Prosthetic bypass for restenosis after endarterectomy or stenting of the carotid artery

Objective

The objective of this study was to evaluate the results of prosthetic carotid bypass (PCB) with polytetrafluoroethylene (PTFE) grafts as an alternative to carotid endarterectomy (CEA) in treatment of restenosis after CEA or carotid artery stenting (CAS).

Prosthetic Carotid Bypass Grafts for Atherosclerotic Lesions: A Prospective Study of 198 Consecutive Cases

ObjectivesCarotid endarterectomy (CEA) is the standard treatment for atherosclerotic lesions involving the carotid bifurcation. However, CEA can be challenging under some conditions. The goal of this study was to determine the outcome and durability of prosthetic carotid bypass grafting (PCB) with polytetrafluoroethylene (PTFE) grafts as an alternative to CEA.MethodsThis is a prospective series of 198 consecutive patients with PCB, representing 12.4% of 1595 patients with a carotid reconstruction procedure performed in our department between September 1986 and December 2006. Qualifying event was stroke in 67 patients (34%) and transient ischaemic attack (TIA) in 45 (23%), and 86 patients (43%) were asymptomatic. Primary indications for PCB were extensive atherosclerotic lesions (n = 71; 36%), carotid stenosis associated with kinking (n = 49; 25%), recurrent stenosis (n = 47; 23%), stenosis after radiation therapy (n = 18; 9%) and technical failure of CEA (n = 13; 7%), with excessive arterial wall thinning and perforation after endarterectomy (n = 10) or intimal flap on completion digital angiography (n = 3).ResultsThe combined stroke and death rate at 30 days were 0.5% (one stroke). Median follow-up was 9.5 years (interquartile range (IQR): 6.2–18.3 years). At 10 years, primary patency was 97.9 ± 3.4%. Six PCBs (3.0%) became occluded during follow-up; one patient had a restenosis greater than 50% and 18 patients (9.1%) had a restenosis of less than 50%. Five patients had an ipsilateral stroke (one postoperative stroke, one at 103 days with a patent PCB and three related to occlusion of the PCB at 4, 13 and 15 years after the procedure). At 10 years, cumulative stroke-free survival was 98.4 ± 3.2%, and cumulative survival was 78.8 ± 7.0%.ConclusionsPCB is a safe surgical alternative and is durable, with a low incidence of graft restenosis, when CEA seems hazardous.     

Outcome of carotid stent-assisted angioplasty versus open surgical repair of recurrent carotid stenosis

PURPOSE: We compared outcome and durability of carotid stent-assisted angioplasty (CAS) with open surgical repair (ie, repeat carotid endarterectomy [CEA]) to treat recurrent carotid stenosis (RCS). METHODS: A retrospective review of anatomic and neurologic outcomes was carried out after 27 repeat CEA procedures (1993-2002) and 52 CAS procedures (1997-2002) performed to treat high-grade internal carotid artery (ICA) RCS after CEA. The incidence of intervention because of symptomatic RCS was similar (repeat CEA, 63%; CAS, 60%), but the interval from primary CEA to repeat intervention was greater (P <.05) in the repeat CEA group (83 +/- 15 months) compared with the CAS group (50 +/- 8 months). In the CAS group, 17 of 52 arteries (33%) were judged not to be surgical candidates because of surgically inaccessible high lesions (n = 8), medical comorbid conditions (n = 4), neck irradiation (n = 3), or previous surgery with cranial nerve deficit or stroke (n = 2). Three patients who underwent repeat CEA had lesions not appropriate for treatment with CAS. RESULTS: Overall 30-day morbidity was similar after CAS (12%; death due to ipsilateral intracranial hemorrhage, 1; nondisabling stroke, 1; reversible neurologic deficits or transient ischemic attack, 2; access site complication, 2). and repeat CEA (11%; no death; nondisabling stroke, 1; reversible cranial nerve injury, 1; cervical hematoma, 1). Combined stroke and death rate was 3.7% for repeat CEA and 5.7% for CAS (P >.1). All duplex ultrasound scans obtained within 3 months after CEA and CAS demonstrated patent ICA and velocity spectra of less than 50% stenosis. During follow-up, no repeat CEA (mean, 39 months) or CAS (mean, 26 months) repair demonstrated ICA occlusion, but two patients (8%) who underwent repeat CEA and 4 patients (8%) who underwent CAS required balloon or stent angioplasty because of 80% RCS. At last follow-up, no patient had ipsilateral stroke and all ICA remain patent. At duplex scanning, stenosis-free (<50% diameter reduction) ICA patency at 36 months was 75% after repeat CEA and 57% after CAS (P =.26, log-rank test). CONCLUSIONS: Carotid angioplasty for treatment of high-grade stenotic ICA after CEA resulted in similar anatomic and neurologic outcomes compared with open surgical repair. Most lesions are amenable to endovascular therapy, and CAS enabled treatment in patients judged not to be suitable surgical candidates. Duplex scanning surveillance after repeat CEA or CAS is recommended, because stenosis can recur after either secondary procedure.     

Early and late outcomes of young patients after carotid endarterectomy.

BACKGROUND AND PURPOSE: Carotid atherosclerotic disease in young adults is uncommon but may be more virulent and diffuse than in older patients. Although few studies have well established that carotid endarterectomy (CEA) is of benefit for high-grade asymptomatic lesions and for moderate- and high-grade symptomatic lesions, the safety and durability of CEA in the young remain controversial. The aim of this study was to compare CEA outcome in young people with outcome in an older control group. METHODS: Thirty-five patients up to 50 years old (mean 46.5 +/- 0.5 years) and undergoing 42 CEAs were compared with a randomly selected group of 50 patients more than 60 years old (mean 68.7 +/- 0.4 years) and undergoing 55 CEAs during the same period. Data were obtained on demographics, atherosclerotic risk factors, indications for surgery, perioperative outcome, recurrent stenosis and symptoms, late stroke, and survival. RESULTS: Smoking (P < .001), alcohol consumption (P < .001), and lower levels of high-density lipoprotein cholesterol (P = .02) were more prevalent in the young patients, who were also more likely to be symptomatic at presentation (P < .001) with a higher incidence of stroke (P = .01) and contralateral carotid occlusion (P = .04). The perioperative stroke risk and mortality rates were nil for the young group. During a mean follow-up of 47 +/- 40 months, there were no significant differences between the 2 groups in survival, symptom recurrence, stenosis recurrence, and reoperation rates. Young patients had a higher incidence of contralateral disease requiring surgery (P = .04). CONCLUSIONS: These findings show that CEA may be performed in young adults with an excellent perioperative outcome; recurrence, late stroke, and survival rates do not differ significantly from those observed among their older counterparts.     

Asymptomatic carotid stenosis and unrelated operations: should we be more aggressive?

BACKGROUND: Carotid lesions will often remain asymptomatic during the perioperative period, so prophylactic carotid endarterectomy (CEA) has not been advocated before other operations. The purpose of this study was to characterize the clinical manifestations of new neurologic symptoms occurring in patients with previously asymptomatic carotid occlusive disease who have undergone recent operations. STUDY DESIGN: We performed a retrospective review of patients developing neurologic symptoms attributable to carotid occlusive disease after unrelated operations. RESULTS: Eleven patients (mean age 68+/-6.4 years, 8 men, 3 women) developed new neurologic symptoms from previously asymptomatic extracranial carotid stenoses after 11 unrelated procedures. Neurologic events included hemispheric stroke (n = 10) and amaurosis fugax (n = 1). Two intraoperative strokes occurred (one mastectomy, one prostatectomy). Other events occurred a mean of 5.8+/-5 (range 1 to 16) days after aortic surgery (n = 2), infrainguinal bypass (n = 3), contralateral CEA for symptomatic disease (n = 2), incisional herniorrhaphy (n = 1), and prostate surgery (n = 1). Responsible internal carotid artery lesions were all stenoses greater than 80%; seven were clearly greater than 90%. Those suffering intraoperative stroke or stroke within 24 hours of operation (n = 3) were not receiving antithrombotic therapy. All other events (n = 8) occurred despite the use ofantiplatelet or anticoagulant agents. Four underwent emergent CEA. Four had elective CEA performed after reaching a neurological recovery plateau. CONCLUSIONS: Critical, asymptomatic internal carotid artery stenoses may cause neurologic symptoms after unrelated surgical procedures.     

Carotid stent-assisted angioplasty: the newest addition to the surgeons' armamentarium in the management of carotid occlusive disease

Carotid artery angioplasty and stenting (CAS) has been accomplished in multiple centers with short-term and midterm results similar to carotid endarterectomy (CEA). Until completion of multicentered prospective evaluation of the benefit of CAS versus established therapy (CEA) clinical judgment must be used to determine whether an individual patient with unusual technical challenges and/or risks might be best suited for CEA or CAS. We report our experience with 41 CAS procedures in 39 patients treated from November 1996 through November 2001. Six patients had primary lesions (three symptomatic and three asymptomatic). Thirty-three patients had 35 procedures for recurrent carotid stenosis (11 symptomatic and 24 asymptomatic). Technical success was achieved in 40 of 41 procedures. No deaths occurred. The 30-day major stroke rate was one in 41 (2.4%), and the overall 30-day stroke/transient ischemic attack rate was three in 41 (7.3%). No recurrence or late neurologic events were seen in patients treated for primary carotid stenosis. A 23 per cent recurrence rate was observed in patients treated for recurrent carotid stenosis, after one or more CEAs, with mean follow-up of 18 +/- 14 months. Recurrence requiring operative correction with carotid resection and interposition grafts occurred in three patients treated with CAS in this group. Late deaths occurred in six patients; one of these was due to stroke. Overall freedom from late stroke and/or need for reintervention (by Kaplan-Meier analysis) was 64 +/- 13 per cent at 48 months in the group treated by CAS for post-CEA recurrence. CAS represents a technically simplistic means of providing carotid revascularization. However, its role remains undefined and benefits unproven. Surgical revascularization remains appropriate for patients with operable carotid lesions. However, surgical revascularization is not always an ideal option when we are faced with difficult carotid lesions and risks. For this reason we advocate that all surgeons who intend to remain specialists in the management of carotid disease should attain, master, and maintain the skills necessary for CAS.     

Strategies for preventing stroke after coronary artery bypass grafting

To evaluate the usefulness of our strategy for preventing stroke after CABG, 343 consecutive patients were investigated retrospectively. Patient ages ranged from 32 to 31 years (mean; 63 ± 9 years). There were 254 males and 59 females. Number of grafts per patient was 1 to 5 (mean 2.4 ± 0.9 grafts). In 193 patients, internal carotid arteries (ICAs) were preoperatively evaluated by duplex scanning or cerebral angiogram. The degree of atherosclerosis in the ascending aorta was preoperatively examined by plain computed tomography in 181 patients, during surgery by ultrasonography in 75 patients and palpation in all patients. Results: 1. On preoperative examination, there were 26 patients (15.1%) with ICA stenosis greater than 50% and 15 patients (7.8%) with stenosis greater than 75%. Six patients had bilateral ICA stenosis or occlusion greater than 75%. In 26 patients with ICA stenosis greater than 50%, history of stroke was significantly more prevalent than that in 167 patients without ICA stenosis (12 patients: 46.2% vs 22 patients: 13.1%, p<0.001). In patients with ICA stenosis greater than 75%, 6 patients were symptomatic and 8 were asymptomatic. For these patients, concomitant carotid endarterectomy and CABG were performed in 5, two stage procedures in 7 reconstruction of cerebral perfusion followed by CABG; 4, followed by CEA: 3), and CABG alone in 3. There was no stroke in any of these patients. 2. Atherosclerosis of the ascending aorta was found in 69 of 343 patients (20.1%). In these patients, single clamp technique was applied in 50 patients, aortic no touch technique in 12 and CABG without cardiopulmonary bypass in one. The arterial cannulation site was changed to femoral artery in 15 and to axillary artery in 6 patients. Statistical analysis indicated that age (older than 60 years) and history of stroke were significant risk factors for atherosclerotic ascending aorta. 3. There were 3 patients (0.9%) with perioperative stroke caused by embolism from the ascending aorta in one and hypoperfusion of the brain during cardiopulmonary bypass in two. Conclusion: Proper treatment of atherosclerotic ascending aorta and carotid occlusion may reduce the incidence of stroke in CABG patients.     

Reoperation for carotid stenosis is as safe as primary carotid endarterectomy.

PURPOSE: Patients with recurrent carotid artery stenosis are sometimes referred for carotid angioplasty and stenting because of reports that carotid reoperation has a higher complication rate than primary carotid endarterectomy. The purpose of this study was to determine whether a difference exists between outcomes of primary carotid endarterectomy and reoperative carotid surgery. METHODS: Medical records were reviewed for all carotid operations performed from September 1993 through March 1998 by vascular surgery faculty at a single academic center. The results of primary carotid endarterectomy and operation for recurrent carotid stenosis were compared. RESULTS: A total of 390 operations were performed on 352 patients. Indications for primary carotid endarterectomy (n = 350) were asymptomatic high-grade stenosis in 42% of the cases, amaurosis fugax and transient ischemic symptoms in 35%, global symptoms in 14%, and previous stroke in 9%. Indications for reoperative carotid surgery (n = 40) were symptomatic recurrent lesions in 50% of the cases and progressive high-grade asymptomatic stenoses in 50%. The results of primary carotid endarterectomy were no postoperative deaths, an overall stroke rate of 1.1% (three postoperative strokes, one preoperative stroke after angiography), and no permanent cranial nerve deficits. The results of operations for recurrent carotid stenosis were no postoperative deaths, no postoperative strokes, and no permanent cranial nerve deficits. In the primary carotid endarterectomy group, the mean hospital length of stay was 2.6 +/- 1. 1 days and the mean hospital cost was $9700. In the reoperative group, the mean length of stay was 2.6 +/- 1.5 days and the mean cost was $13,700. The higher cost of redo surgery is accounted for by a higher preoperative cerebral angiography rate (90%) in redo cases as compared with primary endarterectomy (40%). CONCLUSION: In this series of 390 carotid operations, the procedure-related stroke/death rate was 0.8%. There were no differences between the stroke-death rates after primary carotid endarterectomy and operation for recurrent carotid stenosis. Operation for recurrent carotid stenosis is as safe and effective as primary carotid endarterectomy and should continue to be standard treatment.     

Carotid artery stenting: analysis of data for 105 patients at high risk

OBJECTIVES: Carotid artery stenting (CAS) has been recommended as an alternative to carotid endarterectomy (CEA) by some clinicians. However, recently published clinical trials have reported 30-day stroke and death rates of 10% to 12%. This prompted review of our experience with CAS in patients at high risk, to document our results and guide further use of CAS. METHODS: From September 1996 to the present, we performed 114 consecutive CAS procedures in 105 patients. Sixty-three patients were men (60%) and 42 patients were women (40%), with mean age of 70 years (range, 45-93 years). Indications for CAS included recurrent stenosis after previous CEA in 74 patients (65%), primary lesions in 32 patients at high risk (28%), and carotid stenosis with previous ipsilateral radiation therapy in 8 patients (7%). Asymptomatic stenosis (>80%) was managed in 70 patients (61%), and symptomatic lesions (>50%) were treated in 44 patients (39%). RESULTS: CAS was technically successful in all patients. Mean severity of stenosis before CAS was 87% +/- 6%, compared with 9% +/- 4% after CAS. Two patients (1.9%) died, 1 of reperfusion-intracerebral hemorrhage and 1 of myocardial infarction 10 days after discharge; and 1 patient (0.95%) had a stroke (retinal infarction), for a 30-day stroke and death rate of 2.85%. Two patients (1.9%) had transient neurologic events. No cranial nerve deficits were noted. No neurologic complications have been noted in the last 27 patients (26%). CONCLUSIONS: A 30-day stroke and death rate of 2.85% in our experience demonstrates acceptability of CAS as an alternative to repeat operation or primary CEA in patients at high risk or in patients with radiation-induced stenosis. We recommend further clinical investigation of CAS and participation in clinical trials by vascular surgeons.     

Carotid artery revascularization through a radiated field

OBJECTIVE: Extracranial carotid stenosis is a complication of external head and neck irradiation. The safety and durability of carotid artery revascularization through a radiated field has been debated. We describe the immediate and long-term results in a series of 27 consecutive patients who received treatment over 12 years. METHODS: From May 1990 to May 2002, 27 consecutive patients underwent 30 primary carotid artery revascularization procedures. All patients had received previous radiation therapy within a mean interval of 10 years (range, 1-26 years), with average radiation dose of 62 Gy (range, 50-70 Gy). Moderate to severe scarring of the skin or radiation fibrosis was present in three fourths of patients. Thirteen patients (48%) had undergone radical neck dissection, and 2 patients had a permanent tracheotomy. The indications for carotid surgery included high-grade (>70%) symptomatic stenosis in 18 patients (60%) and high-grade asymptomatic stenosis in 12 patients (40%). General anesthesia with systematic shunting was used in 18 patients (60%), and regional anesthesia with selective shunting was used in 12 patients (40%). Operations included standard carotid endarterectomy (n = 20), with patch angioplasty (n = 12) or direct closure (n = 8); carotid interposition bypass grafting (n = 7); and subclavian to carotid bypass grafting (n = 3). Primary closure of the surgical wound was performed in all procedures without any special muscular or skin flaps. All patients were followed up for a mean of 40 months (range, 3-99 months). RESULTS: There was one (3.3%) perioperative death, from massive intracerebral hemorrhage; and 1 patient had a transient ischemic attack. In-hospital complications included neck hematoma in 2 patients, which required surgical drainage in 1 patient. There was neither delayed wound healing nor infection. Twelve patients died during follow-up, of causes not related to treatment. None of the surviving patients had further stroke, and all remained asymptomatic. Follow-up duplex scans showed asymptomatic recurrent stenosis greater than 60% in 3 patients, 2 of whom with stenosis greater than 80% underwent repeat operation. Risk for recurrent stenosis greater than 60% at 18 months was 16.6%. Recurrent stenosis occurred in 2 of these patients after saphenous vein bypass, and in 1 patient after endarterectomy with vein patch angioplasty. CONCLUSION: The clinical results and sustained freedom from symptoms and stroke over 40-month follow-up suggests that carotid revascularization through a radiated field is a safe and durable procedure in patients at high surgical risk, despite a marked incidence of recurrent stenosis.     

Reoperations for carotid artery stenosis: role of primary and secondary reconstructions

PURPOSE: This is an analysis of the role of primary and secondary carotid artery reconstructions and systemic risk factors on the incidence and timing of reoperations and their perioperative and late outcomes. METHODS: This is a retrospective analysis of prospectively stored data. Between 1981 and 1999, 69 secondary carotid artery procedures were performed on 66 patients (3 were bilateral). Of these, 29 operations and patients came from my series of 1514 primary carotid endarterectomies (CEAs). Overall, secondary operations were performed on 37 women (1 bilateral) and 29 men (2 bilateral) with a mean age of 68 years. Indications for reoperation were transient ischemic attack in 27%, stroke in 12%, global ischemia in 9%, and asymptomatic > or = 70% recurrent stenosis in 52%. Secondary reconstruction was by saphenous vein patching in 57% (n = 39), Dacron patching in 29% (n = 20), polytetrafluoroethylene patch in 1% (n = 1), and interposition bypass graft in 13% (n = 9). The main outcome measures included restenosis, re-restenosis, and perioperative and late stroke and death. RESULTS: Reoperations were more frequent after originally primarily closed CEA (6.2%) than after patched CEA (1.6%, P =.01). Reoperations after Dacron-patched CEA occurred at a mean of 16 months compared with a mean of 84 months for vein-patched CEA (P <.001). Male sex and history of smoking have a slightly adverse but not statistically significant effect on the incidence and time of reoperation. Restenosis in the distal common carotid artery requiring reoperation had a near-linear rate of occurrence, whereas that in the internal carotid artery segment was bimodal with a higher incidence in the first 3 years and after 7 years. There were no (0%) 30-day perioperative deaths. There were two (2.9%) 30-day strokes (1 major, 1 minor). Over a mean follow-up of 50 months (range, 1-180), the Kaplan-Meier cumulative survival was 74% at 5 years and 54% at 10 years. This is significantly higher than late death after primary CEA independent of age. The cumulative freedom from stroke rate was 90% at 5 years and 86% at 10 years. After secondary procedures re-recurrent stenosis > or = 25% occurred in 25% (n = 17), > or = 50% in 13% (n = 9), and > or = 70% in 4% (n = 3). There was no statistically significant difference in stroke or re-restenosis rates between vein-patched, Dacron-patched, and bypassed reoperations, although re-recurrence tended to occur earlier after Dacron-patched than vein-patched procedures. Analysis of pooled literature data and the results of this study for stroke and re-restenosis outcomes by type secondary reconstruction (patch versus bypass graft) and by material (vein versus synthetic) give a balanced picture of near equality for each. Vein- and Dacron-patched arteries have similar outcomes, whereas polytetrafluoroethylene appears to be superior to vein and Dacron for interposition bypass graft. CONCLUSIONS: Secondary carotid artery operations are more frequent after primarily closed CEA than patched CEA. Perioperative mortality and stroke rates for reoperations are within the acceptable window of primary CEA. The incidence of late death after reoperations is higher than after primary CEA. The perioperative stroke, late stroke, and re-restenosis outcomes of vein- and Dacron-patched secondary operations are similar, as are those for patched and bypassed carotid arteries.     

A comparison of carotid angioplasty with stenting versus endarterectomy with regional anesthesia

Introduction: Percutaneous transluminal angioplasty with stenting (PTAS) has been considered a potential alternative to carotid endarterectomy (CEA) for stroke prevention. Interventionalists have suggested that PTAS carries less anesthetic risk than CEA. The treatment of carotid stenosis with local or regional anesthesia (LRA) allows direct intraprocedural neurologic evaluation and avoids the potential risks of general anesthesia. Methods: We retrospectively analyzed the clinical charts of 377 patients who underwent 414 procedures for the elective treatment of carotid stenosis in 433 cerebral hemispheres with LRA between August 1994 and May 1997. Group I (312 hemispheres) underwent PTAS, and group II (121 hemispheres) underwent CEA. Results: The indications for treatment included the following: asymptomatic severe stenosis (n = 272; 62.8%), transient ischemic attack (TIA; n = 100; 23.1%), and prior stroke (n = 61; 14.1%). The early neurologic results for the patients in group I (n = 268) included 11 TIAs (4.1%), 23 strokes (8.6%), and 3 deaths (1.1%). The early neurologic results for the patients in group II (n = 109) included 2 TIAs (1.8%), one stroke (0.9%), and no deaths. The total stroke and death rates were 9.7% for the patients in group I and 0.9% for the patients in group II (P = .0015). The cardiopulmonary events that led to additional monitoring were evident after 96 procedures in group I (32.8%) and 21 procedures in group II (17.4%; P = .002). Conclusion: PTAS carries a higher neurologic risk and requires more monitoring than CEA in the treatment of patients with carotid artery stenosis with LRA. The proposed benefit for the use of PTAS to avoid general anesthesia cannot be justified when compared with CEA performed with LRA. (J Vasc Surg 1998;28:397-403.)     

Safety and efficacy of reoperative carotid endarterectomy: a 14-year experience

BACKGROUND: Reoperative carotid endarterectomy (CEA) is an accepted treatment for recurrent carotid stenosis. With reports of a higher operative morbidity than primary CEA and the advent of carotid stenting, catheter-based therapy has been advocated as the primary treatment for this reportedly "high-risk" subgroup. This study reviews a contemporary experience with reoperative CEA to validate the high-risk categorization of these patients. METHODS: From 1989 to 2002, 153 consecutive, isolated (excluding CEA/coronary artery bypass graft and carotid bypass operations) reoperative CEA procedures were reviewed. Clinical and demographic variables potentially associated with the end points of perioperative morbidity, long-term durability, and late survival were assessed with multivariate analysis. RESULTS: There were 153 reoperative CEA procedures in 145 patients (56% men, 36% symptomatic) with an average age of 69 +/- 1.3 years. The average time from primary CEA (68% primary closure, 23% prosthetic, 9% vein patch) to reoperative CEA was 6.1 +/- 0.4 years (range, 0.3 to 20.4 years). At reoperation, patch reconstruction was undertaken in 93% of cases. The perioperative stroke rate was 1.9%, with no deaths or cardiac complications. Other complications included cranial nerve injury (1.3%) and hematoma (3.2%). Average follow-up after reoperative CEA was 4.4 +/- 0.3 years (range, 0.1 to 12.7 years), with an overall total stroke-free rate of 96% and a restenosis rate (>50%) by carotid duplex of 9.2%. Among variables assessed for association with restenosis after reoperative CEA, only younger age was found to be significant (66 +/- 2.5 years vs 70 +/- 0.7 years, P < .05). The all-cause long-term mortality rate was 29%. Multivariate analysis of long-term survival identified diabetes mellitus as having a negative impact (hazard ratio, 3.4 +/- 0.3, P < .05) and lipid-lowering agents as having a protective effect (hazard ratio, 0.42 +/- 0.4, P < .05) on survival. CONCLUSION: Reoperative CEA is a safe and durable procedure, comparable to reported standards for primary CEA, for long-term protection from stroke. These data do not support the contention that patients who require reoperative CEA constitute a "high-risk" subgroup in whom reoperative therapy should be avoided.     

Selective shunting with eversion carotid endarterectomy

PURPOSE: The consensus is that eversion carotid endarterectomy (CEA) is a safe, effective, and durable surgical technique. Concern remains, however, regarding insertion of a shunt during the procedure. We studied the advisability of shunting with eversion CEA by comparing patients who underwent eversion CEA with and without shunting. METHODS: Over 9 years, 624 primary eversion CEAs were performed in 580 selected patients to treat symptomatic (n = 398, 63.8%) and asymptomatic (n = 226, 36.2%) carotid lesions. All eversion CEAs were performed by the same surgeon (E.B.), with the patient under deep general anesthesia, with continuous electroencephalographic (EEG) monitoring for selective shunting, based exclusively on EEG changes consistent with cerebral ischemia. A Pruitt-Inahara shunt was used in 43 eversion CEAs (6.9%). All patients underwent postoperative duplex ultrasound scanning and clinical follow-up at 1, 6, and 12 months and once a year thereafter. Mean follow-up was 52 months (range, 3-91 months). The main end points were perioperative (30-day) stroke and death, and recurrent stenosis. RESULTS: No perioperative death occurred in this series. Overall, ischemic perioperative stroke occurred in 4 of 624 patients (0.6%). Two strokes were minor and two were major. Only one (major) stroke occurred in the group with shunt insertion (1 of 43, 2.3%; P = not significant); the everted internal carotid artery was patent. Long-term follow-up was performed in all living patients. There was no late recurrent stenosis (>50%), and one late asymptomatic occlusive event occurred in the group without shunt insertion. CONCLUSIONS: Shunt insertion can be safely performed during eversion CEA. Perioperative mortality and morbidity after eversion CEA are not statistically modified with shunting.     

Restenosis after eversion vs patch closure carotid endarterectomy

OBJECTIVES: Recurrent stenosis after carotid endarterectomy (CEA), previously reported to occur in 1%/year after operation, is the finite limitation of CEA. Eversion endarterectomy has a perceived lower incidence of recurrent stenosis, although data to support this contention are conflicting. The goal of the present study was to compare the late anatomic results of patch closure (PC) vs eversion CEA. METHODS: Between January 1, 1995 and June 30, 2005, 950 CEA were performed by the senior author with adoption of eversion (EV) as the primary technique as of January 1, 2001. With minimum of 1-year follow-up by study inclusion criteria, complete follow-up data (including a duplex scan) was available for 155 PC and 135 EV patients. Incidence of moderate (50% to 70%) and severe (>70%) restenosis was examined at < or =2 months and >1 year after operation. Study end-points included late stroke, survival, and freedom from restenosis (moderate and severe) and were assessed by actuarial methods. RESULTS: There were no differences in relevant demographic/clinical parameters, indication for surgery (69% overall asymptomatic) or early perioperative stroke/death (1.1% overall; P = .25) between PC and EV. After correction for different mean follow-up intervals (PC = 5.5 years vs EV = 3.5 years) by actuarial methods, there was no significant difference in late moderate (P = .91) or severe (P = .54) recurrent stenosis between PC and EV. In the group of patients with at least 1-year follow-up, 11/290 (3.8%) patients (4/135 EV, 7/155 PC; P = .39) required reintervention on their operated carotid artery at a cumulative follow-up interval of 4.5 years. Three strokes (3/290; 1.1%) occurred during late follow-up, all in the PC group, with only one related to the operated carotid artery. Late survival was similar between EV and PC, (P = .86). Female gender (odds ratio [OR] 3.72[1.02-13.5], P = .046) was associated with severe restenosis irrespective of surgical technique. Univariate analysis also showed that female gender (OR 7.6[CI: 0.88-66.7], P = .042) was associated with late stroke. CONCLUSION: These findings indicate that restenosis rates are similar between eversion and patch CEA and likely represent biological remodeling phenomenon rather than technical variations of operations. While EV offers distinct advantages in certain anatomic circumstances, adoption of EV with the hope of decreasing restenosis is not warranted.     

Durability of carotid endarterectomy for treatment of symptomatic and asymptomatic stenoses

PURPOSE: Although many studies have well established that carotid endarterectomy (CEA) is beneficial in selected patients with severe carotid disease, only a few large studies have focused on the durability of the surgical procedure. Carotid artery angioplasty and stenting (CAS) has recently been proposed as a potential alternative to CEA. We analyzed the incidence of late occlusion and recurrent stenosis after CEA. METHODS: Over 13 years 1000 patients underwent 1150 CEA procedures to treat symptomatic and asymptomatic high-grade carotid stenosis. CEA procedures involving either traditional CEA with patching (n = 302) or eversion CEA (n = 848) were all performed by the same surgeon, with patients under deep general anesthesia and cerebral protection involving continuous electroencephalographic monitoring for selective shunting. All patients underwent postoperative duplex ultrasound scanning and clinical follow-up at 1, 6, and 12 months, and yearly thereafter. New neurologic events, late occlusions, and recurrent stenoses 50% or greater were recorded. Complete follow-up (mean, 6.2 years; range, 6-156 months) was obtained in 95% of patients (949 of 1000), for an overall average of 95% of procedures (1092 of 1150). Survival analysis was performed with the Kaplan-Meier life table method. RESULTS: Perioperative (30-day) mortality rate was 0.3% (3 of 1000), and stroke rate was 0.9% (11 of 1150), with a combined mortality and stroke rate of 1.2%. The incidence of late occlusion and recurrent stenosis 70% or greater was 0.6% and 0.5%, respectively, with a combined occlusion and restenosis rate of 1.1%. Kaplan-Meier analysis showed that the rate of freedom from occlusion, restenosis 70% or greater, and combined occlusion and restenosis 70% or greater at 12 years was 99,4%, 99.5%, and 98.8%, respectively. Occlusion and restenosis developed asymptomatically. CONCLUSIONS: CEA is a low-risk procedure for treating severe symptomatic and asymptomatic carotid disease, with excellent long-term durability. Proponents of CAS should bear this in mind before considering CAS as a routine alternative to CEA.     

Duplex scan surveillance after carotid angioplasty and stenting: a rational definition of stent stenosis

OBJECTIVE: A duplex ultrasound (DUS) surveillance algorithm used after carotid endarterectomy (CEA) was applied to patients after carotid stenting and angioplasty (CAS) to determine the incidence of high-grade stent stenosis, its relationship to clinical symptoms, and the outcome of reintervention. METHODS: In 111 patients who underwent 114 CAS procedures for symptomatic (n = 62) or asymptomatic (n = 52) atherosclerotic or recurrent stenosis after CEA involving the internal carotid artery (ICA), DUS surveillance was performed 300 cm/s, diastolic velocity >125 cm/s, internal carotid artery stent/proximal common carotid artery ratio >4) involving the stented arterial segment prompted diagnostic angiography and repair when >75% diameter-reduction stenosis was confirmed. Criteria for >50% CAS stenosis was a PSV >150 cm/s with a PSV stent ratio >2. RESULTS: All 114 carotid stents were patent on initial DUS imaging, including 90 (79%) with PSV <150 cm/s (94 +/- 24 cm/s), 23 (20%) with PSV >150 cm/s (183 +/- 34 cm/s), and one with high-grade, residual stenosis (PSV = 355). During subsequent surveillance, 81 CAS sites (71%) exhibited no change in stenosis severity, nine sites demonstrated stenosis regression to <50% diameter reduction, and five sites developed velocity spectra of a high-grade stenosis. Angiography confirmed >75% diameter reduction in all six CASs with DUS-detected high-grade stenosis, all patients were asymptomatic, and treatment consisted of endovascular (n = 5) or surgical (n = 1) repair. During the mean 33-month follow-up period, three patients experienced ipsilateral, reversible neurologic events at 30, 45, and 120 days after CAS; none was associated with severe stent stenosis. No stent occlusions occurred, and no patient with >50% CAS stenosis on initial or subsequent testing developed a permanent ipsilateral permanent neurologic deficit or stroke-related death. CONCLUSION: DUS surveillance after CAS identified a 5% procedural failure rate due to the development of high-grade in-stent stenosis. Both progression and regression of stent stenosis severity was observed on serial testing, but 70% of CAS sites demonstrated velocity spectra consistent with <50% diameter reduction. The surveillance algorithm used, including reintervention for asymptomatic high-grade CAS stenosis, was associated with stent patency and the absence of disabling stroke.     

Cerebral tomographic findings in patients undergoing carotid endarterectomy for asymptomatic carotid stenosis: short-term and long-term implications

Purpose: Preoperative cerebral imaging has been considered not to be cost-effective in carotid endarterectomy (CEA) for asymptomatic carotid stenosis. Yet, silent brain infarction (SBI) has been associated with the embolization potential of a severe carotid stenosis. Thus the presence of SBI may represent an additional indication for CEA in asymptomatic patients. We examined the predictive value of preoperatively detected silent cerebral lesions on early and late outcomes in patients undergoing CEA for asymptomatic carotid stenosis. Methods: Preoperative cerebral tomographic (CT) scans performed on 301 asymptomatic patients undergoing 346 CEAs from 1986 to 1995 were reviewed by a single neuroradiologist blinded to patients' records. Mean follow-up was 67.3 months (range, 24-130 months). The degree of internal carotid lumen reduction was measured bilaterally in all patients (602 carotid arteries); carotid stenosis of 60% or more was found in 399 carotid arteries. Results: Of the 103 (34%) CT scans positive for cerebral lesions, 58% were lacunar. No significant association was observed between the side of the cerebral lesion on CT scan and the severity of the corresponding carotid stenosis; 38 silent lesions were detected in the 203 hemispheres ipsilateral to carotid stenoses that were less than 60% versus 95 SBIs in the 399 hemispheres ipsilateral to carotid stenoses that were 60% or more (19% vs 24%; P = .2). There were no significant differences in the perioperative stroke/death rate in patients with or without cerebral CT lesions (2% vs 1%; odds ratio, 1.94; P = .6). Mortality rate during follow-up was 22% in patients with preoperative SBI and 15% in patients without SBI (P = .1). However, actuarial survival at 10 years was shorter (P = .02) in patients with SBI. Late stroke occurred in 11% of patients with preoperative SBI and in 3% of patients without preoperative SBI (P = .006). Cox regression analysis showed that both preoperative lacunar and nonlacunar infarctions were independent predictors of late stroke (hazard ratio, 3.6; P = .04; and hazard ratio, 7.1; P = .001; respectively). Conclusion: In our experience, preoperative SBI did not occur more frequently in the hemisphere ipsilateral to asymptomatic severe carotid stenosis. Although our study lacks a medically treated control group, our data show that SBI is predictive of poor neurologic outcome in asymptomatic patients undergoing CEA. We conclude that CT before CEA, selectively applied, provides information on long-term neurologic prognosis and that a less aggressive attitude towards CEA in asymptomatic patients with SBI may be justified. (J Vasc Surg 1999;29:995-1005.)     

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).     

In-stent recurrent stenosis after carotid artery stenting: life table analysis and clinical relevance

OBJECTIVES: Carotid artery stenting has been proposed as an alternative to carotid endarterectomy in cerebral revascularization. Although early results from several centers have been encouraging, concerns remain regarding long-term durability of carotid artery stenting. We report the incidence, characteristics, and management of in-stent recurrent stenosis after long-term follow-up of carotid artery stenting. METHODS: Carotid artery stenting (n = 122) was performed in 118 patients between September 1996 and March 2003. Indications included recurrent stenosis after previous carotid endarterectomy (66%), primary lesions in patients at high-risk (29%), and previous ipsilateral cervical radiation therapy (5%). Fifty-five percent of patients had asymptomatic stenosis; 45% had symptomatic lesions. Each patient was followed up with serial duplex ultrasound scanning. Selective angiography and repeat intervention were performed when duplex ultrasound scans demonstrated 80% or greater in-stent recurrent stenosis. Data were prospectively recorded, and were statistically analyzed with the Kaplan-Meier method and log-rank test. RESULTS: Carotid artery stenting was performed successfully in all cases, with the WallStent or Acculink carotid stent. Thirty-day stroke and death rate was 3.3%, attributable to retinal infarction (n = 1), hemispheric stroke (n = 1), and death (n = 2). Over follow-up of 1 to 74 months (mean, 18.8 months), 22 patients had in-stent recurrent stenosis (40%-59%, n = 11; 60%-79%, n = 6; > or =80%, n = 5), which occurred within 18 months of carotid artery stenting in 13 patients (60%). None of the patients with in-stent recurrent stenosis exhibited neurologic symptoms. Life table analysis and Kaplan-Meier curves predicted cumulative in-stent recurrent stenosis 80% or greater in 6.4% of patients at 60 months. Three of five in-stent recurrent stenoses occurred within 15 months of carotid artery stenting, and one each occurred at 20 and 47 months, respectively. Repeat angioplasty was performed once in 3 patients and three times in 1 patient, and repeat stenting in 1 patient, without complications. One of these patients demonstrated asymptomatic internal carotid artery occlusion 1 year after repeat intervention. CONCLUSIONS: Carotid artery stenting can be performed with a low incidence of periprocedural complications. The cumulative incidence of clinically significant in-stent recurrent stenosis (> or =80%) over 5 years is low (6.4%). In-stent restenosis was not associated with neurologic symptoms in the 5 patients noted in this cohort. Most instances of in-stent recurrent stenosis occur early after carotid artery stenting, and can be managed successfully with endovascular techniques.