Prediction of Cerebral Ischemic Tolerance During Carotid Cross-clamping by Angiographic Criteria

OBJECTIVE: To evaluate the prognostic value of angiographic criteria and internal carotid artery (ICA) stump pressure for shunt placement in carotid surgery under local anaesthesia. DESIGN: Prospective clinical trial at a university hospital. MATERIALS AND METHODS: In 120 patients a cerebral angiography was initiated before undergoing carotid surgery. Seventy-five percent of the patients were neurologically asymptomatic, 13% had transient ischaemic attacks and 12% suffered from previous strokes. The operation was exclusively performed under local anaesthesia and prior to cross-clamping the ICA stump-pressure was measured. A shunt was inserted only if hemispheric symptoms or unconsciousness occurred independent of the angiographic findings or stump pressure. RESULTS: In 23% (27/120) a shunt became necessary and significantly (p<0.001) more often when there was a cross-flow towards the contralateral hemisphere (12/20=60%) or if the contralateral ICA was occluded (9/13=69%). The sensitivity for not needing a shunt in case of cross-flow towards the side of operation was 91% (52/57) whereas the specificity was 35% (22/63). ICA stump-pressure was significantly reduced in patients requiring a shunt (31 mmHg) compared to those not needing a shunt (53 mmHg) (p<0.001), but no definitive threshold value was found determining the need for shunting. Intraoperatively, no persistent neurological complication developed. CONCLUSIONS: Angiographic cross-flow was a good, but not perfect predictor for the need of an intraoperative shunt.     

External carotid endarterectomy: indications, technique, and late results

In the past 14 years, 22 patients (25 operated sides), with occlusion of the internal carotid artery (ICA), underwent ipsilateral external carotid artery (ECA) endarterectomy at our institution. Operative indications were amaurosis fugax in 13 sides and nonlateralizing transient ischemic attacks in the remaining 12. There were no operative deaths. One patient suffered a minor stroke after operation. Follow-up ranged from 6 to 110 months (median 36 months). In 16 cases, simple endarterectomy with or without vein patch closure was performed (type I). In two cases the ostium of the ICA was occluded with interrupted sutures after endarterectomy (type II). In the remaining seven cases the ICA was transposed as a patch over the endarterectomized ECA after endarterectomy (type III). All but six patients (six sides) underwent duplex scanning or angiography during follow-up. Four of nine patients with previous nonlateralizing symptoms had persistent symptoms after operation, whereas none of those with previous amaurosis fugax did. Recurrent occlusive disease was more common in type I reconstructions (p less than 0.05). Proper ECA reconstruction results in long-term patency. In the patient with ipsilateral ICA occlusion, transposition of the ICA as a patch over the endarterectomized ECA offers a valid hemodynamic solution. Objective parameters are needed to identify patients with nonlateralizing symptoms who will benefit from operation.     

症状性颈内动脉闭塞的术前评估及手术治疗

目的:探讨症状性颈内动脉(ICA)闭塞患者手术治疗的效果和术前评价方法。方法:选择海南省人民医院血管外科2010年1月—2016年3月手术治疗的11例ICA闭塞的患者,2例行颈动脉内膜剥脱术(CEA),9例行CEA加取栓术。术前均行头颈联合CTA和颈部血管彩超,部分患者行脑CT灌注成像、经颅彩色多普勒超声以及脑血管造影等检查,观察患者围术期与长期疗效。结果:所有患者ICA闭塞均为单侧,其中4例对侧ICA有50%的狭窄。闭塞主要位于ICA起始端,8例闭塞段延至颅底,闭塞长度16~85 mm。术前颈动脉彩超均在可在颅底探及ICA血流。10例手术再通成功,1例失败。术后10例脑缺血症状明显改善,其中3例出现过度灌注综合征。随访期,1例患者ICA在术后3个月闭塞。1例在术后18个月死亡。结论:手术治疗ICA闭塞具有满意安全的围手术期效果和较好的中远期效果。术前精确的评估是手术成功的关键。     

Stellenwert der Revaskularisation eines akuten Karotisverschlusses

BACKGROUND AND PURPOSE: We examined indications for emergent revascularisation of acutely occluded internal carotid artery (ICA) using current diagnostic methods. MATERIAL AND METHODS: From 1997 to 2006 we prospectively followed 34 consecutive patients undergoing emergency revascularisation due to acute extracranial ICA occlusion and acute ischaemic stroke within 72 h after symptom onset (mean 25) and within 36 h after admission (mean 16). Exclusion criteria were occlusion of the intracranial ICA or ipsilateral middle cerebral artery (MCA), ischaemic infarction of more than one third of the MCA perfusion area, or reduced level of consciousness. All patients underwent duplex sonography, cerebral CT, and/or MRI and angiography (MRA and/or DSA). We performed endarterectomy and thrombectomy of the ICA. RESULTS: Confirmed by postoperative duplex sonography at discharge, ICA revascularisation was successful in 30 (88%) of 34 cases. Postoperative intracranial haemorrhage was detected in two patients (6%) and perioperative reinfarction in one (3%). Compared to the preoperative status, 20 patients (59%) showed signs of clinical improvement by at least one point on the Rankin scale, ten patients (29%) remained stable, and two patients (6%) had deteriorated. The 30-day mortality was 6% (two patients). CONCLUSION: After careful diagnostic workup, revascularisation of acute extracranial ICA occlusion is feasible with low morbidity and mortality.     

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.     

Transcranial Doppler for detection of cerebral ischaemia during carotid endarterectomy.

We evaluated transcranial Doppler sonography (TCD) for the detection of cerebral ischaemia during carotid endarterectomy in 30 male and 14 female patients with ipsilateral focal cerebro-vascular symptoms. Surgery was performed during halothane-nitrous oxide anaesthesia with moderate hypocapnia. Eight patients had a temporary shunt owing to contralateral occlusion or a stump pressure below 40 mmHg, and/or EEG flattening. Transcranial Doppler sonography was followed intra-operatively together with electro-encephalography (EEG), internal carotid artery (ICA) pressures and cerebral blood flow (CBF). Middle cerebral artery mean flow velocity (Vmean) was 38 (22-96) cm s-1 (median and range) and decreased during cross-clamping to 28 (10-60) cm s-1 (p less than 0.0001). After removal of the clamp it increased to 42 (20-102) cm s-1 (p less than 0.0001). AVmean clamp of less than 30 cm s-1 together with a Vmean clamp: Vmean pre-clamp ratio of less than 0.6 showed an accuracy with respect to CBF below 20 ml 100 g-1 min-1 of 89%. AVmeanclamp:Vmean pre-clamp ratio below 0.4 detected all all patients with EEG flattening (n = 3) (accuracy 97%). The corresponding level of accuracy obtained with stump pressure was 80%. The results indicate that middle cerebral flow velocity enables an increase in the accuracy of detecting cerebral ischaemia during carotid endarterectomy.     

Management of internal carotid artery occlusion

Although attempts to restore patency of occluded internal carotid arteries are now rarely made, endarterectomy in the contralateral artery, external carotid endarterectomy and until recently EC/IC bypass have remained surgical options in the management of such patients. Over a four-year period at this institution 104 patients underwent carotid endarterectomy for stenosis. In this group the contralateral carotid was patent (Group A). Fifty-four patients with unilateral carotid artery occlusion underwent contralateral endarterectomy (Group B), 8 underwent ECA/ICA bypass (Group C) and 4 an ECA endarterectomy (Group D). No statistically significant difference was noted in perioperative stroke and death rates for Groups A and B were (1% and 1%) and (3.7% and 1.9%) respectively. One Group C patient died from perioperative stroke (12.5%). For late events the life table adjusted annual rates for stroke and mortality were similar, Group A (stroke 2.1% and death 5%), and Group B (stroke 1.6% and death 5%). In Group C stroke rate was 10% and death 3%. All four patients undergoing ECA endarterectomy were relieved of their symptoms. It is concluded that in patients with internal carotid artery occlusion TEA may be performed with perioperative morbidity and mortality rates comparable to those when the opposite carotid artery is patent. The late outcome for stroke compares favorably with the reported natural history of the disease and outcome for such patients treated medically in the Joint Study of Extracranial Occlusion and EC-IC Bypass Study. External carotid artery endarterectomy appears useful in the treatment of embolic events on the occluded side. ECA/ICA bypass does not appear to confer benefit.     

The value and limitations of magnetic resonance angiography of the circle of Willis in patients undergoing carotid endarterectomy

Magnetic resonance angiography is a useful technique to determine the patency of the circle of Willis when compared with conventional four-vessel angiography. The purpose of this study is to determine whether the integrity of the circle of Willis, assessed by magnetic resonance angiography, provides adequate collateral cerebral circulation during carotid endarterectomy and correlates with internal carotid artery back pressure. Over a recent 20-month period, 35 patients were studied preoperatively with magnetic resonance angiography of the carotid bifurcations of the circle of Willis and the vertebrobasilar system. All patients underwent standard carotid endarterectomy with intraoperative measurement of internal carotid artery back pressure. Patients with an internal carotid artery back pressure < 50 mmHg had an intraluminal shunt placed. Deficiencies in branches of the circle of Willis, the carotid bifurcation and the vertebrobasilar system determined by magnetic resonance angiography were correlated with internal carotid artery back pressure using Fisher's exact test. Only one patient had a completely intact circle of Willis. Eleven of 16 patients (69%) who had an internal carotid artery back pressure < 50 mmHg had an occluded A1 segment of the anterior cerebral artery combined with an occluded posterior communicating artery, whereas only five of 19 patients (26%) who had an internal carotid artery back pressure > 50 mmHg had similar findings (P < 0.03). Severity of occlusive disease of the contralateral internal carotid artery and the basilar artery did not independently predict internal carotid artery back pressure. An occluded anterior branch of the circle of Willis in combination with an occluded posterior branch of the circle of Willis is associated with an internal carotid artery back pressure < 50 mmHg. Although magnetic resonance angiography of the circle of Willis may provide valuable anatomic information, it is not sufficiently accurate to predict the need for carotid shunting and therefore its use cannot be justified on a routine basis.     

Cerebrovascular reactivity before and after carotid endarterectomy

BACKGROUND: The hemodynamic relevance of internal carotid artery (ICA) stenosis often does not correlate with anatomic features, as angiographically defined. The cerebrovascular reactivity (CVR) has been advocated as a means of defining the cerebral hemodynamic impairment. METHODS: We assessed the results of pre- and postoperative CVR evaluation, using the CO2 transcranial doppler method, in 25 patients with high-grade ICA stenosis. The patients with history of stroke, evidence of cerebral CT infarction or symptoms from the contralateral circulation or the brain stem were excluded to avoid the effects of cerebral infarction on the hemodynamic studies. Statistical analysis was used to evaluate the CVR changes after carotid endarterectomy. RESULTS: Preoperative evaluation showed that CVR was generally well correlated with the degree of ICA stenosis and concomitant contralateral carotid steno-occlusion. Before endarterectomy the mean CVR value was 66.5% (moderately reduced). After surgery the overall mean value of CVR was 84.1% (normal), with a statistically significant improvement. CONCLUSION: The results of this study suggest that the CVR evaluation allows one to obtain hemodynamic information of clinical interest in the patients with ICA stenosis and that carotid endarterectomy is effective to restore the CVR in patients with cerebral hemodynamic impairment.     

External carotid artery reconstruction: its role in the treatment of cerebral ischemia

Twenty-one patients who underwent 22 external carotid artery reconstructions for cerebral ischemia were reviewed. Ten patients had amaurosis fugax, 9 had hemispheric ischemia, and 2 were asymptomatic. With the exception of one patient, all had ipsilateral internal carotid artery occlusion and either external carotid stenosis or a cul-de-sac of the occluded internal carotid artery. Six patients had ipsilateral common carotid occlusions. The operative technique has been presented. There were no operative strokes or new neurologic deficits. All patients were relieved of symptoms. Patients were followed a mean of 32 months. During follow-up, 3 ipsilateral transient ischemic attacks occurred during the first 3 months. Four strokes occurred (one ipsilateral and three contralateral) from 4 to 33 months postoperatively. Ipsilateral stroke rate by life table analysis was 1 percent per year. These data suggest that external carotid artery reconstruction is a safe, effective, and durable therapeutic alternative for management of patients with cerebral ischemia and an ipsilateral occluded internal carotid artery. External carotid endarterectomy eliminates a potential source of emboli and increases cerebral perfusion. Because of the increase in cerebral blood flow, subsequent extracranial-to-intracranial bypass may be unnecessary.     

Surgical therapy for recent total occlusion of the internal carotid artery

From January 1980 until May 1983, 24 patients had surgical exploration of the carotid bifurcation for suspected recent total occlusion of the internal carotid artery (ICA). All patients had recent onset of neurologic symptoms related to the ipsilateral cerebral hemisphere. Selective carotid angiography determined preoperative total occlusion of the ICA. Because surgery failed to reopen the ICA in nine patients, they had endarterectomy of the external carotid artery. Fifteen patients had initially successful thromboendarterectomy of the ICA. Prior to patient dismissal, patency was documented by B-mode ultrasound or digital subtraction angiography (DSA). All 15 patients had another B-mode ultrasound scan or DSA at least 45 days after thromboendarterectomy. On reexamination four ICAs were reoccluded, but only one patient became symptomatic. There were no operative deaths and no increase in preoperative neurologic deficits. The natural history of patients with total occlusion of the ICA is variable. The most important factor influencing a therapeutic decision is the patient's neurologic status. This study supports an aggressive, early surgical intervention for recent total occlusion in carefully selected patients.     

Shaking limb transient ischemic attacks: unusual presentation of carotid artery occlusive disease: report of two cases

OBJECTIVE AND IMPORTANCE: Shaking limb transient ischemic attacks (TIAs) represent a rare clinical syndrome that has been ascribed to focal cerebral ischemia attributable to insufficient brain perfusion, usually resulting from carotid artery occlusive disease. The techniques conventionally used to evaluate this condition are contrast angiography, carotid artery ultrasonography, and magnetic resonance angiography. Treatment consists of internal carotid artery (ICA) endarterectomy or, in the case of complete ICA occlusion, extracranial-intracranial bypass. In this report, two patients with shaking limb TIAs are presented. For one patient, preoperative evaluations included single-photon emission computed tomographic studies with acetazolamide vasodilator challenge; for the second patient, computed tomographic angiography was used to assess vascular anatomic features. CLINICAL PRESENTATION: Two patients with severe carotid artery disease presented with brief, recurrent, shaking limb TIAs. Angiograms obtained for Patient 1 demonstrated complete ICA occlusion in association with severe external carotid artery stenosis, whereas preoperative single-photon emission computed tomographic scans revealed a lack of cerebrovascular reserve in response to acetazolamide challenge. Carotid artery duplex ultrasonography and computed tomographic angiography demonstrated severe stenosis of the ICA for Patient 2. INTERVENTION: Patient 1 underwent a left external carotid artery endarterectomy. Patient 2 underwent a right ICA endarterectomy. CONCLUSION: After surgery, the shaking limb episodes ceased for both patients. Postoperative single-photon emission computed tomographic scans for Patient 1 demonstrated increased cerebral blood flow in response to acetazolamide challenge. These data provide support for the concept that shaking limb TIAs are related to hemodynamic failure and that improvements in cerebral blood flow through conducting vessels can alleviate the condition.     

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.     

External carotid artery revascularization: indications, operative techniques and results.

The external carotid artery (ECA) is an important collateral pathway in patients with ipsilateral internal carotid artery (ICA) occlusion and recurrent symptoms. An ipsilateral ECA revascularization can improve cerebral perfusion or eliminate an embolic source. In the past 11 years 11 patients underwent operation, 6 times for amaurosis fugax and 5 times for transient ischaemic attacks. Eight times ECA endarterectomy was performed for stenosis and/or ulceration. Eight times closure or separation of the ICA stump with thrombus was carried out. There were no perioperative neurological deficits or deaths, with the exception of 3 patients who already had a long-standing deficit due to the ICA occlusion. All patients were relieved of their ocular or hemispheric symptoms in a follow-up period of 8 years. Two late strokes occurred after 1 1/4 and 4 years. Ipsilateral ECA revascularization is an effective and safe operation and has good long-term results.     

Cerebral hyperperfusion syndrome after carotid endarterectomy: predictive factors and hemodynamic changes

PURPOSE: It is believed that cerebral hyperperfusion syndrome (CHS) is caused by loss of cerebral autoregulation resulting from chronic cerebral ischemia and that factors including increased intraoperative cerebral blood flow, ipsilateral or contralateral carotid disease, and postoperative hypertension may cause CHS. We describe our experience with CHS, which diverges from published reports. MATERIALS AND METHODS: From March 2000 to February 2002 we performed 455 carotid endarterectomy (CEA) procedures in 404 patients at our institution. CHS developed 1 to 8 days (mean, 3.2 +/- 2.5 days) postoperatively in 9 patients (2%), 6 women and 3 men, whose age ranged from 52 to 84 years (mean, 69 +/- 8 years). Indications for surgery in 8 patients without neurologic symptoms were ipsilateral internal carotid artery (ICA) stenoses ranging from 70% to 99% (mean, 80% +/- 7%); the remaining patient had an ipsilateral stroke, with good clinical recovery, 7 weeks before CEA. Only 1 patient had significant contralateral ICA stenosis (70%). However, 5 patients had undergone contralateral CEA within the previous 3 months. CHS symptoms were severe headache in 5 patients, seizures in 3 patients (1 stroke), and visual disturbance and ataxia in 1 patient. All 404 patients (455 cases) underwent intraoperative and early (2 weeks) postoperative carotid artery duplex scanning. The 9 patients with CHS also underwent carotid artery duplex scanning at the time of the neurologic event. RESULTS: Mean intraoperative ICA volume flow (MICAVF) in the 9 CHS cases was not significantly different from that in the other 446 cases (170 +/- 47 mL/min and 182 +/- 81 mL/min, respectively). However, mean ICA volume flow (481 +/- 106 mL/min) and peak systolic velocity (PSV) (108 +/- 33 cm/s) for the 9 CHS cases measured at onset of symptoms were higher than those for the remaining 446 cases (267 +/- 87 mL/min and 80 +/- 26 cm/s, respectively) (P <.01). Of the 9 patients with CHS, only 3 had systolic blood pressures more than 160 mm Hg at onset of symptoms. Severity of ipsilateral and contralateral ICA stenoses was not significantly different between the 9 CHS cases and the remaining 446 cases. CONCLUSIONS: These data do not corroborate the common belief that CHS occurs preferentially in patients with severe ipsilateral or contralateral carotid disease, increased intraoperative cerebral perfusion, or severe hypertension. Recently performed contralateral CEA (<3 months) appears to be predictive of CHS.     

Stump pressure, the contralateral carotid artery, and electroencephalographic changes

Electroencephalographic (EEG) monitoring and measurement of stump pressure are the most widely employed methods of assessing the risk of cerebral ischemia during carotid endarterectomy. The status of the contralateral carotid artery has also been thought to influence the need for placing a shunt. The relationship of EEG monitoring, stump pressure, and the contralateral carotid artery has not been completely delineated. We retrospectively reviewed these three variables in 113 patients undergoing 124 carotid endarterectomies. The contralateral artery was classified as occluded, stenotic (greater than 50% decrease in diameter), or nonstenotic. There was a 48% incidence of EEG changes with contralateral occlusion, 18% with stenosis, and 21% with nonstenotic arteries (p = 0.014). There was a 73% incidence of EEG changes when the stump pressure was less than 25 mm Hg, 32% when the stump pressure was 25 to 50 mm Hg, and 2% when the stump pressure was greater than 50 mm Hg (p less than 0.001). There was no significant difference in the mean stump pressure for patients with occlusion (43.8 mm Hg), stenosis (44.7 mm Hg), or nonstenotic contralateral arteries (51.3 mm Hg). All patients with contralateral occlusion and a stump pressure less than 25 mm Hg had EEG changes. No patient with a stump pressure greater than 50 mm Hg and a patent contralateral artery had EEG changes. Although the incidence of EEG changes in the majority of patients was not accurately predicted by the stump pressure and the status of the contralateral carotid artery, stump pressure less than or equal to 50 mm Hg was sensitive, identifying 97% of patients with EEG changes.     

Carotid occlusive disease presenting with loss of consciousness

The authors report 9 patients who presented with loss of consciousness (syncope) due to occlusive carotid artery diseases. All patients were males, and their age ranged from 59 to 83 years. The attack was associated with dehydration or hypotension in 5 patients. MRI demonstrated fresh cerebral infarction in the watershed zone. Cerebral angiography revealed occlusion of the unilateral internal carotid artery (ICA) in 7 patients, severe stenosis of the bilateral ICA in one, and occlusion of the unilateral ICA and severe stenosis of the contralateral ICA in one. Single photon emission tomography (SPECT) or positron emission tomography (PET) suggested reduced cerebral perfusion reserve because of inappropriate development of collateral circulation in 4 out of 9 patients. These 4 patients underwent superficial temporal artery to middle cerebral artery anastomosis and/or carotid endarterectomy. Other 5 patients were medically treated. No further episode of syncope occurred in all 9 patients during follow-up periods. The results suggest that occlusive carotid artery diseases should be taken in considerations as a cause of syncope attack.     

Direct and primary carotid endarterectomy for common carotid artery occlusion. Report of 2 cases

BACKGROUND: Cerebral ischemia associated with chronic CCA occlusion is a rare condition and raises strategic dilemma when the revascularization is needed. METHODS: Two patients with CCA occlusion presented with ischemic symptom associated with the affected side. Both patients underwent vascular reconstruction by direct carotid endarterectomy to achieve primary restoration of CCA to ICA flow. RESULTS: Successful reopening of the vessels was obtained in both patients without the evidence of postsurgical ischemic event. Follow-up MRA was obtained at later than 6 months after surgery, which demonstrated patent CCA-ICA in both patients. CONCLUSIONS: Direct carotid endarterectomy of the occluded CCA can be safely performed if the preoperative angiography suggest still patent vessels distal to carotid bifurcation and the substantial "back flow" is obtained from ICA during arteriotomy.     

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.     

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.