A prospective, randomized study of saphenous vein patching versus synthetic patching during carotid endarterectomy

Patch Infection Following Carotid Endarterectomy: A Single-Center Audit and Literature Review

INTRODUCTION

Carotid endarterectomy (CEA) is a surgical procedure that carries a rare but serious risk of patch infection. This study examines the management and outcomes of patch infections in CEA patients treated in our department over 23 years. A literature review of studies on prosthetic patch infection following CEA published from January 1992 up to December 31, 2022 was also carried out.

METHODS

We conducted a retrospective audit of patients who underwent CEA in a hospital in Athens, Greece, between January 1, 1999, and December 31, 2022.

RESULTS

Between January 1999 and December 2022, we treated seven patients with carotid patch infections who had their original CEA at our department. Staphylococcus epidermidis and Staphylococcus aureus were the most common infecting organisms. One patient (14%) died from hemorrhagic shock before surgery, while the remaining six (86%) underwent debridement, patch excision, and great saphenous vein patching. No peri-operative deaths or strokes occurred, and there were no re-infections during a median follow-up of 159 months.

CONCLUSIONS

Excision of infected material followed by revascularization using a vein graft remains the prevailing treatment.

An international, multispecialty, expert-based Delphi Consensus document on controversial issues in the management of patients with asymptomatic and symptomatic carotid stenosis

OBJECTIVE

Despite the publication of various national/international guidelines, several questions concerning the management of patients with asymptomatic (AsxCS) and symptomatic (SxCS) carotid stenosis remain unanswered. The aim of this international, multi-specialty, expert-based Delphi Consensus document was to address these issues to help clinicians make decisions when guidelines are unclear.

METHODS

Fourteen controversial topics were identified. A three-round Delphi Consensus process was performed including 61 experts. The aim of Round 1 was to investigate the differing views and opinions regarding these unresolved topics. In Round 2, clarifications were asked from each participant. In Round 3, the questionnaire was resent to all participants for their final vote. Consensus was reached when ≥75% of experts agreed on a specific response.

RESULTS

Most experts agreed that: (1) the current periprocedural/in-hospital stroke/death thresholds for performing a carotid intervention should be lowered from 6% to 4% in patients with SxCS and from 3% to 2% in patients with AsxCS; (2) the time threshold for a patient being considered "recently symptomatic" should be reduced from the current definition of "6 months" to 3 months or less; (3) 80% to 99% AsxCS carries a higher risk of stroke compared with 60% to 79% AsxCS; (4) factors beyond the grade of stenosis and symptoms should be added to the indications for revascularization in AsxCS patients (eg, plaque features of vulnerability and silent infarctions on brain computed tomography scans); and (5) shunting should be used selectively, rather than always or never. Consensus could not be reached on the remaining topics due to conflicting, inadequate, or controversial evidence.

CONCLUSIONS

The present international, multi-specialty expert-based Delphi Consensus document attempted to provide responses to several unanswered/unresolved issues. However, consensus could not be achieved on some topics, highlighting areas requiring future research.

Literature review of primary versus patching versus eversion as carotid endarterectomy closure

BACKGROUND

Which type of closure after carotid endarterectomy (CEA), whether primary, patching, or eversion, will provide the optimal results has remained controversial. In the present study, we compared the results of randomized controlled trials (RCTs) and systematic meta-analyses of the various types of closure.

METHODS

We conducted a PubMed literature review search to find studies that had compared CEA with primary closure, CEA with patching, and/or eversion CEA (ECEA) during the previous three decades with an emphasis on RCTs, previously reported systematic meta-analyses, large multicenter observational studies (Vascular Quality Initiative data), and recent single-center large studies.

RESULTS

The results from RCTs comparing primary patching vs primary closure were as follows. Most of the randomized trials showed CEA with patching was superior to CEA with primary closure in lowering the perioperative stroke rates, stroke and death rates, carotid thrombosis rates, and late restenosis rates. These studies also showed no significant differences between the preferential use of several patch materials, including synthetic patches (polyethylene terephthalate [Dacron; DuPont, Wilmington, Del], Acuseal [Gore Medical, Flagstaff, Ariz], polytetrafluoroethylene, or pericardial patches) and vein patches (saphenous or jugular). The results from observational studies comparing patching vs primary closure were as follows. The Vascular Study Group of New England data showed that the use of patching increased from 71% to 91% (P < .001). Also, the 1-year restenosis and occlusion (P < .01) and 1-year stroke and transient ischemic attack (P < .03) rates were significantly lower statistically with patch closure. The results from the RCTs comparing ECEA vs conventional CEA (CCEA) were as follows. Several RCTs that had compared ECEA with CCEA showed equivalency of CCEA vs ECEA (level 1 evidence) with patching in the perioperative carotid thrombosis and stroke rates. At 4 years after treatment, the incidence of carotid stenosis was lower for ECEA than for primary closure (3.6% vs 9.2%; P = .01) but was comparable between patching and eversion (1.5% for patching vs 2.8% for eversion).

CONCLUSIONS

Routine carotid patching or ECEA was superior to primary closure (level 1 evidence). We found no significant differences between the preferential use of several patch materials. The rates of significant post-CEA stenosis for CEA with patching was similar to that with ECEA, and both were superior to primary closure.

Patches of different types for carotid patch angioplasty

BACKGROUND

Extracranial carotid artery stenosis is the major cause of stroke, which can lead to disability and mortality. Carotid endarterectomy (CEA) with carotid patch angioplasty is the most popular technique for reducing the risk of stroke. Patch material may be made from an autologous vein, bovine pericardium, or synthetic material including polytetrafluoroethylene (PTFE), Dacron, polyurethane, and polyester. This is an update of a review that was first published in 1996 and was last updated in 2010.

OBJECTIVES

To assess the safety and efficacy of different types of patch materials used in carotid patch angioplasty. The primary hypothesis was that a synthetic material was associated with lower risk of patch rupture versus venous patches, but that venous patches were associated with lower risk of perioperative stroke and early or late infection, or both.

SEARCH METHODS

We searched the Cochrane Stroke Group trials register (last searched 25 May 2020); the Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 4), in the Cochrane Library; MEDLINE (1966 to 25 May 2020); Embase (1980 to 25 May 2020); the Index to Scientific and Technical Proceedings (1980 to 2019); the Web of Science Core Collection; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) portal. We handsearched relevant journals and conference proceedings, checked reference lists, and contacted experts in the field.

SELECTION CRITERIA

Randomised and quasi-randomised trials (RCTs) comparing one type of carotid patch with another for CEA.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility, risk of bias, and trial quality; extracted data; and determined the quality of evidence using the GRADE approach. Outcomes, for example, perioperative ipsilateral stroke and long-term ipsilateral stroke (at least one year), were collected and analysed.

MAIN RESULTS

We included 14 trials involving a total of 2278 CEAs with patch closure operations: seven trials compared vein closure with PTFE closure, five compared Dacron grafts with other synthetic materials, and two compared bovine pericardium with other synthetic materials. In most trials, a patient could be randomised twice and could have each carotid artery randomised to different treatment groups. Synthetic patch compared with vein patch angioplasty Vein patch may have little to no difference in effect on perioperative ipsilateral stroke between synthetic versus vein materials, but the evidence is very uncertain (odds ratio (OR) 2.05, 95% confidence interval (CI) 0.66 to 6.38; 5 studies, 797 participants; very low-quality evidence). Vein patch may have little to no difference in effect on long-term ipsilateral stroke between synthetic versus vein materials, but the evidence is very uncertain (OR 1.45, 95% CI 0.69 to 3.07; P = 0.33; 4 studies, 776 participants; very low-quality evidence). Vein patch may increase pseudoaneurysm formation when compared with synthetic patch, but the evidence is very uncertain (OR 0.09, 95% CI 0.02 to 0.49; 4 studies, 776 participants; very low-quality evidence). However, the numbers involved were small. Dacron patch compared with other synthetic patch angioplasty Dacron versus PTFE patch materials  PTFE patch may reduce the risk of perioperative ipsilateral stroke (OR 3.35, 95% CI 0.19 to 59.06; 2 studies, 400 participants; very low-quality evidence). PTFE patch may reduce the risk of long-term ipsilateral stroke (OR 1.52, 95% CI 0.25 to 9.27; 1 study, 200 participants; very low-quality evidence). Dacron may result in an increase in perioperative combined stroke and transient ischaemic attack (TIA) (OR 4.41 95% CI 1.20 to 16.14; 1 study, 200 participants; low-quality evidence) when compared with PTFE. Early arterial re-stenosis or occlusion (within 30 days) was also higher for Dacron patches. During follow-up for longer than one year, more 'any strokes' (OR 10.58, 95% CI 1.34 to 83.43; 2 studies, 304 participants; low-quality evidence) and stroke/death (OR 6.06, 95% CI 1.31 to 28.07; 1 study, 200 participants; low-quality evidence) were reported with Dacron patch closure, although numbers of outcome events were small. Dacron patch may increase the risk of re-stenosis when compared with other synthetic materials (especially with PTFE), but the evidence is very uncertain (OR 3.73, 95% CI 0.71 to 19.65; 3 studies, 490 participants; low-quality evidence). Bovine pericardium patch compared with other synthetic patch angioplasty Bovine pericardium versus PTFE patch materials  Evidence suggests that bovine pericardium patch results in a reduction in long-term ipsilateral stroke (OR 4.17, 95% CI 0.46 to 38.02; 1 study, 195 participants; low-quality evidence). Bovine pericardial patch may reduce the risk of perioperative fatal stroke, death, and infection compared to synthetic material (OR 5.16, 95% CI 0.24 to 108.83; 2 studies, 290 participants; low-quality evidence for PTFE, and low-quality evidence for Dacron; OR 4.39, 95% CI 0.48 to 39.95; 2 studies, 290 participants; low-quality evidence for PTFE, and low-quality evidence for Dacron; OR 7.30, 95% CI 0.37 to 143.16; 1 study, 195 participants; low-quality evidence, respectively), but the numbers of outcomes were small. The evidence is very uncertain about effects of the patch on infection outcomes.

AUTHORS' CONCLUSIONS

The number of outcome events is too small to allow conclusions, and more trial data are required to establish whether any differences do exist. Nevertheless, there is little to no difference in effect on perioperative and long-term ipsilateral stroke between vein and any synthetic patch material. Some evidence indicates that other synthetic patches (e.g. PTFE) may be superior to Dacron grafts in terms of perioperative stroke and TIA rates, and both early and late arterial re-stenosis and occlusion. Pseudoaneurysm formation may be more common after use of a vein patch than after use of a synthetic patch. Bovine pericardial patch, which is an acellular xenograft material, may reduce the risk of perioperative fatal stroke, death, and infection compared to other synthetic patches. Further large RCTs are required before definitive conclusions can be reached.

A meta-analysis of randomized trials comparing bovine pericardium and other patch materials for carotid endarterectomy

OBJECTIVE

Patch angioplasty during carotid endarterectomy is commonly used to treat symptomatic and asymptomatic carotid artery stenosis. The objective of the present study was to compare the different patch materials that are currently available (synthetic vs venous vs bovine pericardium) in terms of short- and long-term outcomes.

METHODS

This study was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and eligible randomized control trials were identified through a comprehensive search of PubMed, Scopus, and Cochrane Central published until September 2017. A meta-analysis was conducted with the use of a random effects model. The I² statistic was used to assess for heterogeneity. The primary study end point was the incidence of long-term restenosis. Secondary study end points were 30-day stroke, transient ischemic attack (TIA), myocardial infarction, neck wound infection, local hematoma, carotid artery thrombosis, cranial nerve injury, long-term stroke incidence, and death.

RESULTS

Eighteen studies and 3234 patients were included. The risk of 30-day stroke (relative risk [RR], 1.00; 95% confidence interval [CI], 0.45-2.19; I² = 0%), TIA (RR, 1.14; 95% CI, 0.41-3.19; I² = 0%), myocardial infarction (odds ratio, 0.75; 95% CI, 0.14-3.97; I² = 0%), death (RR, 0.53; 95% CI, 0.21-1.34; I² = 0%), wound infection (RR, 1.84; 95% CI, 0.43-7.81; I² = 0%), carotid artery thrombosis (RR, 1.47; 95% CI, 0.44-4.97; I² = 0%), cranial nerve palsy (RR, 1.21; 95% CI, 0.53-2.77; I² = 0%), and long-term stroke (RR, 2.33; 95% CI, 0.76-7.10; I² = 0%), death (RR, 1.09; 95% CI, 0.65-1.83; I² = 0%) and restenosis of greater than 50% (RR, 0.48; 95% CI, 0.19-1.20; I² = 0%) were similar between the synthetic vs venous patch groups. Also, no differences in terms of 30-day stroke (RR, 0.31; 95% CI, 0.02-5.16; I² = 63.1%), TIA (RR, 0.49; 95% CI, 0.14-1.76; I² = 0%), death (RR, 0.74; 95% CI, 0.05-10.51; I² = 31.7%), carotid artery thrombosis (RR, 0.13; 95% CI, 0.02-1.07; I² = 0%), and long-term restenosis of greater than 70% (RR, 0.15; 95% CI, 0.01-2.29; I² = 70.9%) were detected between the synthetic polytetrafluoroethylene and Dacron patch groups. The comparison between the bovine pericardium vs synthetic patch did not yield any statistically significant results in terms of 30-day stroke (RR, 1.44; 95% CI, 0.19-10.79; I² = 12.7%), TIA (RR, 1.05; 95% CI, 0.11-10.27; I² = 0%), local neck hematoma (RR, 4.01; 95% CI, 0.46-34.85; I² = 0%), and death (RR, 4.01; 95% CI, 0.46-34.85; I² = 0%).

CONCLUSIONS

Closure of the carotid arteriotomy with any of the studied patch materials seems to be similar in terms of short- and long-term end points. However, additional randomized trials with adequate follow-up periods are needed to compare bovine pericardium patches with other patch materials.

Autologous tissue patches acquire vascular identity depending on the environment

Vascular identity is genetically determined, but can be altered during surgical procedures. We hypothesized that the environment of the procedure critically alters the identity of autologous tissue patches implanted into the arterial or venous environment. Autologous jugular vein or carotid artery was used as a patch to repair a rat aorta or inferior vena cava. In the aortic environment patches contained neointimal cells that were CD34/Ephrin-B2-dual positive but not CD34/Eph-B4-dual positive; patches expressed Ephrin-B2, notch-4 and dll-4 but not Eph-B4 and COUP-TFII. In the venous environment patches contained neointimal cells that were CD34/Eph-B4-dual positive but not CD34/Ephrin-B2-dual positive; patches expressed Eph-B4 and COUP-TFII but not Ephrin-B2, notch-4 and dll-4. These data show that autologous tissue patches heal by acquisition of the vascular identity determined by the environment into which they are implanted, suggesting some plasticity of adult vascular identity.

Late Dacron Patch Inflammatory Reaction after Carotid Endarterectomy

OBJECTIVE

The aim was to analyse the incidence and presentation of carotid patch inflammatory reactions following carotid endarterectomy (CEA).

METHODS

This was a cohort study using a prospectively maintained database. All patients who underwent elective CEA at a tertiary vascular centre between 2002 and 2016 were included. Computed tomography scan angiogram, duplex scan, and leucocyte scintigraphy were used to assess patients with suspected inflammatory patch complications. Re-intervention procedures and outcomes were noted. Histopathology and organisms cultured from the harvested material during re-intervention were assessed.

RESULTS

During the study period, 633 patients underwent elective CEA. Fifty-one underwent eversion endarterectomy: 111 did not require a patch, whereas 471 patients had a patch repair. Four hundred and twenty eight had a Dacron patch repair and 43 a biological patch. Eight patients returned with late Dacron patch inflammatory complications (1.3% of all CEA and 1.9% of Dacron patch closures) after a period ranging from 18 months to 7 years (mean 4.1 ± 2.1 years). Seven of the eight patients underwent surgical re-intervention, and the eighth patient was deemed high surgical risk. One patient underwent a vein bypass, three had vein patch repair, one required internal carotid artery (ICA) ligation after patch excision, and two were managed by debridement, with omohyoid and sternomastoid muscle covering of the patch. The patient who required ICA ligation suffered a fatal stroke. The remaining patients had a satisfactory outcome. All patients showed evidence of foreign body reaction in pathological examination with no pathological organism cultured from swabs or tissue harvested during surgery.

CONCLUSION

Late wound complications after CEA may be related to inflammatory reaction of the Dacron patch rather than infection. Infection should be excluded first. Reconstruction with vein is effective. However, debridement with sternomastoid and omohyoid muscle covering of the patch may be considered in high risk patients after exclusion of infection with regular follow-up.

The Influence of Collagen Impregnation of a Knitted Dacron Patch Used in Carotid Endarterectomy

BACKGROUND

In selected populations, carotid endarterectomy (CEA) reduces long-term stroke risk. Studies have shown increased risk of restenosis with use of a collagen-impregnated Dacron patch compared to a polytetrafluorethylene patch. There is concern that collagen impregnation may initiate thrombosis or promote restenosis due to platelet activation. We performed a retrospective analysis of our CEA experience with routine patching using knitted Dacron patches with (Hemashield) and without (Sauvage) collagen impregnation.

METHODS

Our database was queried for all CEAs between January 2006 and December 2010. Seven surgeons performed 655 CEAs. Patients were excluded if no patch was used (n = 1), a primary CEA was performed before study period or by other surgeons (n = 11), or the patch type was indeterminable (n = 38). Demographics, clinical data, and outcomes were compared between the collagen-impregnated (C, Hemashield) group and non-collagen-impregnated (NC, Sauvage) group.

RESULTS

A total of 605 CEAs were analyzed (395 C and 210 NC). Demographics were similar except for coronary artery disease (C 54.3% vs. NC 41.6%, P = 0.003). There was no statistically significant difference in 30-day (C 99.7% vs. NC 99.5%, P > 0.99) or 5-year survival (C 80.0% vs. NC 83.7%, P = 0.26) or 30-day stroke rate (C 0.3% vs. NC 1.0%, P = 0.28). No late ipsilateral strokes occurred during 5-year follow-up. The 5-year freedom from restenosis >30% (C 85.3% vs. NC 86.4%, P = 0.33), restenosis >50% (C 94.5% vs. NC 95.5%, P = 0.44), and restenosis >70% (C 98.6% vs. NC 98.9%, P = 0.73) were similar. Two patients underwent carotid stenting for restenosis >70%. Two patients (both in the C group) developed occlusion of the carotid artery.

CONCLUSIONS

The thrombosis and restenosis rates in the 2 groups were similar. This suggests that collagen-impregnated patches do not initiate thrombosis or increase restenosis rates after CEA.

Factors Affecting Recurrent Carotid Stenosis

Recurrent carotid stenosis is an ongoing process that may develop at or near the site of an operational or interventional procedure to treat an atheromatous stenosis. Although such a restenosis is most often initially without symptoms, as the disease progresses it may become symptomatic, and thus endanger the patient's life. Such patients are therefore candidates for revisional surgery. Extensive research investigation and numerous studies have incriminated several risk factors as predisposing conditions for recurrent carotid stenosis. The definite role of each predisposing factor, however, is still widely debated. Clarifying the extent of involvement of each factor in the pathogenesis of carotid restenosis is indeed demanding, as it would contribute enormously to the identification of the group of high-risk patients, and, therefore, determine the therapeutic approach in these patients.

Selective Patch Angioplasty and Intraoperative Shunting in Carotid Endarterectomy: A Single-Center Review of 141 Procedures

Objective: Open surgical treatment of carotid artery stenosis, namely, carotid endarterectomy (CEA), has evolved since its inception in 1953. Despite improvements in the treatment of carotid occlusive disease through technological and surgical innovations, the use of patch grafting in CEA’s remains controversial. We evaluate the durability of the primary closure and the safety of selective shunting during carotid endarterectomy (CEA) as determined by intraoperative EEG and postoperative outcomes.

Methods: A consecutive series of CEA’s performed by the senior author at a single academic medical center from 2001 to 2012 were reviewed. All cases were performed under continuous intraoperative electroencephalography (EEG). Patch angioplasty was used in cases where there was tortuosity of the vessel within the region of the endarterectomy and narrow vessel diameter at the distal end of the arteriotomy. Shunting was used when intraoperative EEG showed a > 50% reduction in a waveform in any lead. Patients were evaluated for restenosis via imaging or ultrasound at six months and subsequently annual follow-up.

Results: One hundred and forty-one CEA’s were performed on 132 (76 male, 56 female) patients with an average age of 71 years (range: 40–95 years). Four (3%) cases required patch angioplasty and three (2%) required intraoperative shunts. The cross-clamp time ranged from 22 to 74 minutes, and the duration increased with the use of shunts and patches. Complications were rare and included recurrent stenosis (n=2), postoperative transient ischemic attack (n=1), ischemic stroke in (n=1), temporary hypoglossal nerve weakness (n=2), temporary marginal mandibular nerve weakness (n=6), and neck hematoma (n=1).

Conclusion: Intraoperative EEG data suggests that primary closure and selective shunting in CEA can result in outcomes comparable with routine patch angioplasty and shunting.

Carotid Endarterectomy: A Review

Background:

Since the validation of carotid endarterectomy (CEA) as an effective means of stroke prevention, there has been renewed interest in its best indications and methods, as well as in how it compares to carotid angioplasty and stenting (CAS). This review examines these topics, as well as the investigation of carotid stenosis and the role of auditing and reporting CEAresults.

Investigation:

Brain imaging with CTor MRI should be obtained in patients considered for CEA, in order to document infarction and rule out mass lesions. Carotid investigation begins with ultrasound and, if results agree with subsequent, good-quality MRAor CTangiography, treatment can be planned and catheter angiography avoided. An equally acceptable approach is to proceed directly from ultrasound to catheter angiography, which is still the gold-standard in carotid artery assessment.

Indications:

Appropriate patients for CEA are those symptomatic with transient ischemic attacks or nondisabling stroke due to 70-99% carotid stenosis; the maximum allowable stroke and death rate being 6%. Uncertain candidates for CEA are those with 50 - 69% symptomatic stenosis, and those with asymptomatic stenosis ≥ 60% but, if selected carefully on the basis of additional risk factors (related to both the carotid plaque and certain patient characteristics), some will benefit from surgery. Asymptomatic patients will only benefit if surgery can be provided with exceptionally low major complication rates (3% or less). Inappropriate patients are those with less than 50% symptomatic or 60% asymptomatic stenosis, and those with unstable medical or neurological conditions.

Techniques:

Carotid endarterectomy can be performed with either regional or general anaesthesia and, for the latter, there are a number of monitoring techniques available to assess cerebral perfusion during carotid cross-clamping. While monitoring cannot be considered mandatory and no single monitoring technique has emerged as being clearly superior, EEG is most commonly used. “Eversion” endarterectomy is a variation in surgical technique, and there is some evidence that more widely practiced patch closure may reduce the acute risk of operative stroke and the longer-term risk of recurrent stenosis.

Carotid angioplasty and stenting:

Experience with this endovascular and less invasive procedure grows, and its technology continues to evolve. Some experienced therapists have reported excellent results in case series and a number of randomized trials are now underway comparing CAS to CEA. However, at this time it is premature to incorporate CAS into routine practice replacing CEA.

Auditing:

It has been shown that auditing of CEA indications and results with regular feed-back to the operating surgeons can significantly improve the performance of this operation. Carotid endarterectomy auditing is recommended on both local and regional levels.

Pretreatment of pericardial patches with antibiotics does not alter patch healing in vivo

BACKGROUND

Pretreatment with antibiotics is commonly performed before surgical implantation of prosthetic materials. We previously showed that pericardial patches are infiltrated by macrophages and arterial stem cells after implantation into an artery. We hypothesized that antibiotic pretreatment would diminish the number of cells infiltrating into the patch, potentially affecting early neointimal formation.

METHODS

Bovine pericardial patches were pretreated with saline, bacitracin (500 U/mL), or cephalexin (10 mg/mL) for 30 minutes before implantation into the Wistar rat infrarenal aorta. Patches were retrieved on day 7 or day 30 and analyzed for histology and cell infiltration. Markers of proliferation, apoptosis, vascular cell identity, and M1 and M2 macrophage subtypes were examined using immunofluorescence and immunohistochemistry. Extracted proteins were analyzed by Western blot.

RESULTS

At day 7, pericardial patches pretreated with bacitracin or cephalexin showed similar amounts of neointimal thickening (P = .55) and cellular infiltration (P = .42) compared with control patches. Patches pretreated with antibiotics showed similar proliferation (P = .09) and apoptosis (P = .84) as control patches. The cell composition of the neointima in pretreated patches was similar to control patches, with a thin endothelial layer overlying a thin layer of smooth muscle cells (P = .45), and containing similar numbers of CD34-positive (P = .26) and vascular endothelial growth factor receptor 2-positive (P = .31) cells. Interestingly, within the body of the patch, there were fewer macrophages (P = .0003) and a trend towards fewer endothelial progenitor cells (P = .051). No M1 macrophages were found in or around any of the patches. M2 macrophages were present around the patches, and there was no difference in numbers of M2 macrophages surrounding control patches and patches pretreated with antibiotics (P = .24). There was no difference in neointimal thickness at day 30 between control patches and patches pretreated with antibiotics (P = .52).

CONCLUSIONS

Pretreatment of bovine pericardial patches with the antibiotics bacitracin or cephalexin has no detrimental effect on early patch healing, with similar neointimal thickness, cellular infiltration, and numbers of M2 macrophages compared with control patches. These results suggest that the host vessel response to patch angioplasty using pericardial patches is adaptive remodeling (eg, arterial healing).

Hemodynamically motivated choice of patch angioplasty for the performance of carotid endarterectomy

Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of materials are available, but little is known to aid the surgeon in choosing a patch while caring for a patient with carotid disease. The objective of this study was to investigate biomechanics of the carotid artery (CA) repaired with patch angioplasty, study the influence of patch width and location of closure on hemodynamics, and to select the optimal patch material from those commonly used. For this purpose, a mathematical model was built that accounts for fluid-structure interaction, three-dimensional arterial geometry, non-linear anisotropic mechanical properties, non-Newtonian flow and in vivo boundary conditions. This model was used to study disease-related mechanical factors in the arterial wall and blood flow for different types of patch angioplasty. Analysis indicated that patch closures performed with autologous vein and bovine pericardium were hemodynamically superior to carotid endarterectomy with synthetic patch angioplasty (polytetrafluoroethylene, Dacron) in terms of restenosis potential. Width of the patch and location of arteriotomy were found to be of paramount importance, with narrow patches being superior to wide patches, and anterior arteriotomy being superior to the lateral arteriotomy. These data can aid vascular surgeons in their selection of patch angioplasty technique and material for the care of patients undergoing open CA repair.

Systematic review of randomized controlled trials of different types of patch materials during carotid endarterectomy

Background and Purpose

Carotid endarterectomy (CEA) with patch angioplasty produces greater results than with primary closure; however, there remains uncertainty on the optimal patch material in CEA. A systematic review of randomized controlled trials (RCTs) was performed to evaluate the effect of angioplasty using venous patch versus synthetic patch material, and Dacron patch versus polytetrafluoroethelene (PTFE) patch material during CEA.

Methods

A multiple electronic health database screening was performed including the Cochrane library, Pubmed, Ovid, EMBASE and Google Scholar on all randomized controlled trials (RCTs) published before November 2012 that compared the outcomes of patients undergoing CEA with venous patch versus synthetic patch. RCTs were included if they compared carotid patch angioplasty with autologus venous patch versus synthetic patch material, or compared one type of synthetic patch with another.

Results

Thirteen RCTs were identified. Ten trials, involving 1946 CEAs, compared venous patch with synthetic patch materials. Two trials, involving 400 CEAs in 380 patients, compared Dacron patch with PTFE patch. The hemostasis time in CEA with PTFE patch was significantly longer than with venous patch (P<0.0001), and longer than with Dacron patch (P<0.0001). There was no significant difference of mortality rate, stroke rate, restenosis, and operative time in CEA with venous patch versus synthetic patch material, or in CEA with Dacron patch versus PTFE patch (all P>0.05). One RCT of 95 CEAs in 92 patients compared bovine pericardium with Dacron patch, and demonstrated a statistically significant decrease in intraoperative suture line bleeding with bovine pericardium compared with Dacron patch (P<0.001).

Conclusions

The hemostasis time in CEA with PTFE patch was longer than with venous patch or Dacron patch. The overall perioperative and long-term mortality rate, stroke rate, restenosis, and operative time were similar when using venous patch versus synthetic patch material or Dacron patch versus PTFE patch material during CEA. More data are required to clarify differences between different patch materials.

Comparative analysis of the biaxial mechanical behavior of carotid wall tissue and biological and synthetic materials used for carotid patch angioplasty

Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of patching materials are available for use while new materials are being continuously developed. Surprisingly little is known about the mechanical properties of these materials and how these properties compare with those of the carotid artery wall. Mismatch of the mechanical properties can produce mechanical and hemodynamic effects that may compromise the long-term patency of the endarterectomized arterial segment. The aim of this paper was to systematically evaluate and compare the biaxial mechanical behavior of the most commonly used patching materials. We compared PTFE (n  =  1), Dacron (n  =  2), bovine pericardium (n  =  10), autogenous greater saphenous vein (n  =  10), and autogenous external jugular vein (n  =  9) with the wall of the common carotid artery (n  =  18). All patching materials were found to be significantly stiffer than the carotid wall in both the longitudinal and circumferential directions. Synthetic patches demonstrated the most mismatch in stiffness values and vein patches the least mismatch in stiffness values compared to those of the native carotid artery. All biological materials, including the carotid artery, demonstrated substantial nonlinearity, anisotropy, and variability; however, the behavior of biological and biologically-derived patches was both qualitatively and quantitatively different from the behavior of the carotid wall. The majority of carotid arteries tested were stiffer in the circumferential direction, while the opposite anisotropy was observed for all types of vein patches and bovine pericardium. The rates of increase in the nonlinear stiffness over the physiological stress range were also different for the carotid and patching materials. Several carotid wall samples exhibited reverse anisotropy compared to the average behavior of the carotid tissue. A similar characteristic was observed for two of 19 vein patches. The obtained results quantify, for the first time, significant mechanical dissimilarity of the currently available patching materials and the carotid artery. The results can be used as guidance for designing more efficient patches with mechanical properties resembling those of the carotid wall. The presented systematic comparative mechanical analysis of the existing patching materials provides valuable information for patch selection in the daily practice of carotid surgery and can be used in future clinical studies comparing the efficacy of different patches in the performance of carotid endarterectomy.

Clinical, anatomic, and procedural durability of carotid revascularization

Carotid endarterectomy and carotid angioplasty with stenting are 2 common approaches to revascularization. Phase III randomized clinical trials have focused on comparisons of periprocedural outcomes and composite outcomes that combine procedural events and clinical events during follow-up. The comparison of outcomes beyond the perioperative risk period, where the principal concern is durability, defined in clinical, anatomic, and procedural terms, has received less attention. The purpose of this review is to discuss factors that may influence durability and to compare the durability of carotid revascularization techniques beyond the perioperative period using data from randomized clinical trials.

Systematic review of randomized controlled trials of patch angioplasty versus primary closure and different types of patch materials during carotid endarterectomy

OBJECTIVE

Patch angioplasty during carotid endarterectomy (CEA) can reduce the risk of perioperative stroke or late carotid artery recurrent stenosis and subsequent ischaemic stroke. We aimed to update our previous systematic review of randomized controlled trials (RCTs) of routine or selective carotid patch angioplasty compared with CEA with primary closure, and of different materials used for carotid patch angioplasty.

METHODS

We identified new RCTs published during 2002-2010 by searching Medline, Embase and the Cochrane Stroke Group Trials Register. We also hand-searched six relevant journals. Pooled estimates of treatment effects combined with our previous review (1966-2001) were calculated on the basis of a weighted estimate of the odds ratio (OR) with the Peto method.

RESULTS

Twenty-three eligible RCTs were identified in both periods. Ten RCTs involving 2,157 operations compared primary closure with routine patch closure. Patch closure significantly reduced the combined risk of perioperative stroke and later stroke during long-term follow-up [OR = 0.49, 95% confidence interval (CI) = 0.27-0.90, p = 0.001; 7 RCTs]. Patching also reduced the risks of perioperative arterial occlusion (OR = 0.18, 95% CI = 0.08-0.41, p < 0.0001; 7 RCTs) and recurrent stenosis during long-term followup (OR = 0.24, 95% CI = 0.17-0.34, p < 0.001; 8 RCTs).

CONCLUSION

Meta-analysis of relatively small RCTs suggests that carotid patch angioplasty reduces the combined perioperative and long-term risk of stroke and the risk of restenosis. More data are needed.

Patches of different types for carotid patch angioplasty

BACKGROUND

Carotid patches for carotid endarterectomy may be made from an autologous vein or synthetic material.

OBJECTIVES

To assess the safety and efficacy of different materials for carotid patch angioplasty.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register (last searched 3 August 2009), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2009), MEDLINE (1966 to November 2008), EMBASE (1980 to November 2008) and Index to Scientific and Technical Proceedings (1980 to 2008). We handsearched relevant journals and conference proceedings, checked reference lists, and contacted experts in the field.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing one type of carotid patch with another for carotid endarterectomy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility, trial quality, and extracted data.

MAIN RESULTS

We included 13 trials involving a total of 2083 operations; seven trials compared vein closure with PTFE closure, and six compared Dacron grafts with other synthetic materials. In most trials a patient could be randomised twice and have each carotid artery randomised to different treatment groups. There were no significant differences in the outcomes between vein patches and synthetic materials apart from pseudoaneurysms where there were fewer associated with synthetic patches than vein patches (odds ratio (OR) 0.09, 95% confidence interval (CI) 0.02 to 0.49). However, the numbers involved were small and the clinical significance of this finding is uncertain. Compared to other synthetic patches, Dacron was associated with a higher risk of: perioperative combined stroke and transient ischaemic attack (P = 0.03); restenosis at 30 days (P = 0.004); perioperative stroke (P = 0.07) and perioperative carotid thrombosis (P = 0.1). During follow-up for more than one year, there were also significantly more strokes (P = 0.03), stroke/death (P = 0.02) and arterial restenoses (P < 0.0001) with Dacron but the numbers of outcomes were small and the significance of this finding is uncertain.

AUTHORS' CONCLUSIONS

The number of outcome events is too small to allow reliable conclusions to be drawn and more trial data are required to establish whether any differences do exist. Nevertheless, there is some evidence that other synthetic (e.g. PTFE) patches may be superior to collagen impregnated Dacron grafts in terms of perioperative stroke rates and restenosis. Pseudoaneurysm formation may be more common after use of a vein patch compared with a synthetic patch.

Patches for carotid artery endarterectomy: current materials and prospects

Patch angioplasty is commonly performed after carotid endarterectomy. Randomized prospective trials and meta-analyses have documented improved rates of perioperative and long-term stroke prevention as well as reduced rates of restenosis for patches compared with primary closure of the arteriotomy. Although use of vein patches is considered to be the gold standard for patch closure, newer generations of synthetic and biologic materials rival outcomes associated with vein patches. Future bioengineered patches are likely to optimize patch performance, both by achieving minimal stroke risk and long-term rates of restenosis as well as by minimizing the risk of unusual complications of prosthetic patches such as infection and pseudoaneurysm formation. In addition, lessons from bioengineered patches will likely enable construction of bioengineered and tissue-engineered bypass grafts.

Primary closure, routine patching, and eversion endarterectomy: what is the current state of the literature supporting use of these techniques?

Our objective in this article was to review the most recent literature on the status of carotid patching or primary carotid closure following carotid endarterectomy; to determine the best patch material if needed; and to clarify the place of eversion carotid endarterectomy in management of carotid artery atherosclerosis. In order to accomplish this, a literature review was performed of the Ovid, PubMed and MedLine databases using appropriate search terms. An evidence-based approach was taken; with all articles graded using the Scottish Intercollegiate Guidelines Network system (levels of evidence 1 to 5) and recommendations were made using an A to D system. Most weight was given to well-conducted, adequately powered, randomized control trials. After review of the literature, we were able to make the following Grade A recommendation: carotid patching is superior to primary closure, resulting in fewer postoperative strokes and a lower incidence of restenosis in most surgeons' hands. However, it was also concluded that, based on review of the literature, that the choice of patch material in 2007 has little impact; eversion carotid endarterectomy (CEA) and conventional patch CEA have equivalent postoperative morbidity and similar incidences of long-term restenosis. In conclusion, the technique of CEA continues to evolve, but in most reported series, immediate and long-term outcomes are excellent. A variety of technical approaches are acceptable, but it appears that carotid patching remains superior to primary closure.

Carotid endarterectomy for stroke prevention revisited

Since its original description, more than 50 years ago, carotid endarterectomy (CEA) has been challenged in its success in achieving adequate stroke prevention among both symptomatic and asymptomatic patients with cervical carotid stenosis. CEA remains the most common vascular surgical operation performed today, however, its future has been called into question with the introduction of percutaneous carotid angioplasty and stenting, more effective antiplatelet agents (i.e., clopidogrel), cholesterol-lowering agents (i.e., statins) and angiotensin-converting enzyme inhibitors. The focus of this article is to review the notable trials substantiating the efficacy of CEA, indications for surgery and technical components that have refined expected favorable outcomes.

A randomized trial of synthetic patch versus direct primary closure in carotid endarterectomy

OBJECTIVE

To define whether or not direct microscopic closure with or without the use of a vascular patch is advantageous in terms of clinical outcome and late vessel occlusion rates after microsurgical carotid endarterectomy.

METHODS

Three hundred thirty-eight elective carotid endarterectomies in 315 patients were randomized to direct arteriotomy or closure with a polyester collagen-coated vascular patch. Ten procedures did not follow the randomization process because of technical difficulties and were excluded. Vessel patency (duplex ultrasound) and outcome were assessed during and immediately after surgery and at 4 and 12 months after surgery.

RESULTS

Four-month ultrasound assessment (n = 321) identified five occluded vessels: two in the patch group (n = 149) and three in the direct closure group (n = 172). Six patients in the patch group had died or were significantly disabled at 4 months, compared with five in the direct closure group. At the 12-month assessment (n = 313), eight vessels had occluded: five from the patched group (n = 146) and three from the direct closure group (n = 167). Eight patients in the patch group had died or were significantly disabled, compared with four in the direct closure group. No statistically significant difference between the two groups in terms of vessel occlusion, morbidity, or mortality was seen (P > 0.1).

CONCLUSION

No difference in vessel patency and clinical outcome has been identified after microscopic patch angioplasty and direct arteriotomy repair. The authors conclude that there is no benefit from the routine use of patch angioplasty in microscopic carotid endarterectomy.

Dacron Patch Infection after Carotid Endarterectomy: Case Report and Review of the Literature

Patch angioplasty of the carotid artery after endarterectomy is a widely utilized technique with potential benefits of perioperative and long-term stroke risk reduction as well as a decreased incidence of recurrent stenosis. One of the complications of using a synthetic material as a patch is the development of prosthetic patch infection. We present a case report of a patient who was treated at our institution with such a complication and review the literature on this rare occurrence. The risk factors, workup, diagnosis, and treatment of prosthetic patch infection are reviewed. Despite the serious nature of this problem, surgical treatment is associated with minimal morbidity and an acceptable postoperative mortality and stroke rate.

A personal experience with coronary artery bypass grafting, carotid patching, and other factors influencing the outcome of carotid endarterectomy

OBJECTIVE

This study was conducted to investigate the influence of coronary artery bypass grafting (CABG), carotid patching, and other factors on the outcome of all carotid endarterectomies (CEAs) performed by a single surgeon at a tertiary referral center.

METHODS

The series includes 2262 CEAs (335 bilateral) in 1521 men and 741 women (33%) with median ages of 66 and 68 years, respectively. Surgical indications were asymptomatic stenosis for 1503 procedures (66%), retinal ischemia or cerebral transient ischemic attacks each for 271 (12%), and prior stroke for 217 (9.6%). CEA was done as an isolated operation in 1959 patients and was performed in conjunction with simultaneous CABG in 303 (13%). Primary arteriotomy closure was used for 783 CEAs (35%), vein patching for 1232 (54%), and synthetic patching for 247 (11%). Outcome event rates were assessed by logistic regression analysis, proportional hazards models, and Kaplan-Meier estimations.

RESULTS

Postoperative mortality (odds ratio [OR], 3.5; 95% confidence interval [CI], 1.7 to 7.5; P = .001), stroke (OR, 3.2; 95% CI, 1.6 to 6.4; P = .001), and combined stroke and mortality rates (OR, 3.4; 95% CI, 2.0 to 5.8; P < .001) were significantly higher for simultaneous CEA/CABG than for isolated CEA. Ipsilateral postoperative stroke rates were similar (2.6% vs 1.7%, P = .41) in both settings. Vein patching had a lower risk for ipsilateral stroke (OR, 0.42; 95% CI, 0.21 to 0.86; P = .015) than primary closure, but was not significantly different from synthetic patching (P = .10). The documented incidence of postoperative carotid thrombosis was 1.5% with primary closure, 0.6% with vein patching, and 2.0% with synthetic patching (P = .088). Overall Kaplan-Meier survival was 92% at 1 year, 71% at 5 years, 41% at 10 years, and 20% at 15 years, but long-term mortality rates were higher after simultaneous CEA/CABG (hazard ratio, 1.3; 95% CI, 1.1 to 1.5; P = .002) than after CEA alone. Late strokes or retinal infarctions have been reported after 97 (5.0%) of the 1923 operations for which follow-up was available, 51 (2.3%) of which were ipsilateral to CEA. The incidence of > or = 60% recurrent stenosis was independently influenced by carotid patching (OR, 0.61; 95% CI, 0.40 to 0.92; P = .019) but not by the choice of patch material (P = .11).

CONCLUSIONS

These results substantiate the common observation that patients who require simultaneous CEA/CABG have a higher risk for adverse outcomes than patients who undergo isolated CEA. Carotid patching provided significant benefit with respect to the risks for ipsilateral postoperative stroke and > or = 60% recurrent stenosis.

Primary closure of the carotid artery is associated with poorer outcomes during carotid endarterectomy

INTRODUCTION

Arterial endarterectomy and reconstruction during carotid endarterectomy (CEA) can be performed in a variety of ways, including standard endarterectomy with primary closure, standard endarterectomy with patch angioplasty, and eversion endarterectomy. The optimal method of arterial reconstruction remains a matter of controversy. The objective of this study was to determine the effect of the method of arterial reconstruction during CEA on perioperative outcome.

METHODS

A retrospective cohort study of consecutive CEAs performed by 81 surgeons during 1997 and 1998 in six regional hospitals was performed. Detailed clinical data regarding each case and all deaths and nonfatal strokes within 30 days of surgery were ascertained by an independent review of the inpatient chart, outpatient surgeon record, and the hospitals' administrative databases. Two physician investigators--one neurologist and one internist--confirmed each adverse event by independently reviewing patients' medical records.

RESULTS

A total of 1972 CEAs were performed. The mean age of the patients was 72.3 years, and 57.2% were male. Preoperative neurologic symptoms occurred in 28.7% of cases (n = 566), and the remaining 71.3% were asymptomatic before surgery (n = 1406). The method of arterial reconstruction was chosen by the surgeon. Primary closure was performed in 11.8% (n = 233), patch angioplasty in 69.8% (n = 1377), and eversion endarterectomy in 18.4% (n = 362). There was no significant difference in the preoperative symptom status of patients who underwent primary closure compared with the other methods of reconstruction (72.5% asymptomatic vs 71.1%, p = NS). Primary closure cases were significantly more likely to experience perioperative stroke compared with the other closure techniques (5.6% vs 2.2%, P = .006). Primary closure cases also had a higher incidence of perioperative stroke or death compared with the other closure techniques (6.0% vs 2.5%, P = .006). There were no significant differences with regard to either perioperative stroke, or perioperative stroke/death noted when comparing patch angioplasty with eversion endarterectomy: stroke, 2.2% vs 2.5% (P = NS) and stroke/death, 2.5% vs 2.5% (P = NS) respectively.

CONCLUSION

It appears that primary closure is associated with significantly worse perioperative outcomes compared with endarterectomy with patch angioplasty and eversion endarterectomy, even when the preoperative symptom status of the patient cohorts is equivalent. Although some of its advocates have reported that they can properly select appropriate patients for primary closure based on the size of the artery and other factors, the data demonstrate that these patients have poorer outcomes nonetheless. Primary closure during carotid endarterectomy should predominantly be abandoned in favor of either standard endarterectomy with patch angioplasty or eversion endarterectomy.

Prospective study of carotid endarterectomy with modified polytetrafluoroethylene (ACUSEAL) patching: Early and late results

OBJECTIVE

Carotid endarterectomies (CEAs) with standard polytetrafluoroethylene (PTFE) patching have been shown to have results comparable with those of autogenous vein patching; however, prolonged bleeding through needle holes in PTFE is a commonly recognized problem. This is the first study of CEA using a new hemostatic modified PTFE patch (GORE-TEX) analyzing the early and late outcomes.

METHODS

Two hundred consecutive CEAs were entered into this protocol. All patients had an immediate postoperative carotid duplex ultrasound scan that was repeated at 1 month and every 6 to 12 months thereafter. A Kaplan-Meier analysis was used to estimate the stroke-free survival and the risk of restenosis. The mean follow-up was 21 months (range, 1 to 48 months).

RESULTS

The perioperative stroke rate was 1.5% (1% ipsilateral and 0.5% contralateral, two minor strokes and one major stroke) with no perioperative mortality or perioperative carotid thrombosis. The incidence of perioperative transient ischemic attacks was 3.5% (2.5% ipsilateral and 1% contralateral). The mean hemostasis time after completion of the patching was 3 minutes, in contrast to 14 minutes for conventional PTFE (in a previous study). The rates of freedom from ipsilateral strokes at 1, 2, 3, and 4 years were 99%, 99%, 99%, and 99%, respectively. The cumulative stroke-free survival rates at 1, 2, 3, and 4 years were 98%, 96%, 93%, and 93%, respectively. The rates of freedom from > or =70% restenosis at 1, 2, 3, and 4 years were 97%, 97%, 94%, and 94%, respectively.

CONCLUSIONS

CEAs with a new modified PTFE patch are safe, have low perioperative stroke rates, are durable, and have an acceptable hemostasis time.

Systematic review of randomized controlled trials of patch angioplasty versus primary closure and different types of patch materials during carotid endarterectomy

BACKGROUND

Patch angioplasty during carotid endarterectomy (CEA) may reduce the risk for perioperative or late carotid artery recurrent stenosis and subsequent ischemic stroke. We performed a systematic review of randomized controlled trials to assess the effect of routine or selective carotid patch angioplasty compared with CEA with primary closure, and the effect of different materials used for carotid patch angioplasty.

METHODS

Randomized trials were included if they compared carotid patch angioplasty with primary closure in any patients undergoing CEA or use of one type of carotid patch with another.

RESULTS

Thirteen eligible randomized trials were identified. Seven trials involving 1281 operations compared primary closure with routine patch closure, and 8 trials with 1480 operations compared different patch materials (2 studies compared both). Patch angioplasty was associated with a reduction in risk for stroke of any type (P = .004), ipsilateral stroke (P = .001), and stroke or death during both the perioperative period (P = .007) and long-term follow-up (P = .004). Patching was also associated with reduced risk for perioperative arterial occlusion (P = .0001) and decreased recurrent stenosis during long-term follow-up (P < .0001). Seven trials that compared different patch types showed no difference in the risk for stroke, death, or arterial recurrent stenosis either perioperatively or at 1-year follow-up. One study of 180 patients (200 arteries) compared collagen-impregnated Dacron (Hemashield) patches with polytetrafluoroethylene patches. There was a significant increase in risk for stroke (P = .02), combined stroke and transient ischemic attack (P = .03), and recurrent stenosis (P = .01) at 30 days, and an increased risk for late recurrent stenosis greater than 50% (P < .001) associated with Dacron compared with polytetrafluoroethylene.

CONCLUSIONS

Carotid patch angioplasty decreases the risk for perioperative death or stroke, and long-term risk for ipsilateral ischemic stroke. More data are required to establish differences between various patch materials.

Randomized trial of vein versus dacron patching during carotid endarterectomy: Long-term results

BACKGROUND AND PURPOSE

Overviews of randomized patch trials by the Cochrane Collaboration suggest that a policy of routine patching is preferable to routine primary closure. However, there is no systematic evidence that patch type, whether prosthetic or vein, influences outcome after carotid endarterectomy (CEA).

METHODS

Two hundred seventy-three patients were randomized to vein or thin-walled Dacron patch (Hemashield Finesse) closure of the arteriotomy after 276 CEA procedures. Patients were reviewed clinically and with duplex ultrasound scanning at 1, 6, 12, 24, and 36 months or until death. No patients were lost to follow-up. Cumulative statistical analyses are presented for the 264 patients (269 CEAs) who actually received a randomized treatment allocation.

RESULTS

Cumulative freedom from death or ipsilateral stroke at 3 years (including operative events) was 93.0% in the Dacron patch group and 95.5% in the vein group P =.42). Cumulative freedom from death or any stroke was 91.5% after Dacron patch closure and 93.9% after vein closure (P =.46). Cumulative freedom from recurrent stenosis greater than 70% or occlusion at 3 years was 92.9% for patients randomized to the Dacron patch group and 98.4% for patients randomized to the vein group (P =.03). At 3 years the incidence of stroke in the carotid territory not operated on was 1.0% in 93 patients with no contralateral internal carotid artery disease at randomization, and increased to 1.3% in 78 patients with 1% to 69% stenosis, and 2.0% in 51 patients with contralateral 70% to 99% stenosis. No late strokes occurred distal to 42 occluded contralateral internal carotid arteries.

CONCLUSIONS

Patch type has no influence on early operative risk, no association with enhanced patterns of thrombogenicity in the early postoperative period, and no influence on risk for ipsilateral or any stroke at 3 years. Dacron patches were, however, associated with a significantly higher incidence of recurrent stenosis at 3 years, with most occurring within 6 to 12 months of surgery. However, the higher incidence of recurrent stenosis was not associated with a parallel increase in late stroke, and in this study a program of serial ultrasound surveillance could not have prevented one ipsilateral stroke.

Patches of different types for carotid patch angioplasty

BACKGROUND

Some surgeons who use carotid patching favour using a patch made from an autologous vein, whilst others prefer to use synthetic materials.

OBJECTIVES

The objective of this review was to assess the safety and efficacy of different materials for carotid patch angioplasty.

SEARCH STRATEGY

We searched the Cochrane Stroke Group trials register (last searched November 2002). In addition, we searched the Cochrane Controlled Trials Register (The Cochrane Library, Issue 4, 2001), MEDLINE (1966 to December 2001), EMBASE (1980 to December 2001) and Index to Scientific and Technical Proceedings (1980 to 2001). We also handsearched eight journals and five conference proceedings. Reference lists were checked and we contacted experts in the field to identify further published and unpublished studies.

SELECTION CRITERIA

Randomised and quasi-randomised trials comparing one type of carotid patch with another for carotid endarterectomy.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed eligibility, trial quality, and extracted the data

MAIN RESULTS

The previous version of this review included three trials involving 326 operations. Since then a further five trials have been reported, increasing the number of operations to 1480. Prior to 1995, all studies had compared vein closure with PTFE closure, but three of the later studies compared vein to Dacron grafts instead and one compared Dacron with PTFE. Allocation was not adequately concealed in two trials, and one only followed up patients to the time of hospital discharge. Intention to treat analysis was possible for six trials. In all but two trials a patient could be randomised twice and have each carotid artery randomised to different treatment groups. There were too few operative events to determine whether there was any difference between the vein and Dacron patches for perioperative stroke, death and arterial complications. The one study that compared Dacron and PTFE patches found a significant risk of combined stroke and transient ischaemic attack (p = 0.03) and restenosis at 30 days (p = 0.01), a borderline significant risk of perioperative stroke (p = 0.06), and a non significant increased risk of perioperative carotid thrombosis (p = 0.1) with dacron compared with PTFE. Five trials followed up patients for longer than 30 days. During follow-up for more than one year, no difference was shown between the two types of patch for the risk of stroke, death, or arterial restenosis. However, the number of events was small. Based on 15 events in 776 patients in four trials, there were significantly fewer pseudoaneurysms associated with synthetic patches than vein (odds ratio [OR] 0.09, 95% confidence interval [CI] 0.02 to 0.49) but the numbers involved were small and the clinical significance of this finding is uncertain.

REVIEWERS' CONCLUSIONS

It is likely that the differences between different types of patch material are very small. Consequently, many more data than are currently available will be required to establish whether any differences do exist. Some evidence exists that PTFE patches may be superior to Colagen impregnated Dacron grafts in terms of perioperative stroke rates and restenosis. However the evidence is based upon data from a single, small trial and more studies that compare different types of synthetic graft are required to make firm conclusions. Psuedo aneurysm formation may be more common after use of a vein patch compared with a synthetic patch.

Carotid artery revascularization

Stroke is the third leading cause of death in the United States, and up to one third of patients have a stroke secondary to carotid occlusive disease. Surgical management has firmly established itself as an important modality in treating this disease. Several prospective randomized trials have defined the patients that would have the most benefit from carotid endarterectomy (CEA). These patient populations include asymptomatic patients with a >or= 60% stenosis and symptomatic patients with a >or= 50% stenosis. The timing of CEA after stroke remains controversial, but recent studies advocate early CEA in a select group of patients. During the CEA, the method of closing of the arteriotomy has an overall effect on the safety of the procedure as well as long-term outcome. As compared with primary repair of the arteriotomy, patch closure has been shown to decrease the frequency of restenosis. In addition, carotid eversion endarterectomy (CEE) is an alternative method to remove the plaque that has a similar efficacy to standard CEA. The role of carotid angioplasty and stenting (CAS) continues to evolve and offers the patient a less invasive method of treating the carotid plaque.

Prospective, randomized study of external jugular vein patch versus polytetrafluoroethylene patch during carotid endarterectomy: perioperative and long-term results

OBJECTIVES

The purpose of this study was to evaluate the relative risks and advantages of using external jugular vein (EJV) patch, compared with polytetrafluoroethylene (PTFE) patch, during carotid endarterectomy. The primary end point was the relevant neurologic complication rate (RNCR; fatal or disabling stroke) at any time during follow-up. Secondary end points included stroke-free survival, 30-day and long-term mortality, recurrent stenosis rate (> or =50%), occlusion, patch infection, aneurysm formation, and other local complications.

METHODS

The study, a prospective randomized clinical trial carried out at a single center, was divided into two 3-year phases: December 1996 to March 1999, when patients were enrolled, and March 1999 to March 2002, which was the follow-up period. Inclusion criteria included an external jugular vein suitable for patching, defined as vein diameter 3 mm or larger and absence of collateral vessels noted on preoperative color duplex ultrasound scans. Patients were prospectively randomized 1:1 to receive either the EJV (n = 80; group A) or synthetic (n = 80; group B) patch.

RESULTS

Carotid endarterectomy and patching was performed by one surgeon. At 30 months the RNCR-free rate, analyzed with the Kaplan-Meier method, was 98.7% for group A (1 ipsilateral lethal stroke) and 94.6% for group B (4 ipsilateral disabling strokes), and remained stable to 60 months. No statistical difference was observed with the log-rank test. Stroke-free survival rate was 100% for group A and 98.7% for group B at 1 year, 98.7% for group A and 93.6% for group B (1 ipsilateral minor stroke) at 30 months, and was unchanged at 60 months. Life table analysis demonstrated freedom from significant recurrent stenosis (> or =50%) of 97.5% for both groups at 6 months, 93.6% for group A and 92.2% for group B at 30 months, and 90.2% for group A and 86.7% for group B at 60 months. No statistical difference was observed with the log-rank test. In no patients was recurrent stenosis greater than 70%. No aneurysm formation was noted during follow-up.

CONCLUSIONS

We can conclude, with the power limitation of the study, that carotid endarterectomy can be safely performed with either the EJV or PTFE patch. Advantages of the EJV for carotid angioplasty include no cost for material, low risk for graft infection, and preservation of the saphenous vein.

Postoperative infection associated with polyester patch angioplasty after carotid endarterectomy

OBJECTIVES

Postoperative infection is one of the most dreaded complications associated with use of synthetic patches for carotid endarterectomy. Although polyester patches were used extensively for carotid patch angioplasty throughout the last decade, few reports detail cases of deep patch infection. We describe our experience with polyester patch infections after carotid endarterectomy. Patients and methods From January 1996 through December 2001 we treated polyester patch infections after carotid endarterectomy in 10 patients.

RESULTS

The interval from primary carotid endarterectomy to presentation with infection ranged from 11 days to 30 months. All patients underwent repeat operation that involved tissue debridement, excision of the polyester patch, and either interposition grafting or patch angioplasty with autologous vein. No perioperative stroke or death occurred; however, 1 patient had transient hoarseness, and in 1 patient a pseudoaneurysm developed that required additional surgical repair with a saphenous vein interposition graft. All patients remain well and free of infection with follow-up as long as 56 months.

CONCLUSIONS

Infection is a serious and rare complication of carotid patch angioplasty with polyester material. Nonetheless, it can be treated successfully with good results and acceptable morbidity with soft tissue debridement, prosthetic patch excision, and either patch angioplasty or interposition grafting with autologous vein.