Transcervical carotid stenting with internal carotid artery flow reversal: feasibility and preliminary results

OBJECTIVE: Transfemoral carotid artery stenting (CAS), with or without distal protection, is associated with risk for cerebral and peripheral embolism and access site complications. To establish cerebral protection before crossing the carotid lesion and to avert transfemoral access complications, the present study was undertaken to evaluate a transcervical approach for CAS with carotid flow reversal for cerebral protection. METHODS: Fifty patients underwent CAS through a transcervical approach. All patients with symptoms had greater than 60% internal carotid artery (ICA) stenosis, and all patients without symptoms had greater than 80% ICA stenosis. Twenty-one patients (42%) had symptomatic disease or ipsilateral stroke, and 8 patients (16%) had contralateral stroke. Four patients (8%) had recurrent stenosis, 7 patients (14%) had contralateral ICA occlusion, and 1 patient (2%) had undergone previous neck radiation. Twenty-seven procedures (54%) were performed with local anesthesia, and 23 (46%) with general anesthesia. Using a cervical cutdown, flow was reversed in the ICA by occluding the common carotid artery and establishing a carotid-jugular vein fistula. Pre-dilation was selective, and 8-mm to 10-mm self-expanding stents were deployed and post-dilated with 5-mm to 6-mm balloons in all cases. RESULTS: The procedure was technically successful in all patients, without significant residual stenoses. No strokes or deaths occurred. There was 1 wound complication (2%). All patients were discharged within 2 days of surgery. Mean flow reversal time was 21.4 minutes (range, 9-50 minutes). Carotid flow reversal was not tolerated in 2 patients (4%). Early in the experience, carotid flow reversal was not possible in 1 patient, and there were 1 major and 3 minor common carotid artery dissections, which resolved after stent placement. One intraoperative transient ischemic attack (2%) occurred in 1 patient in whom carotid flow was not reversed, and 1 patient with a contralateral ICA occlusion had a contralateral transient ischemic attack. At 1 to 12 months of follow-up, all patients remained asymptomatic, and all but 1 stent remained patent. CONCLUSION: Transcervical CAS with carotid flow reversal is feasible and safe. It can be done with the patient under local anesthesia, averts the complications of the transfemoral approach, and eliminates the increased complexity and cost of cerebral protection devices. Transcervical CAS is feasible when the transfemoral route is impossible or contraindicated, and may be the procedure of choice in a subset of patients in whom carotid stenting is indicated.     

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.     

External carotid endarterectomy with internal carotid artery transposition flap angioplasty for symptomatic internal carotid artery occlusion

The external carotid artery is an important collateral pathway for cerebral perfusion when the internal carotid artery is occluded. After internal carotid artery occlusion, there is a definite risk of ipsilateral neurological events. The authors retrospectively examined their experience with endarterectomy of the external carotid artery for symptomatic internal carotid artery occlusion. Results based on the authors' experience and on historical data show external carotid endarterectomy to be a safe procedure. Obliteration of the cul-de-sac appears to be a very important factor in the prevention of reocclusion or recurrence of symptoms after external carotid endarterectomy. Use of the internal carotid artery stump for patching of the endarterectomized external carotid artery is both safe and effective in treating symptomatic internal carotid artery occlusion.     

Carotid endarterectomy outcome with vein or Dacron graft patch angioplasty and internal carotid artery shortening

OBJECTIVE: This analysis of the outcome of carotid endarterectomy (CEA) was performed during a period of transition from the frequent use of autologous greater saphenous vein grafting to the frequent use of Dacron graft patch reconstruction and from the infrequent use to the moderate use of eversion plication shortening of the endarterectomized internal carotid artery segment. METHODS: From 1990 to 1997, 697 consecutive primary CEAs were performed on 326 men (61 bilateral CEAs) and 272 women (38 bilateral CEAs) with a mean age (+/- SD) of 68 +/- 9 years. The indications were transient ischemic attack in 31% of the patients, stroke or reversible ischemic neurologic deficit in 18%, global ischemia in 12%, and asymptomatic stenosis >/=70% in 39%. Patch reconstruction was performed in the 678 CEAs in which the arteriotomy extended distal to the internal carotid artery bulb (97%; 370 saphenous vein grafts, 308 Dacron grafts). Primary closure was used in the other 19 CEAs. Early in this series, saphenous vein patching frequently was performed, with a gradual transition to the frequent use of knitted Dacron grafts. Concurrent with this, the frequency of the shortening of the internal carotid artery increased from 7% to 40%. Postoperative duplex scans were obtained on 619 CEAs (91%). RESULTS: There were four deaths (0.6%) in 30 days-three from myocardial infarction and one from hyperperfusion stroke. Thirteen strokes (1.9%), nine ipsilateral and four contralateral, occurred in 30 days. Four nonfatal strokes and one death occurred in the saphenous vein group (3.2%), and eight strokes and two deaths occurred in the Dacron graft group (1.4%; P =.16). The combined 30-day stroke or death rate was 2.3% (16/697), and the hospital rate was 1.7% (12/697). Of the three internal carotid artery occlusions, two were identified at 2 months (one Dacron graft, one saphenous vein) and one was identified at 1 year (Dacron graft). Nonocclusive (>/=50%) restenosis was identified in 16 CEAs. Fifteen of these were in the internal carotid artery. The cumulative Kaplan-Meier method of life-table analysis for the >/=50% restenosis rate at 2 months, 6 months, 1 year, and 3 years for Dacron graft patched CEA was 1.7%, 2.3%, 8.8%, and 12.3% and for saphenous vein patched CEA was 0.3%, 0.3%, 0.3%, and 1.1% ( P <.0001). At the same time intervals, the >/=50% restenosis rate for internal carotid artery shortening was 1.0%, 2.5%, 13.7%, and 19.5%, and, when shortening was not done, the rate was 0.8%, 0.8%, 1.1%, and 3.1% (P <.0001). The >/=50% restenosis rate at the same intervals for women was 0.8%, 1.3%, 5.2%, and 8.9%, and, for men, the rate was 0.9%, 0.9%, 1.8%, and 2.5% (P =.11). Univariate analysis of the rate of >/=50% restenosis in 3 years for the 346 vein patched (2; 0.6%) and 186 Dacron graft patched (7; 3.8%) CEAs that did not have internal carotid artery shortening gave a P value of .015. Similarly, Kaplan-Meier method analysis of this subset of nonshortened CEAs gave a higher restenosis rate with Dacron graft patching (P =.012). With multiple logistic regression, the >/=50% restenosis rate was significantly associated with Dacron graft patching (P =.023; odds ratio, 4.5) and internal carotid artery shortening (P =.025; odds ratio, 3.1) and was weakly associated with female gender (P =.15; odds ratio, 2.0). Cox proportional hazards model analysis for >/=50% restenosis gave relative risk ratios of 3.0 (1.6 to 6.8; 95% confidence interval [CI]) for Dacron graft versus vein patching, 2.0 (1.2 to 3.3; 95% CI) for shortening versus not shortening, and 1.5 (0.9 to 2.4; 95% CI) for female versus male gender. CONCLUSION: CEA patching with Dacron grafts and saphenous vein grafts have similar low perioperative thrombosis, stroke, and death rates, although the stroke and death rates were slightly higher but not statistically different when Dacron grafts were used. Dacron graft patched CEAs are more likely to develop >/=50% restenosis than are those that are patched     

Carotid endarterectomy and endovascular angioplasty with stenting in patients with atherosclerotic stenoses and occlusions of the internal carotid artery

The authors made a comparative assessment of carotid endarterectomy and endovascular angioplasty with stenting in patients with atherosclerotic lesions of the carotid arteries. The authors consider that indications to stenting and carotid endarterectomy are identical in patients with stenose and occlusions of the carotid arteries. Contraindications to angioplasty of carotid arteries are determined. It was shown that angioplasty and stenting in atherosclerotic lesions of the carotid arteries was an effective method with a less number of complications as compared with carotid endarterectomy and are thought to be an adequate alternative to open surgical method of treatment of patients with stenoses and occlusions of the carotid arteries.     

Carotid cave aneurysms of the internal carotid artery

In a series of 32 surgical cases of carotid-ophthalmic artery aneurysm, seven of the lesions were located in the "carotid cave." This special type of aneurysm is usually small and projects medially on the anteroposterior view of the angiogram. At surgery, it is located intradurally at the dural penetration of the internal carotid artery (ICA) on the ventromedial side, appears to be buried in the dural pouch (carotid cave), and is often difficult to find, dissect, and clip. The aneurysm extends into the cavernous sinus space, and the parent ICA penetrates the dural ring obliquely. An ipsilateral pterional approach was used in all 32 cases, and ring clips were used exclusively because the aneurysms were located ventromedially. Clipping was successful in five cases. All patients returned to their preoperative occupation, although vision worsened postoperatively in two cases. The technical steps required for successful obliteration of this aneurysm are summarized as follows: 1) exposure of the cervical ICA; 2) unroofing of the optic canal and removal of the anterior clinoid process; 3) exploration of the ICA around the dural ring and opening of the cavernous sinus; 4) direct retraction of the ICA and optic nerve; and 5) application of multiple ring clips to conform to the natural curvature of the carotid artery; a curved-blade ring clip is especially useful. The relevant topographic anatomy is discussed.     

Carotid endarterectomy when the distal internal carotid artery is small or poorly visualized

Purpose: This is a report of the operative findings and results of carotid endarterectomy (CEA) when the conventional arteriogram demonstrates an internal carotid artery with a high-grade origin stenosis and a small or poorly visualized distal extracranial segment with an apparent diameter of 2 mm or less.Methods: Eighteen CEA were performed on 17 patients with this preoperative finding and patent common and external carotid arteries. The indications for CEA were transient ischemia in seven patients, completed minor stroke in five and amaurosis fugax in four patients. One patient had bilateral findings and global cerebral ischemic symptoms.Results: At CEA 16 internal carotid arteries had atherosclerotic very high-grade origin stenosis, and two had chronic occlusion. Ten of the 16 open arteries had true external diameters of 4 mm or more. Of these, seven were normal above the stenosis, two had a long, trailing intraluminal thrombus that was removed, and one had high-grade distal stenosis. Of the six arteries with true diameters of 3 mm or less (hypoplastic), two had a thick fibrotic wall. The carotid stump back pressure for the 16 open internal carotid arteries was 56 ± 15 mm Hg (mean ± SD). This was significantly higher than the 39 ± 14 mm Hg back pressure measured in 1016 arteries without a string sign (p < 0.001). There was one 30-day postoperative death after a stroke. There was no systemic or neurologic morbidity. Post-CEA duplex scans demonstrated eight normal, five mildly stenotic, and five occluded internal carotid arteries. Two of the occlusions were found at CEA and the other three occluded arteries had low flow after CEA, two of which were hypoplastic and the other had a distal stenosis.Conclusions: Patients with symptoms with these findings on arteriograms should undergo CEA. However, the success of CEA in this setting depends on the internal carotid artery anatomy and disease, which is difficult to determine before CEA. Patients with a truly normal extracranial internal carotid artery have an excellent probability of a successful CEA, but this is not the case when the artery is small or fibrotic. Low internal carotid artery flow after a technically satisfactory CEA is a harbinger of thrombosis and should be managed by internal carotid artery ligation and external CEA. (J VASC SURG 1994;19:23-31.)     

Carotid endarterectomy in the awake patient

The advantages of performing carotid endarterectomy in the awake patient have been presented based on a 13 year experience. Anesthesia consisted of either local infiltration of local lidocaine or regional neck block supplemented by intravenous sedation. The principal advantages of the technique are that it is the only exact method of assessing the need for an intraluminal shunt by neurologic assessment of the awake patient during trial carotid cross-clamping, and the elimination of general anesthesia allows carotid endarterectomy to be safely performed on patients with advanced inoperable coronary artery disease and in those with chronic obstructive pulmonary disease. One hundred consecutive carotid endarterectomies have been reported with one late death and one mild, permanent neurologic deficit. These results support the belief that carotid endarterectomy can be performed with very low morbidity and mortality rates by operating on the awake patient.     

Advantages and indications of transcervical carotid artery stenting with carotid flow reversal

AIM: The aim of this Italian prospective registry was to evaluate the applicability and efficacy of the Mo.Ma Device (Invatec, Roncadelle, Italy) for the prevention of cerebral embolization during carotid artery stenting (CAS) in a real world population. METHODS: In 4 Italian centers, 416 patients (300 men; mean age 71.6+/-9 years) between October 2001 and March 2005 were enrolled in a prospective registry. Two-hundred and sixty-four symptomatic (63.46%) with >50% diameter stenosis and 152 (36.54%) asymptomatic patients with >70% diameter stenosis were included. The Mo.Ma Proximal Flow Blockage Embolic Protection System was used to perform protected CAS, achieving cerebral protection by endovascular clamping of the common carotid artery (CCA) and of the external carotid artery (ECA). RESULTS: Technical success, defined as the ability to establish protection with the Mo.Ma device and to deploy the stent, was achieved in 412 cases (99.03%). The mean duration of flow blockage was 4.91+/-1.1 min. Transient intolerances to flow blockage were observed in 24 patients (5.76%), but in all cases the procedure was successfully completed. No peri-procedural strokes and deaths were observed. Complications during hospitalization included 16 minor strokes (3.84%), 3 transient ischemic attacks (0.72%), 2 deaths (0.48%) and 1 major stroke (0.24%). This resulted in a cumulative rate at discharge of 4.56% all strokes and deaths, and of 0.72% major strokes and deaths. All the patients underwent thirty-day follow-up. At thirty-day follow-up, there were no deaths and no minor and major strokes, confirming the overall cumulative 4.56% incidence of all strokes and deaths rate, and of 0.72% rate of major strokes and deaths at follow up. In 245 cases (58.89%) there was macroscopic evidence of debris after filtration of the aspirated blood. CONCLUSIONS: This Italian multicenter registry confirms and further supports the efficacy and applicability of the endovascular clamping concept with proximal flow blockage in a broad patient series. Results match favorably with current available studies on carotid stenting with cerebral protection.     

血管内支架成形术治疗颅外段颈动脉狭窄

目的:分析总结血管内支架治疗颅外段颈动脉狭窄的方法和并发症的预防.方法2001年10月至2008年6月共271例(300侧)颅外段颈动脉狭窄患者接受血管内支架成形术治疗,术前口服氯吡格雷75 ms/d,肠溶阿司匹林100～200 mg/d,辛伐他丁40 mg/晚,共5～10 d.应用肝素持续静脉滴注(50 mg/d)共2 d.术后继续抗血小板、降脂治疗.结果:271例患者(300侧)手术均获成功,颈动脉狭窄和脑缺血症状得到明显改善.术后1周内并发症7例,1例死亡.226例患者3～24个月行超声或数字减影血管造影,5例发生再狭窄;其中45例患者超声随访超过36个月,无再狭窄病例;所有病例随访期间无脑缺血相关症状发生.结论:血管内支架治疗颈动脉狭窄是安全有效的,正确的围手术期的处理以及娴熟的操作技巧是手术成功的关键.     

Current management of the patient with internal carotid artery occlusion

Despite the recent controversy concerning surgical therapy of patients with carotid artery disease, rational therapeutic plans can be developed based on available data. The patient who is symptomatic from occlusion of one or both internal carotid arteries is at particularly high risk for development of stroke and can ill-afford indecision. All symptomatic patients, therefore, with any of the extracranial occlusive disease patterns described are potential surgical candidates. Conversely, among the asymptomatic patients with these same patterns of occlusion, only those with internal carotid occlusion and contralateral stenosis should be considered for surgical therapy. Treatment must be individualised and directed at revascularising stenotic (not occluded) internal carotid arteries, or important collateral vessels such as the external carotid artery and in fewer cases the vertebral artery. The asymptomatic patient with unilateral internal carotid artery occlusion and no contralateral lesions should be monitored closely with Duplex scanning for development of a contralateral stenosis. When a stenosis of 80% or greater is encountered, strong consideration should be given to prophylactic endarterectomy in these patients due to their high risk for stroke. Endarterectomy for a 50-60% stenosis may also be reasonable in a single patent internal carotid artery. In the absence of a significant contralateral stenosis, no treatment is necessary. Individuals with internal carotid artery occlusion and symptoms referable to a contralateral carotid stenosis should also be managed with endarterectomy of the stenotic carotid artery.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of head movements on morphology and flow in the internal carotid artery after carotid angioplasty and stenting versus endarterectomy

OBJECTIVE: Because stents can cause vessel angulation during movement, we hypothesized that internal carotid artery (ICA) stents might lead to alterations of cerebropetal blood flow. This study assessed three-dimensional anatomy and volumetric flow rate (VFR) in the ICA in various head positions by comparing patients treated with carotid angioplasty and stenting (CAS) with patients treated with carotid endarterectomy (CEA). METHODS: Three-dimensional time-of-flight magnetic resonance angiography and magnetic resonance flow quantification were performed on six subjects after CAS (median age, 70 years) and on six subjects after CEA (median age, 67 years). All investigations were performed in five head positions: neutral, bent forward, bent backward, and turned to the treated, ipsilateral side and to the contralateral side. Maximum-intensity projection reconstructions were obtained to measure maximal angulation of the ICA in the forward, backward, ipsilateral, and contralateral positions compared with neutral. Subsequently, the plane perpendicular to the ICA, 1 cm distal to the stent or 4 cm distal to the carotid bifurcation (CEA patients), was established. The VFR through this plane was measured for each position, and the forward, backward, ipsilateral, and contralateral positions were compared with neutral. RESULTS: In CAS patients, there was a median change in ICA angulation of +10.2 degrees (interquartile range, +7.3 degrees to +17.9 degrees ) in the forward position, compared with +0.2 degrees (-1.0 degrees to +2.4 degrees ) in CEA patients ( P = .016). In all other head positions, there was no statistically significant difference in angulation change. There was no statistically significant difference in VFR change between groups in any of the head positions tested. CONCLUSIONS: There was a significant increase in ICA angulation in CAS patients if the head was bent forward; this was not observed in CEA patients. This angulation change did not lead to significant acute changes in cerebropetal blood flow, but it might have chronic effects not yet tested.     

Intracranial internal carotid artery aneurysm associated with extracranial occlusion of the ipsilateral internal carotid artery in a patient with polycystic kidney disease

We report a rare case with polycystic kidney disease (PKD) having an intracranial internal carotid artery aneurysm associated with extracranial occlusion of the ipsilateral internal carotid artery. A 55-year-old man with chronic renal failure due to PKD presented with headache. CT scan and MRI showed no abnormal findings. MRA showed cervical occlusion of the right internal carotid artery and an ipsilateral intracranial carotid aneurysm. At surgery, the saccular aneurysm protruded anterolaterally at the C2 portion of the right internal carotid and was clipped. Hemodynamic stress of the blood flow through the posterior communicating artery and the fragility of arteries because of PKD were considered to be two main causes of aneurysmal formation in this case.     

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.     

Operative balloon angioplasty in the treatment of internal carotid artery fibromuscular dysplasia

Seven patients with symptomatic fibromuscular dysplasia have had eight internal carotid arteries treated by operative balloon dilatation. This technique is described in detail and provides three distinct advantages over conventional graduated intraluminal dilatation--atraumatic passage of the catheter through the affected vessel with fluoroscopic guidance; precise dilatation of the involved segment of the internal carotid artery; and the application of a radial force against the arterial wall rather than a longitudinal shear force, thereby making intimal damage less likely. There were no treatment complications in this group of patients. This technique of balloon angioplasty is compared with the results of treatment in eight patients with fibromuscular dysplasia of the internal carotid artery, who had percutaneous transfemoral angioplasty. Long-term follow-up revealed the resolution of symptoms in all patients.