Patches for carotid artery endarterectomy: current materials and prospects

Contemporary open surgical approaches for the management of carotid stenosis: a comprehensive review

This study aims to provide an overview on contemporary open surgical approaches for the management of carotid artery stenosis. A comprehensive literature search was performed to identify and categorize open surgery intervention techniques for the management of carotid artery stenosis, focusing on the benefits and drawbacks of each technique. Five surgical techniques for carotid endarterectomy (CEA) have been described: CEA with primary closure, CEA with patch closure, CEA by eversion technique, CEA by modified eversion technique and CEA by partial eversion. Evidence has reported significantly higher rates of perioperative complications after CEA with primary closure, including 30-days stroke rate and late restenosis. Although more recent techniques have been reported to provide superior outcomes, electing the best surgical technique is still a matter of debate. Also, CEA using a mini-skin incision has been associated to lower risk of cranial/cervical nerve injury and shorter length of hospital stay. The selection of the surgical intervention should be tailored and have into consideration individual patient characteristics, clinical considerations, surgeon preference and surgical team expertise. Further large-scale randomized clinical trials are needed to support more robust decisions on the choice of contemporary open surgical approaches to manage carotid stenosis.

Drainage Pattern of Craniofacial Veins With Emphasis on its Influence on Facial Reconstruction Procedures

As the facial transplantation procedures are becoming more popular and frequent in recent years, for repairing facial trauma, variations in the veins of head and neck needs to be reported time and again. This study was undertaken to examine the course and drainage pattern of the facial vein and external jugular vein on this context and emphasize its surgical implications. The authors studied the head and neck region of 50 embalmed cadavers of both sexes to document normal and variant anatomy of facial, retromandibular, and external jugular veins. In 30% of the head and neck regions, different draining pattern of the above-mentioned veins were observed. One of the rare variation discovered was the splitting of the retromandibular vein to embrace the external carotid artery within the parotid gland. The data about variations in the termination of facial vein, retromandibular vein, and external jugular vein, as observed in the present study might be useful in avoiding accidental injury to these vessels during any surgical intervention in the face as well as neck. Level of Evidence: IV.

Investigation of Combined Carotid Endarterectomy and Coronary Artery Bypass Graft Surgery Outcomes and Adverse Event Risk Factors in the Vascular Quality Initiative

OBJECTIVE

The purpose of this study was to investigate outcomes of simultaneous CEA and CABG utilizing the Vascular Quality Initiative (VQI). Additionally, we seek to investigate risks for both perioperative and long-term mortality and adverse neurological outcomes.

METHODS

All carotid endarterectomies in the VQI between January 2003 and May 2022 were queried. We identified 171,816 CEA in the database. We extracted 2 cohorts from these CEA. The first group was patients who underwent simultaneous carotid endarterectomy (CEA) and coronary artery bypass (CABG) (N = 3137). The second group encompassed patients who underwent CABG or percutaneous coronary artery angioplasty/stent within 5 years of ultimately undergoing CEA (N = 27,387). We investigated the following outcomes in a multivariable fashion: 1. Risks for mortality in long term follow-up for both cohorts combined; 2. Risks for ischemic event in the cerebral hemisphere ipsilateral to the CEA site after index hospital admission in follow up for both cohorts combined. Tertiary outcomes are also investigated in the manuscript.

RESULTS

On multivariable analysis, patients undergoing simultaneous combined CEA and CABG had equivalent long-term survival to patients who underwent coronary revascularization within 5 years of ultimately undergoing CEA. Five-year survival is noted to be 84.5% vs 86% with a Cox regression non-significant P-value (.203). Significant multivariable risks for reduced long term survival (P < .03 for all) included: advancing age (HR 2.48/year); smoking history (HR 1.26); Diabetes (HR 1.33); history of CHF (HR 1.66); history of COPD (HR 1.54); baseline renal insufficiency at the time of surgery (HR 1.30); anemia (HR1.64); lack of preoperative aspirin (HR 1.12); and lack of preoperative statin (HR 1.32); lack of patch placement at CEA site (HR 1.16); perioperative MI (HR 2.04); perioperative CHF (1.66); perioperative dysrhythmia (HR 1.36); cerebral reperfusion injury (HR 2.23); perioperative ischemic neurological event (HR 2.48); and lack of statin at discharge (HR 2.04). Amongst patients with documented neurological status in follow up, combined CEA and CABG had over 99% freedom from ischemic cerebral event ipsilateral to the CEA site after discharge.

CONCLUSIONS

Combined CEA and CABG provides excellent long-term mortality prevention in patients with co-existing severe coronary and carotid atherosclerosis. Simultaneous CEA and CABG provides equivalent stroke prevention and long-term survival to both a cohort of patients undergoing coronary revascularization within 5 years of CEA and patients undergoing isolated CEA or CABG in the literature. The two most impactful modifiable risk factors towards long-term stroke and mortality prevention for patients undergoing simultaneous CEA-CABG are patch placement at CEA site and adherence to statin medication therapy.

Outcomes of vein reconstruction using bovine pericardial patch

BACKGROUND

The bovine pericardium is a good alternative material to the autogenous vein in vascular reconstruction. This study aimed to evaluate the results of angioplasty in venous reconstruction using bovine pericardium and identify the risk factors for significant complications.

MATERIAL AND METHODS

A retrospective review was performed of the demographic data, clinical characteristics, and complications of patients who underwent vessel repair using bovine pericardium between February 2012 and December 2020. Univariate analysis was used to compare complication frequencies within several categories.

RESULTS

There were 36 cases of patch angioplasty using bovine pericardium. The median age was 65 years; 61% of them were men. Of the 36 venous repairs, 31 (86.1%) were from cancer surgery and five (13.9%) were from iatrogenic injury. Patch shape was used in 27 cases (75.0%), while tube shape was used in nine cases (25.0%). The incidence of occlusion and partial thrombus was five (13.9%) and three (8.3%) cases, respectively. Of the nine tube-shaped angioplasties, four (44.4%) required reoperation due to early thrombosis (three cases) and hematoma (one case).

CONCLUSION

The use of a bovine pericardial patch in the reconstruction of a damaged vein from tumor invasion or iatrogenic injury is feasible. However, the complication rate of vessel patency remains substantial, especially in cases of iatrogenic injury or when a tube-shaped form is used for repair.

Progress in the application of patch materials in cardiovascular surgery

The cardiovascular patch, served as artificial graft materials to replace heart or vascular tissue defect, is still playing a key role in cardiovascular surgeries. The defects of traditional cardiovascular patch materials may determine its unsatisfactory long-term effect or fatal complications after surgery. Recent studies on many new materials (such as tissue engineered materials, three-dimensional printed materials, etc) are being developed. Patch materials have been widely used in clinical procedures of cardiovascular surgeries such as angioplasty, cardiac atrioventricular wall or atrioventricular septum repair, and valve replacement. The clinical demand for better cardiovascular patch materials is still urgent. However, the cardiovascular patch materials need to adapt to normal coagulation mechanism and durability, promote short-term endothelialization after surgery, and inhibit long-term postoperative intimal hyperplasia, its research and development process is relatively complicated. Understanding the characteristics of various cardiovascular patch materials and their application in cardiovascular surgeries is important for the selection of new clinical surgical materials and the development of cardiovascular patch materials.

Carotid endarterectomy with saphenous vein patch angioplasty: a single-center experience

BACKGROUND

When performing a conventional CEA it is recommended the use of patch angioplasty (PA), since previous meta-analyses have shown PA to be superior to primary closure (PRC) in terms of stroke and restenosis rates. Different materials patches can be employed although none of them has been proved to be superior. Although autologous veins are potentially more resistant to immediate thrombosis as well as infection, cons may be represented by patch rupture and late dilatation. Aim of this study is to evaluate immediate and long-term results of CEA with saphenous vein patch angioplasty (SVPA) in a single-center experience.

METHODS

A retrospective study was performed analyzing all patients undergoing CEA with SVPA at our institution from January 2012 to March 2020. CEA was performed in symptomatic patients with 50-99% carotid stenosis degree or asymptomatic patients with 70-99% stenosis degree. Exclusion criteria were critical limb ischemia, varicose disease, unavailability of saphenous veins, vein diameter <3.5 mm. All CEAs were performed under general anesthesia with routine shunting. Primary endpoints were perioperative stroke, death, carotid thrombosis and hematoma requiring surgery rates. Secondary endpoints included the rate of recurrent stenosis >70%, patch aneurysm/rupture/infection at follow-up.

RESULTS

Overall, 488 interventions were performed on 461 patients. Most patients were male (77.8%) with a mean age of 71.2±8.3 years. Thirty-day mortality and stroke rates were 0.4% and 1.2% respectively. Carotid thrombosis occurred in five patients (1%). Five patients (1%) developed a surgical site hematoma requiring surgical drainage. At a mean follow-up of 34.4±25.8 months 12 restenoses (2.5%) were detected. Five-year freedom from restenosis rate was 96.7%. Restenosis at follow-up was more frequent in patients who had contralateral carotid stenosis (P=0.019). Two patients (0.4%) developed carotid patch aneurysmal degeneration at a mean follow-up of 78.7 months. No infection nor patch disruption were detected.

CONCLUSIONS

CEA with SVPA resulted safe and effective in terms of early and late results. The perioperative complications rates we recorded were quite similar to those reported by other larger reviews and meta-analyses.

Patch angioplasty during carotid endarterectomy using different materials has similar clinical outcomes

OBJECTIVE

Patch angioplasty during carotid endarterectomy (CEA) is commonly used to treat carotid artery stenosis. However, the choice of which patch to use remains a matter of debate. Autologous venous material has disadvantages such as wound-related problems at the harvest site and a prolonged intervention time. These limitations can be bypassed when synthetic or biological patches are used. Both materials have been associated with divergent advantages and disadvantages. Therefore, the aim of our study was to compare the long-term follow-up outcomes in patients who underwent CEA and closure with either a bovine pericardial patch (BPP) or polyester patch.

METHODS

A retrospective cohort study was conducted including all patients who underwent primary CEA and closure with a BPP or a polyester patch between January 2010 and December 2020 at our tertiary referral center. In 2015, the BPP was introduced as an alternative for polyester. The primary outcome was the occurrence of transient ischemic attack (TIA) or cerebrovascular accident (CVA) during follow-up and secondary outcomes included restenosis, reintervention, all-cause mortality, and patch infection. Cox proportional hazard models were used and hazard ratios with 95% confidence intervals were used to predict these outcomes.

RESULTS

We included 417 CEA patients; 254 patients (61%) received a BPP and 163 received (39%) a polyester patch. The mean age was 70.2 ± 8.7 years and 67% were male. The median follow-up time was 15 months (range, 12-27 months) for BPP and 42 months (range, 16-60 months) for polyester (P < .001). Postoperative hematoma (≤30 days) was significantly lower in the BPP cohort (2% BPP vs 6% polyester; P = .047). No other significant differences on short-term outcomes were found. Univariable Cox regression analyses showed no significant differences between the effect estimates of polyester and BPP on TIA or CVA (P = .106), restenosis (P = .211), reintervention (P = .549), or all-cause mortality (P = .158). No significant differences were found after adjusting for confounders in the multivariable analyses: TIA or CVA (P = .939), restenosis (P = .057), reintervention (P = .193) and all-cause mortality (P = .742). Three patients with a polyester patch had patch infection compared with none of the patients in the group who received a BPP.

CONCLUSIONS

This large retrospective study showed comparable safety and durability of both BPP and polyester suggesting that both patch types can be safely applied for CEA with patch angioplasty. Patch infection was rare and was absent in the BPP group.

Selection criteria for patch angioplasty material in carotid endarterectomy

Background:

Carotid endarterectomy (CEA) with patch angioplasty has been favored due to its lower reoccurrence of restenosis compared to primary CEA. There are multiple types of patch angioplasty material available. However, selection of patch material is based on uncertain criteria. The aim of this study is to determine the ideal criteria for selecting the best patch material for CEA.

Methods:

We conducted a comprehensive literature search for studies that describe the ideal criteria for selecting patch material for CEA. We compiled all of the criteria mentioned into one table and selecting the criteria which were most frequently mentioned with a simple scoring system.

Results:

A total of 65 studies out of 784 studies were assessed for its full-text eligibility. Thus, we found 23 studies that were eligible for analysis. There are 22 ideal criteria that were mentioned in the analyzed studies. We grouped these criteria into physical characteristics, safety, contribution to hemodynamic, contribution in tissue healing, economic aspect, and ability to prevent postsurgical complication. We proposed 10 ideal criteria for guiding vascular surgeon in selecting the best patch angioplasty material.

Conclusion:

To this day, no material has been discovered which meets all ten criteria. This study’s proposed ideal criteria serve as the foundation for the creation of the best patch angioplasty material.

Five-year outcome of non-shunting and primary closure technique during carotid endarterectomy: a longitudinal cohort study

Objective

The long-term outcomes of primary carotid artery closure after carotid endarterectomy (CEA) have not been sufficiently studied. This prospective study was performed to analyze the 5-year outcomes of the non-shunting and primary arterial repair technique for CEA.

Methods

This study involved 150 patients who underwent CEA with the primary arterial closure technique without arterial shunting and completed 5 years of follow-up.

Results

The patients comprised 107 men and 43 women. The 30-day postoperative course was uneventful in 147 (98.0%) patients; however, cerebrovascular accidents occurred in 3 (2.0%) patients. With respect to the long-term results, most cases of restenosis at 5 years were <50%. Two patients developed asymptomatic total internal carotid artery occlusion. Eleven deaths occurred (mortality rate of 7.3%); one death (0.7%) occurred in the first 30 days.

Conclusion

Primary arteriotomy closure provides very good long-term patency. Routine use of patch closure is unnecessary.

DLC-Coated Ferroelectric Membranes as Vascular Patches: Physico-Chemical Properties and Biocompatibility

In this paper, the results on the fabrication of ferroelectric membranes as vascular patches with modified surfaces are presented. For the modification of a membrane surface contacting blood, DLC coating was deposited using the pulsed vacuum arc deposition technique. The physico-chemical properties and cytotoxicity of the membranes modified under various conditions were studied. It was found that DLC coatings do not affect membrane microstructure, preserving its crystal structure as well as its high strength and elongation. It was revealed that an increase in the capacitor storage voltage results in the rise in sp²- and sp-hybridized carbon concentration, which makes it possible to control the chemical structure and surface energy of the modified surface. The experiments with 3T3L1 fibroblasts showed no toxic effects of the materials extracts.

Experiences with pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension at multiple centers in Taiwan

BACKGROUND

Of the types of pulmonary hypertension, chronic thromboembolic pulmonary hypertension (CTEPH) may be cured through pulmonary endarterectomy (PEA). In this study, we investigated patient experiences with PEA for CTEPH treatment in Taiwan.

METHODS

We retrospectively reviewed the records of patients who underwent PEA in two medical centers between January 2005 and December 2019. We measured the following outcomes: in-hospital complications, improvements in cardiac function and exercise capacity, survival using Kaplan-Meier analysis after PEA.

RESULTS

Twenty-seven patients (female: 17) with a mean age of 52.6 years underwent PEA. Pre-operatively, most patients were New York Heart Association functional class (NYHA FC) III (n = 19) and IV (n = 7). The mean periods from the onset of symptoms to diagnosis and from diagnosis to operation were 22.6 and 22.3 months, respectively. After PEA, mean intubation time, and length of intensive care unit and hospital stay were 9, 11, and 20 days, respectively. Most patients' NYHA FCs improved to I (n = 15) and II (n = 10). The mean 6-min walk test (6MWT) result improved by 60.5%. The in-hospital mortality, mean follow-up period, and 5- and 10-year overall survival rates were 3.7%, 77.0 months, 96.3%, and 84.3%, respectively. Furthermore, 5- and 10-year disease-specific survival rates were both 96.3%.

CONCLUSION

When pre-operative and post-operative statuses were compared, we found a significant improvement in NYHA FC and 6MWT distance. Our study also found a lower in-hospital mortality rate compared to other published studies, except compared to the newer data provided by the University of California, San Diego group.

Ex Vivo and In Vivo Analysis of a Novel Porcine Aortic Patch for Vascular Reconstruction

(1) Background: The aim of the present study was the biocompatibility analysis of a novel xenogeneic vascular graft material (PAP) based on native collagen won from porcine aorta using the subcutaneous implantation model up to 120 days post implantationem. As a control, an already commercially available collagen-based vessel graft (XenoSure®) based on bovine pericardium was used. Another focus was to analyze the (ultra-) structure and the purification effort. (2) Methods: Established methodologies such as the histological material analysis and the conduct of the subcutaneous implantation model in Wistar rats were applied. Moreover, established methods combining histological, immunohistochemical, and histomorphometrical procedures were applied to analyze the tissue reactions to the vessel graft materials, including the induction of pro- and anti-inflammatory macrophages to test the immune response. (3) Results: The results showed that the PAP implants induced a special cellular infiltration and host tissue integration based on its three different parts based on the different layers of the donor tissue. Thereby, these material parts induced a vascularization pattern that branches to all parts of the graft and altogether a balanced immune tissue reaction in contrast to the control material. (4) Conclusions: PAP implants seemed to be advantageous in many aspects: (i) cellular infiltration and host tissue integration, (ii) vascularization pattern that branches to all parts of the graft, and (iii) balanced immune tissue reaction that can result in less scar tissue and enhanced integrative healing patterns. Moreover, the unique trans-implant vascularization can provide unprecedented anti-infection properties that can avoid material-related bacterial infections.

Experimental comparative assay of tensile resistance of greater saphenous vein from ankle and groin

Background

The great saphenous vein is used as patch material in several types of arterial reconstruction, including trauma and carotid and femoral endarterectomy. There have been reports of saphenous patch blowout, particularly of patches constructed with veins harvested from the ankle. There is a need for objective measurement of the resistance of saphenous vein tissues.

Objectives

To measure the tensile strength of the great saphenous vein harvested at the ankle and groin and analyze the correlation between diameter and tissue strength.

Methods

Venous samples were harvested during elective saphenous stripping in patients with symptomatic varicose veins. Only segments without reflux were included. Ten limbs from eight patients were studied, providing 20 samples in total. Venous segments were opened along their longitudinal axis and fitted to electronic traction assay equipment to obtain values for material maximum tension in kilograms-force per square centimeter (kgf/cm²; the maximum force resisted by the segment, divided by its cross-sectional area).

Results

The average maximum tension in the ankle saphenous vein group ranged from 74.02 to 190.10 kgf/cm² and from 13.53 to 69.45 kgf/cm2 in the groin saphenous vein group (p < 0.0001). The Pearson coefficient for the correlation between vein diameter and maximum tension was -0.852 (moderate to strong inverse correlation).

Conclusions

Ankle saphenous vein tissue from female patients operated for varicose veins has significantly higher resistance than saphenous vein tissue from the groin and there is an inverse relation between vein diameter and resistance of tissue from the same population.

Novel Biomaterial for Artery Patch in Swine Model With High-Fat Diet

Objective

We evaluated swine and bovine pulmonary visceral pleura (PVP) in artery patch-angioplasty in swine model of high-fat diet.

Background

Arterial patch-angioplasty is frequently used for repair or reconstruction of arteries. An autologous patch is often limited by the number and dimension of donor tissue and can result in donor complications. Furthermore, mechanical mismatch is a cause of poor performance of vascular reconstruction. Here, we introduce a readily available patch biomaterial with similar compliance as native arteries.

Methods

The PVP was peeled from swine and bovine lungs by hydro-dissection. The swine and bovine PVPs were crosslinked with glutaraldehyde and then sterilized. The swine PVP (sPVP) patches were implanted in the carotid and femoral arteries of six Yorkshire pigs that were fed a regular diet and euthanized at 2 and 4 months postoperative. The bovine PVP (bPVP) patches were implanted in the carotid artery of six Yucatan pigs that were fed a high-fat diet and euthanized at 4 months postoperative. Patency was evaluated by ultrasound and angiography. Neo-endothelium and media were evaluated by histologic examination.

Results

All arteries in patch-angioplasties remained patent with no adhesions, inflammation, or aneurysms. Biomarkers of endothelial cells (e.g., Factor VIII and eNOS) were detected in the neo-endothelial cells. We observed endothelial cell–cell junctions in the confluent neo-endothelium in the PVP patches. Neo-media composed of vascular smooth muscle developed similar as native arteries. In the hypercholesterolemic model, we observed the accumulation of cholesterol in both arterial tissues and in the neo-vascular tissues in the PVP patches. Protein expressions of lipid transport and metabolism (e.g., APOE-1, ABCA, and PACK9) were also observed in both arterial and neo-vascular tissues.

Conclusion

The PVP patch-angioplasty overcomes the pitfalls of compliance mismatch of synthetic patches and has a non-thrombogenic surface. The proliferation of vascular cells assembled to generate the neo-endothelium and media in the patch-angioplasties to support long-term patency. The neo-vascular tissue in PVP patch-angioplasty also developed similar cellular functions for lipid transport and metabolism compared with native arteries in hypercholesterolemia.

The Use of Bovine Pericardial Patches in Vascular Surgery: Where do we Draw the Line in Obtaining Informed Consent?

For a patient undergoing a carotid endarterectomy, induction with propofol, administration of heparin at the time of vessel clamping, use of a bovine pericardial patch for angioplasty, covering the wound with a hydrocolloid dressing and post-operative aspirin administration exposes the patient to animal products at every stage, from the moment they walk through the door. A number of articles have advocated obtaining informed consent when using animal products in healthcare but where should the line be drawn?

METHODS

A narrative review of the literature, specifically focussing on secular and religious beliefs about the use of animal products in healthcare. Application of ethical principles and GMC guidance to formulatea discussion with regards to the use of bovine pericardium in vascular surgery. Advanced literature search carried out using Pubmed and Google Scholar databases comparing patch material used forcarotid endarterectomy.

RESULTS

Disclosing the use of animal derived constituents in surgery is warranted under Beauchamp and Childress' four principals and highlighted in GMC guidance. Obtaining consent for the use of animalderived constituents at the time of surgery is something that should become a fundamental component of the written consent process and alternatives should be sought where available and practicable.

CONCLUSION

This review highlights the evidence available and discusses our current standpoint from both a legal and ethical aspect.

In vivo endothelialization and neointimal hyperplasia assessment after rabbit carotid endarterectomy with bovine pericardium

Background

Previous studies have reported that the use of a patch in carotid endarterectomy (CEA) surgery can reduce the rate of restenosis and perioperative complications. The goal of this study was to compare the short- and medium-term outcomes of endothelialization and neointimal hyperplasia of patch closure (PC) angioplasty in CEA with direct closure (DC) in a rabbit model. A bovine pericardial patch (BPP) was used in the PC procedures.

Methods

Two carotid arteries were dried by air flow to simulate endarterectomy and selected for PC and DC in each rabbit. Different animals were sacrificed at 1, 2, 3, 4, and 8 weeks after the procedure. The endarterectomized segments were extracted and examined microscopically with histopathological and immunohistochemical analysis, and electron-microscopy measurements.

Results

In all, 19 rabbits were included in this study; 3 rabbits were placed in a 2-week postoperative group and 4 rabbits were placed in the 1-, 3-, 4-, and 8-week postoperative group respectively. Hematoxylin-eosin (HE) staining showed neointima on the PC side at an early stage (1-week postoperatively), and intimal hyperplasia could be seen on both sides. Immunohistochemical analysis showed that Ki-67 was higher on the PC side than on the DC side at an early stage (1,661.5±1,122.9 cells/mm², P=0.060). In the 2-week postoperative group, von Willebrand factor (vWF) was higher on the DC side (−377.0±155.6 cells/mm², P=0.052). Alpha-smooth muscle actin (α-SMA) values were comparable on both sides (P>0.05). Electron microscopy measurements showed that functional endothelial cells exhibited a cobblestone-like morphology and were nicely elongated in the direction of blood flow.

Conclusions

The use of BPP in PC angioplasty during CEA can maintain stability and also provide rapid endothelialization. PC with BPP has comparable ability of efficient endothelialization with DC, but is more likely to have early endothelialization.

Extracellular Matrix Patches for Endarterectomy Repair

Patch repair is the preferred method for arteriotomy closure following femoral or carotid endarterectomy. Choosing among available patch options remains a clinical challenge, as current evidence suggests roughly comparable outcomes between autologous grafts and synthetic and biologic materials. Biologic patches have potential advantages over other materials, including reduced risk for infection, mitigation of an excessive foreign body response, and the potential to remodel into healthy, vascularized tissue. Here we review the use of decellularized extracellular matrix (ECM) for cardiovascular applications, particularly endarterectomy repair, and the capacity of these materials to remodel into native, site-appropriate tissues. Also presented are data from two post-market observational studies of patients undergoing iliofemoral and carotid endarterectomy patch repair as well as one histologic case report in a challenging iliofemoral endarterectomy repair, all with the use of small intestine submucosa (SIS)-ECM. In alignment with previously reported studies, high patency was maintained, and adverse event rates were comparable to previously reported rates of patch angioplasty. Histologic analysis from one case identified constructive remodeling of the SIS-ECM, consistent with the histologic characteristics of the endarterectomized vessel. These clinical and histologic results align with the biologic potential described in the academic ECM literature. To our knowledge, this is the first histologic demonstration of SIS-ECM remodeling into site-appropriate vascular tissues following endarterectomy. Together, these findings support the safety and efficacy of SIS-ECM for patch repair of femoral and carotid arteriotomy.

Real-world experience of suture-based closure devices: Insights from the FDA Manufacturer and User Facility Device Experience

OBJECTIVES

We analyzed post-marketing surveillance data from the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database for suture-based vascular closure devices (VCDs) - Perclose ProGlide (Abbott, Chicago, Illinois) and Prostar XL (Abbott).

BACKGROUND

Suture-based VCDs are mostly used for large-bore femoral arterial access-site closure. Real-world, contemporary experience on the most commonly reported complications and modes of failure associated with these devices is limited.

METHODS

Post-marketing surveillance data from the FDA MAUDE database, for the ProGlide system and for the Prostar XL system, were analyzed, yielding 827 Perclose ProGlide reports and 175 Prostar XL reports.

RESULTS

Of the 827 reports of major complications involving the Perclose ProGlide devices, 404 reports involved injury, and one involved death related to the device. In the Prostar XL analysis, 94 reports involved injury, and one involved death. Bleeding from vessel injury was the most common adverse outcome described with both devices, followed by hematoma and thrombus. Surgical repair was the most commonly used treatment strategy. In terms of device malfunction, suture-related malfunction (212 reports) was most commonly seen in the Perclose ProGlide group, while failed deployment was most commonly seen in the Prostar XL group.

CONCLUSIONS

Our analysis of the MAUDE database demonstrates that in real-world practice, suture-based VCDs were found to be associated with complications, including vascular injury, difficulties with the device itself, and even death. Ongoing user education and pre-procedural patient selection are important to minimize risks associated with suture-based vascular closure devices.

Real-World Experience of the MANTA Closure Device: Insights From the FDA Manufacturer and User Facility Device Experience (MAUDE) Database

BACKGROUND/PURPOSE

The MANTA vascular closure device (VCD) is the first commercially available dedicated closure device for large-bore femoral arterial access-site closure and was approved by the United States Food and Drug Administration (FDA) in February 2019. Real-world data on the most commonly reported complications and modes of failure associated with the MANTA closure device are limited. We analyzed post-marketing surveillance data from FDA's Manufacturer and User Facility Device Experience (MAUDE) database for the MANTA VCD (Teleflex, Wayne, Pennsylvania).

METHODS/MATERIALS

Post-marketing surveillance data from the FDA MAUDE database from February 2019 through March 2020 were analyzed, yielding 170 reports.

RESULTS

Of the 170 reports of major complications involving MANTA devices, 141 reports involved either injury (136) or death (5) related to the device. Of the 141 reports, bleeding was the most common adverse outcome described (45), followed by vessel occlusion (30) and vessel dissection (21). Device malfunction incidents (29 reports) were reported in 4 main categories: failed deployment (16 reports), malposition of the collagen (9), insufficient information (3), and device dislocation (1).

CONCLUSIONS

Our analysis of the MAUDE database demonstrates that in real-world practice, the MANTA VCD was found to be associated with complications, including death, vascular injury, and difficulties with the device itself. Ongoing user education, proctoring, and pre-procedural patient selection are important to minimize risks associated with the MANTA VCD.

Fatigue of textiles used in vascular surgery: Application to carotid endarterectomy

Fatigue is a material-based phenomenon playing a significant role in the mechanical behavior of components and structures. Although fatigue has been well studied for traditional materials, such as metals, its underlying mechanisms are not thoroughly understood in novel applications such as the case of textiles used as patches to close the arteriotomy in carotid endarterectomy. The latter is a type of vascular surgery for the treatment of carotid artery disease in which after an arteriotomy and removal of atherosclerotic plaque closure is made with a patch sutured on the artery. Completion of the operation signals the initiation of complex mechanical and hemodynamic phenomena. Fatigue performance of the patch eventually determines the successful outcome of carotid endarterectomy. In this study, we evaluate with a two-fold approach the mechanics of patch angioplasty in carotid endarterectomy. First, an analytical model for the fatigue behavior of textiles is developed, considering the microstructure and geometry of the fabric. Then, the surgical procedure is simulated and a finite element analysis of the endarterectomized and patched carotid artery is employed. Stress fields are calculated, while deformation at the site of patch angioplasty indicates a potential cause for the formation of aneurismal degeneration after the surgery. Such analysis can provide a better understanding in the establishment of follow-up protocols.

Radial Recurrent Artery: Autologous Patch Graft for Acute Brachial Artery Laceration

Brachial artery injury is the most common vascular disruption in upper extremity penetrating trauma, usually treated by primary repair or saphenous vein interposition graft. We report the case of a young male who presented after assault with stab wound to the right antecubital fossa, an asymmetric vascular exam, and unknown depth contaminated wound that warranted operative exploration. We performed open exploration through a triangular flap extension of his oblique linear laceration for both exposure and flexor surface scar contracture prophylaxis. Exploration revealed brachial artery laceration with loss of approximately 30% of vessel circumference proximal to the radial and ulnar artery bifurcation. A near-complete transection of the recurrent radial artery was also present, leading to the decision to sacrifice this vessel for use as an autologous patch graft of the injured brachial artery. Distal vascular flow was re-established, and the vessel was slightly ectatic with no evidence of stenosis. Patient suffered no complications and was discharged at post-operative day four after perioperative heparin drip on anti-platelet therapy. Autologous patch grafting in the acute setting is a less-often considered surgical option that is effective for arterial bifurcation reconstruction, which may be employed through the sacrifice of injured and redundant local branch vessels. Patch grafts are commonly utilized in planned vascular surgery, such as carotid endarterectomy, but this is the first report of autologous patch graft to an acute brachial artery injury. By combining knowledge of the lateral arm flap with the plastic surgery principles of "like replaces like", this technique avoids the stenosis associated with primary repair, the multiple anastomoses necessary for interposition grafting, the need for a secondary donor site, and provides a theoretical blood-flow advantage.

Biodegradable Patches for Arterial Reconstruction Modified with RGD Peptides: Results of an Experimental Study

Modification by Arg-Gly-Asp (RGD) peptides is a promising approach to improve the biocompatibility of biodegradable vascular patches for arteriotomy. In this study, we evaluated the performance of vascular patches electrospun using a blend of polycaprolactone (PCL) and polyhydroxybutyrate/valerate (PHBV) and additionally modified with RGDK, AhRGD, and c[RGDFK] peptides using 1,6-hexamethylenediamine or 4,7,10-trioxa-1,13-tridecanediamine (TTDDA) linkers. We examined mechanical properties and hemocompatibility of resulting patches before implanting them in rat abdominal aortas to assess their performance in vivo. Patches were explanted 1, 3, 6, and 12 months postoperation followed by histological and immunofluorescence analyses. Patches manufactured from the human internal mammary artery or commercially available KemPeriplas-Neo xenopericardial patches were used as a control. The tensile strength and F _max of KemPeriplas-Neo patches were 4- and 16.7-times higher than those made of human internal mammary artery, respectively. Both RGD-modified and unmodified PHBV/PCL patches demonstrated properties similar to a human internal mammary artery patch. Regardless of RGD modification, experimental PHBV/PCL patches displayed fewer lysed red blood cells and resulted in milder platelet aggregation than KemPeriplas-Neo patches. Xenopericardial patches failed to form an endothelial layer in vivo and were prone to calcification. By contrast, TTDDA/RGDK-modified biodegradable patches demonstrated a resistance to calcification. Modification by TTDDA/RGDK and TTDDA/c[RGDFK] facilitated the formation of neovasculature upon the implantation in vivo.

Long-term Durability and Safety of Carotid Endarterectomy Closure Techniques

BACKGROUND

Various techniques have been used for the execution of carotid endarterectomy; primary (PC), patch closure (CP) and eversion technique (ET).The superiority of any of them is still unproven. The aim of this study was to compare the long-term outcomes of each technique in terms of cerebrovascular event (CVE), restenosis, survival and major cardiac event (MACE).

METHODS

Between 2007 and 2018, a retrospective analysis of prospectively recorded data from three European tertiary centers was undertaken including 1.357 patients. Demographics, comorbidities and medical treatment were analyzed in relation to long-term outcomes. Freedom from CVE, restenosis (> 70%), survival and MACE were estimated with Kaplan-Meier analysis curve.

RESULTS

The mean age was 69.5 ± 8 (72% males;79% asymptomatic). 472 (35%) were treated with PC, 504 (37%) with CP and 381 (28%) with ET. Differences among groups were observed in age (P < 0.001), gender (P < 0.01), hypertension (P = 0.01), dyslipidemia (P < 0.001) and statin treatment (P < 0.001). The mean follow-up was 4.7 ± 3 years (median: 5 years). Seventy-three patients presented a CVE during 8 years of follow-up. The freedom from CVE including all techniques was 96% (SE 0.6%), 93% (SE 1%) and 89% (SE 1.6%), at 2, 5 and 8 years of follow-up, respectively, with no difference between groups (P .289). Freedom from restenosis was at 96% (SE 0.7%) and 89% (SE 5%) at 5 and 10 years, respectively, for all methods without differences. ET was associated with a higher mortality rate (P < 0.001) and MACE rate (P < 0.001).

CONCLUSIONS

Excellent outcomes were achieved with all types of closure techniques with low rates of MACE and other adverse events during long-term follow-up after CEA.

Hyaluronic acid-heparin conjugated decellularized human great saphenous vein patches decrease neointimal thickness

Although the science of implantable materials has advanced therapeutic options in vascular surgery, graft failure is still a problem in need of a durable solution. With the development of coating and decellularization techniques, coated prosthetic grafts have become an option; however, whether decellularized human saphenous vein can be conjugated and implanted is not known. Human great saphenous vein (GSV) was harvested and decellularized and hyaluronic acid (HA)-heparin was conjugated to the GSV; water contact angles (WCA), morphology, and sulfur element change were measured before and after heparin bonding. GSV patches were implanted into the rat inferior vena cava and aorta; patches were harvested (Day 14) and analyzed. HA-heparin was successfully conjugated to the decellularized human GSV with altered morphology and reduced WCA. The HA-heparin coated decellularized GSV patch was anti-thrombotic in vitro, and significantly decreased neointimal thickness both in patch venoplasty and angioplasty in a rat model. Both CD90 and nestin positive cells participated in neointima formation. These data show that HA-heparin coated human GSV patches decrease neointimal thickness when used both in venoplasty and arterioplasty. Tissue engineered decellularized human GSV is a promising vascular prosthesis.

Polysaccharide-based tissue-engineered vascular patches

Coronary artery and peripheral vascular diseases are the leading cause of morbidity and mortality worldwide and often require surgical intervention to replace damaged blood vessels, including the use of vascular patches in endarterectomy procedures. Tissue engineering approaches can be used to obtain biocompatible and biodegradable materials directed to this application. In this work, dense or porous scaffolds constituted of chitosan (Ch) complexed with alginate (A) or pectin (P) were fabricated and characterized considering their application as tissue-engineered vascular patches. Scaffolds fabricated with alginate presented higher culture medium uptake capacity (up to 17 g/g) than materials produced with pectin. A degradation study of the patches in the presence of lysozyme showed longer-term stability for Ch-P-based scaffolds. Pectin-containing matrices presented higher elastic modulus (around 280 kPa) and ability to withstand larger deformations. Moreover, these materials demonstrated better performance when tested for hemocompatibility, with lower levels of platelet adhesion and activation. Human smooth muscle cells (HSMC) adhered, spread and proliferated better on matrices produced with pectin, probably as a consequence of cell response to higher stiffness of this material. Thus, the outcomes of this study demonstrate that Ch-P-based scaffolds present superior characteristics for the application as vascular patches. Despite polysaccharides are yet underrated in this field, this work shows that biocompatible tridimensional structures based on these polymers present high potential to be applied for the reconstruction and regeneration of vascular tissues.

A novel human-derived tissue-engineered patch for vascular reconstruction

Vascular patches are commonly applied in tissue repair and reconstruction in congenital cardiac surgery. However, the currently available patch materials are inappropriate to be used in the pediatric population due to their lack of supporting tissue growth potential. In our study an active patch material was developed by seeding pediatric patient's bone marrow stem cells on a decellularized aortic extracellular matrix (ECM) scaffold. The patch was then implanted to repair abdominal aorta defects of nude rats. Two months after implantation, tissue remodeling, vascular cell regeneration, and cellular integration were investigated using histology and fluorescent staining. Histology demonstrated infiltration of host cells and formation of organized cell layers as well as intact collagen and elastic fibers inside the patch material. Immunofluorescence indicated regeneration of endothelial and smooth muscle cells. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) identified multiple vascularization-promoting components and growth factors in decellularized aortic ECM scaffold. These results demonstrated growth potential and suitability of human derived tissue-engineered patch for vascular reconstruction, and thus, it might be considered in the future as treatment option in pediatric patients.

Perioperative and Follow-up Results of Carotid Artery Stenting and Carotid Endarterectomy in Patients with Carotid Near-Occlusion

BACKGROUND

The aim was to compare perioperative and follow-up results of carotid artery stenting (CAS) and carotid endarterectomy (CEA) in patients with carotid near-occlusion (NO).

METHODS

A retrospective analysis was conducted from January 2012 to June 2017 on consecutive patients with NO in our center. Perioperative complications, recurrence rate of ischemic stroke, restenosis rate, and mortality in follow-up were compared between the CAS group and CEA group.

RESULTS

92 patients (CAS group, 54 and CEA group, 38) were identified. Perioperative (30-day) results were as follows: the rate of new lesions on diffusion-weighted imaging (DWI) was higher in the CAS group (n = 31, 57.4%) than in the CEA group (n = 13, 34.2%) (P = 0.03); no differences were found in ischemic stroke, transient ischemic attack (TIA), cardiac infarction, and death rate between the two groups. Results from follow-up with a mean period of 28.3 (range from 3 to 60) months were as follows: the restenosis rate was lower in the CAS group (n = 1, 1.8%) than the CEA group (n = 4, 10.5%) (P = 0.04); no differences were found in ischemic stroke, TIA, and the death rate between the two groups. Kaplan-Meier survival curves showed that the five-year survival rate was 85.8% of the CAS group and 82.7% of the CEA group (P = 0.61); the five-year rate of freedom from target-lesion restenosis was 93.3% of the CAS group and 80.4% of the CEA group (P = 0.02).

CONCLUSIONS

Both CAS and CEA can be used for carotid NO with the same rate of TIA/stroke and long-term survival. The rate of new lesions on DWI after CAS was higher than that in CEA in the perioperative period. CAS had a lower restenosis rate than CEA in follow-up, which might be more beneficial for remodeling of the distal internal carotid artery.

Replacement of infected aortoiliac vascular grafts with bifurcated BioIntegral Surgical No-React® bovine pericardial xenografts

The infection of a vascular prosthesis is potentially fatal, and its effective treatment still remains the greatest challenge for vascular surgeons. We present our initial experience using bovine pericardial vascular prostheses to replace infected aortoiliac vascular grafts. Six consecutive patients with infection of the graft were prospectively included in this study. Infection of the vascular graft was confirmed by clinical symptoms, laboratory tests and the results of computed tomography and positron emission tomography/computed tomography. In all cases, the infected aortoiliac graft was surgically removed and replaced by the bovine-pericardial BioIntegral aortic-bifemoral prosthesis. Technical success was achieved in every case with no in-hospital or 30 days mortality. One patient required revision of distal anastomosis due to recurrent bleeding at day four after surgery. One patient presented with upper gastrointestinal tract bleeding during the postoperative period, which was managed endoscopically. The mean hospital stay was 14 days (range 9-19). The control CT scan performed 2 months after surgery showed significant regression of abscesses and periprosthetic inflammation. Two patients died within 32 months of follow-up: one due to heart attack, the other due to generalized sepsis, which was correlated with the previous infection. Four patients are still in follow-up. The BioIntegral prosthesis is patent in all four cases, with no clinical or ultrasonographic signs of infection. Our brief investigation shows that a bovine pericardial prosthesis may be a valuable option in the treatment of vascular grafts infections.

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.

Carotid Artery Involvement in Advanced Recurrent Head and Neck Cancer: A Case Report and Literature Review

BACKGROUND

Surgical management of advanced head and neck tumors involving the carotid artery remains controversial with compromised survival outcomes and heightened risks of morbidity and mortality.

CASE

We describe a case of a 74-year-old lady with previous T1N0M0 left tongue squamous cell carcinoma, who developed a left nodal recurrence encasing the left external carotid artery from the carotid bifurcation. She underwent an extended left radical neck dissection with carotid artery patch plasty and remains well to date, 10 months after surgery.

DISCUSSION

Head and neck tumor recurrences are not uncommon, and radical resection of advanced tumors involving the carotid artery is increasingly performed. Various carotid interventions including tumor peeling, ligation, and resection with reconstruction were reported with differences in survival outcomes, morbidity and mortality.

CONCLUSION

An aggressive surgical approach to advanced tumors involving the carotid artery may be a viable attempt for survival prolongation but requires proper case selection and has to be weighed against the risks of complications to better optimize patient outcomes.

Biomechanical Aspects of Closing Approaches in Postcarotid Endarterectomy

The carotid bifurcation tends to develop atherosclerotic stenoses which might interfere with cerebral blood supply. In cases of arterial blockage, the common clinical solution is to remove the plaque via carotid endarterectomy (CEA) surgery. Artery closure after surgery using primary closures along the cutting edge might lead to artery narrowing and restrict blood flow. An alternative approach is patch angioplasty which takes longer time and leads to more during-surgery complications. The present study uses numerical methods with fluid-structure interaction (FSI) to explore and compare the two solutions in terms of hemodynamics and stress and strain fields developed in the artery wall.

Label-Free Assessment of Collagenase Digestion on Bovine Pericardium Properties by Fluorescence Lifetime Imaging

The extracellular matrix architecture of bovine pericardium (BP) has distinct biochemical and biomechanical properties that make it a useful biomaterial in the field of regenerative medicine. Collagen represents the dominant structural protein of BP and is therefore intimately associated with the properties of this biomaterial. Enzymatic degradation of collagen molecules is critical for extracellular matrix turnover, remodeling and ultimately tissue regeneration. We present a quantitative, label-free and non-destructive method for monitoring changes in biochemical and biomechanical properties of BP during tissue degradation, based on multi-spectral fluorescence lifetime imaging (ms-FLIm). Strong correlations of fluorescence intensity ratio and average fluorescence lifetime were identified with collagen content, Young's Modulus and Ultimate tensile strength during collagenase degradation, indicating the potential of optically monitoring collagen degradation using ms-FLIm. The obtained results demonstrate the value of ms-FLIm to assess the quality of biomaterials in situ for applications in regenerative medicine.

Right carotid-cutaneous fistula and right carotid pseudoaneurysm formation secondary to a chronically infected polyethylene terephthalate patch

Carotid endarterectomy (CEA) remains the treatment for significant carotid stenosis and stroke prevention. Approximately 100,000 CEAs are performed in the United States every year. Randomized trials have demonstrated an advantage of patch carotid angioplasty over primary closure. Complications from patches include thrombosis, transient ischemic attack, stroke, restenosis, pseudoaneurysm (PA), and infection. PA after CEA is rare, with a reported average of 0.37% of cases. We describe an unusual case of PA after polyethylene terephthalate (PTFE) patching for CEA. An 88-year-old female with Alzheimer's disease living in a nursing facility with a history of skin cancer on her right chest developed a new area of intermittent brisk bleeding on her right neck which was initially believed to be related to her skin cancer. She had a remote history of right CEA with a PTFE patch approximately a decade ago. A computed tomography angiograph-head-and-neck with showed a partially thrombosed PA in the region of her right common carotid artery bifurcation with a tract containing gas and fluid extending to the skin surface suspicious for a partially thrombosed, leaking PA. She was taken urgently to the operating room on broad-spectrum antibiotics where we performed a right neck exploration, ligation of a bleeding carotid PA by ligation of the right common, internal, and external carotid arteries, explantation of a chronically infected polyethylene terephthalate patch, and closure with a sternocleidomastoid advanced flap with multilayered closure. She was discharged to her nursing facility with 6 weeks of ceftriaxone intravenous (IV) and metronidazole IV through a peripherally inserted central catheter (PICC) line with no neurological sequelae.

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.

Infected symptomatic carotid artery atheroma concurrent with bacterial endocarditis

Optimal management of patients with stroke due to symptomatic carotid artery disease coexistent with bacterial endocarditis is still not well established. We report the case of a patient who presented with multifocal left middle cerebral artery stroke in the setting of Enterococcus faecalis endocarditis and was found to have near-occlusive ipsilateral carotid artery stenosis in stroke workup. Carotid artery endarterectomy was performed, and atheroma material demonstrated complicated plaque with cultures positive for E. faecalis This report demonstrates that patients with cardioembolic disorders such as bacterial endocarditis with vegetations who present with stroke may benefit from evaluation for extracranial vessel stenosis. Also, additional consideration should be given to the possibility of infected atheroma in patients with symptomatic carotid stenosis with recent or active endocarditis or bacteraemia.

Durability of Carotid Endarterectomy with Bovine Pericardial Patch

BACKGROUND

Multiple studies have shown that patch angioplasty after carotid endarterectomy (CEA) reduces the risk of stroke and restenosis when compared with primary closure. Biological, synthetic, or vein patches have been traditionally used in CEA. This article reports the early and long-term outcomes of bovine pericardium (BP) for patch angioplasty in CEA.

METHODS

A retrospective, consecutive analysis of 874 patients who underwent CEA during the past 17 years at Mayo Clinic, Florida, was performed. BP patch (BPP) was used in 680 patients. Other CEA techniques were used in 194 patients (standard without patch, 78; standard with Dacron, 74; standard with vein patch, 16; and other techniques: bypasses, 26). We defined group 1 as those who underwent BPP angioplasty and group 2 as those who underwent all other techniques. Early and late clinical outcomes and patch-related complications (restenosis, infection, and hematoma) were recorded and analyzed.

RESULTS

Median follow-up for the entire series was 39.6 months. There were no statistically significant differences in 30-day mortality and morbidity between the 2 groups, except that BP group has less 30-day stroke (0.1%, 1 of 680) versus other techniques (1.5%, 3 of 194, P = 0.03). Thirty-day postoperative mortality rate was 0.1% (1 of 680) in BPP group and 1.0% (2 of 194) in other technique group (P = 0.13). No statistically significant difference was noted in 30-day postoperative major complications (transient ischemic attack [TIA], wound infection, hematoma requiring surgical evacuation, and nerve injury) between the 2 groups. Ten-year freedom from stroke/TIA were 97.8% in the BP group compared with 98.5% in the other group (P = 0.86). Ten-year freedom from restenosis was also similar between groups (89.0% BP vs. 90.4% others, P = 0.69). Ten-year survival rate was 38.4% in BP group and 45.0% in other technique group, and this was statistically significant on univariate analysis only.

CONCLUSIONS

CEA with BP angioplasty has excellent early and late outcomes with minor morbidity and mortality.

Use of human aortic extracellular matrix as a scaffold for construction of a patient-specific tissue engineered vascular patch

Synthetic or biologic materials are usually used to repair vascular malformation in congenital heart defects; however, non-autologous materials show both mismatch compliance and antigenicity, as well as a lack of recellularization on its surface. Here, we constructed a tissue-engineered vascular patch (TEVP) using decellularized extracellular matrix (ECM) scaffold obtained from excised human aorta during surgery, which was seeded with patient-derived bone marrow CD34-positive (CD34+) progenitor cells. While cellular components were removed, the decellularized ECM scaffold retained native ECM composition, similar mechanical performance to undecellularized aortic tissue, and supported the adhesion, survival and proliferation of CD34+ progenitor cells. Interestingly, after in vitro seeding of decellularized aortic ECM scaffold for 21 d, CD34+ progenitor cells differentiated into mature vascular endothelial cells without addition of any growth factors, as confirmed by the increased levels of endothelial surface markers (CD31, Von Willebrand factor (VWF), VE-cadherin and ICAM-2) and upregulated gene levels (CD31, VWF and eNOS) concurrently with decreased expression of stem cell markers (CD133 and CD34), thus, resulting in surface endothelialization of decellularized ECM scaffold. Consequently, the patient-specific TEVP constructed in this study holds great potential for clinical use in pediatric patients with vascular malformation.

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.

Outcomes of Carotid Endarterectomy with Primary Closure

Carotid endarterectomy (CEA) reduces the risk of stroke in patients with internal carotid artery stenosis, although the optimal surgical technique is debated. The literature suggests that patch angioplasty reduces complication risk, although primary closure shortens cross-clamp time and eliminates complications associated with grafts. The objective of this study was to assess the complication rate after CEA with primary closure. Retrospective review of 240 consecutive patients between 2002 and 2010. Of these patients, 70% returned for follow-up visits for at least 2 or more years. Primary closure was used in all patients. The average cross-clamp time was 18 minutes. Complications in the immediate postoperative period within 30 days were as follows: stroke (n = 3; 1.1%), transient ischemic attack (TIA; n = 4; 1.5%), myocardial infarction (MI; n = 3; 1.1%), and death (n = 1; 0.4%). Short-term follow-up revealed eight patients who were found to have significant restenosis (>80%) by carotid duplex imaging. Two to ten year postoperative complication rates were as follows: stroke (n = 7; 4.2%), TIA (n = 7; 4.2%), amaurosis fugax (n = 1; 0.6%), MI (n = 8; 4.8%), and death (n = 28; 17%). Mortality was due to stroke or heart attack (n = 2; 1.2%), cancer (n = 7; 4.2%), and unknown causes (n = 19; 11%). This study presents our experience with complications after primary closure after CEA. In our experience, CEA is a safe and effective surgical means of preventing stroke in the short term. Well-designed prospective studies are needed to confirm specific patient characteristics in which primary closure and patch angioplasty are indicated.

Functional Modification of Electrospun Poly(ε-caprolactone) Vascular Grafts with the Fusion Protein VEGF-HGFI Enhanced Vascular Regeneration

Synthetic artificial vascular grafts have exhibited low patency rate and severe neointimal hyperplasia in replacing small-caliber arteries (<6 mm) because of their failure to generate a functional endothelium. In this study, small-caliber (2.0 mm) electrospun poly(ε-caprolactone) (PCL) vascular grafts were modified with a fusion protein VEGF-HGFI which consists of the class I hydrophobin (HGFI) and vascular endothelial growth factor (VEGF), via hydrophobic interactions. Immunofluorescence staining with the anti-VEGF antibody showed that VEGF-HGFI formed a protein layer on the surface of fibers in the grafts. Scanning electron microscopy (SEM) and mechanical measurements showed that VEGF-HGFI modification had no effect on the structure and mechanical properties of PCL grafts. Blood compatibility tests demonstrated a lower level of fibrinogen (FGN) absorption, platelet activation, and aggregation on the VEGF-HGFI-modified PCL mats than that on the bare PCL mats. The hemolysis rate was comparable in both the modified and bare PCL mats. In vitro culture of human umbilical vein endothelial cells (HUVECs) demonstrated that VEGF-HGFI modification could remarkably enhance nitric oxide (NO) production, prostacyclin₂ (PGI₂) release, and the uptake of acetylated low-density lipoprotein (Ac-LDL) by HUVECs. The healing characteristics of the modified grafts were examined in the replacement of rat abdominal aorta for up to 1 month. Immunofluorescence staining revealed that endothelialization, vascularization, and smooth muscle cell (SMC) regeneration were markedly improved in the VEGF-HGFI-modified PCL grafts. These results suggest that modification with fusion protein VEGF-HGFI is an effective method to improve the regeneration capacity of synthetic vascular grafts.