resulted in the ophthalmic systolic pressure/brachial systolic pressure ratio dropping from 0.67 +/- 0.012 to 0.29 +/- 0.017 (p less than 0.001) on the patient side and from 0.58 +/- 0.013 to 0.48 +/- 0.018 (p less than 0.001). Twenty-six of 53 patients (49%) developed ischemic symptoms in response to compression of the remaining patent ICA system. In contrast, only 8 of 122 patients (6.5%) without ICA occlusion developed any symptoms of cerebral dysfunction (p less than 0.001). This study suggests embolic events rather than flow reduction may be of greater importance in the production of new symptoms and that contralateral flow is critical to normal cerebral function in half the population with ICA occlusion.