Atlas of Cell Repertoire Within Neointimal Lesions Is Metabolically Altered in Hypertensive Rats

BACKGROUND

High blood pressure has been suggested to accelerate vascular injury-induced neointimal formation and progression. However, little is known about the intricate relationships between vascular injury and hypertension in the context of arterial remodeling.

METHODS

Single-cell RNA-sequencing analysis was used to depict the cell atlas of carotid arteries of Wistar Kyoto rats and spontaneously hypertensive rats with or without balloon injury.

RESULTS

We found that hypertension significantly aggravated balloon injury-induced arterial stenosis. A total of 36 202 cells from carotid arteries with or without balloon injury were included in single-cell RNA-sequencing analysis. Cell composition analysis showed that vascular injury and hypertension independently induced distinct aortic cell phenotypic alterations including immune cells, endothelial cells (ECs), and smooth muscle cells. Specifically, our data showed that injury and hypertension-induced specific EC phenotypic alterations, and revealed a transition from functional ECs to hypermetabolic, and eventually dysfunctional ECs in hypertensive rats upon balloon injury. Importantly, our data also showed that vascular injury and hypertension-induced different smooth muscle cell phenotypic alterations, characterized by deferential expression of synthetic signatures. Interestingly, pathway analysis showed that dysregulated metabolic pathways were a common feature in monocytes/macrophages, ECs, and smooth muscle cells in response to injury and hypertension. Functionally, we demonstrate that inhibition of mitochondrial respiration significantly ameliorated injury-induced neointimal formation in spontaneously hypertensive rats.

CONCLUSIONS

This study provides the cell landscape changes of the main aortic cell phenotypic alterations in response to injury and hypertension. Our findings suggest that targeting cellular mitochondrial respiration could be a novel therapeutic for patients with hypertension undergoing vascular angioplasty.

Analysis of Extracranial Cerebrovascular Injuries: Clinical Predictors of Management and Outcomes

BACKGROUND

Optimal management of traumatic extracranial cerebrovascular injuries (ECVIs) remains undefined. We sought to evaluate the factors that influence management and neurologic outcomes (stroke and brain death) following traumatic ECVI.

METHODS

A retrospective review of a single level 1 trauma center's prospectively maintained data registry of patients older than 18 years of age with a diagnosis of ECVI was performed from 2013 to 2019. Injuries limited to the external carotid artery were excluded. Patient demographics, type of injury, timing of presentation, Biffl Classification of Cerebrovascular Injury Grade, Injury Severity Score (ISS), and Abbreviated Injury Scale were documented. Ultimate treatments (medical management and procedural interventions) and brain-related outcomes (stroke and brain death) were recorded.

RESULTS

ECVIs were identified in 96 patients. The primary mechanism of injury was blunt trauma (89.5% vs. 10.5%, blunt versus penetrating), with 70 cases (66%) of vertebral artery injury and 37 cases of carotid artery injury. Treatments included vascular intervention (6.5%) and medical management (93.5%). Overall outcomes included ipsilateral ischemic stroke (29%) and brain death (6.5%). In the carotid group, vascular intervention was associated with higher Biffl grades (mean Biffl 3.17 vs. 2.23; P = 0.087) and decreased incidence of brain death (0% vs. 19%, P = 0.006), with no difference seen in ISS scores. Brain death was associated with higher ISS scores (40.29 vs. 24.17, P = 0.01), lower glascow coma score on arrival (3.57 vs. 10.63, P < 0.001), and increased rates of ischemic stroke (71% vs. 30%, P = 0.025). In the vertebral group, neither Biffl grade nor ISS were associated with treatment or outcomes. Regarding the timing of stroke in ECVI, there was no significant difference in the time from presentation to cerebral infarction between the carotid and vertebral artery groups (24.7 hr vs. 21.20 hr, P = 0.739). After this window, 98% of the ECVI cases demonstrated no further aneurysmal degeneration or new neurological deficits beyond the early time period (mean follow-up 9.7 months).

CONCLUSIONS

Blunt cerebrovascular injuries should be viewed distinctly in the carotid and vertebral territories. In cases of injury to the carotid artery, Biffl grade and ISS score are associated with surgical intervention and neurologic events, respectively; vertebral artery injuries did not share this association. Neurologic deficits were detected in a similar time frame between the carotid artery and the vertebral artery injury groups and both groups had rare late neurologic events.

A chitosan hydrogel sealant with self-contractile characteristic: From rapid and long-term hemorrhage control to wound closure and repair

Emergent and long-term hemorrhage control is requisite and beneficial for reducing global mortality and postoperative complications (e.g., second bleeding and adverse tissue adhesion). Despite recent advance in injectable hydrogels for hemostasis, achieving rapid gelation, strong tissue-adhesive property and stable mechanical strength under fluid physiological environment is still challenging. Herein, we developed a novel chitosan hydrogel (CCS@gel) via dynamic Schiff base reaction and mussel-inspired catechol chemistry. The hydrogel possessed high gelation rate (<10 s), strong wet adhesiveness, excellent self-healing performance and biocompatibility. More importantly, the CCS@gel exhibited saline-induced contractile performance and mechanical enhancement, promoting its mechanical property in moist internal conditions. In vivo studies demonstrated its superior hemostatic efficacy for diverse anticoagulated visceral and carotid bleeding scenarios, compared to commercialized fibrin glue. The hydrogel-treated rats survived for 8 weeks with minimal inflammation and postoperative adhesion. These results revealed that the promising CCS@gel would be a facile, efficient and safe sealant for clinical hemorrhage control.

External carotid artery pseudoaneurysm following upper respiratory infection masquerading as a pharyngeal abscess in an 8-month-old

Pseudoaneurysms are very rare with an incidence of less than 0.1% in the pediatric population. Approximately 30 cases of carotid artery aneurysms in children have been published in the literature, usually affecting children over one year of age. We present one of the youngest cases in the literature; the patient is an 8-month old female with a strep throat infection complicated by pseudoaneurysm development of the external carotid artery. Because of the rarity of these lesions, there is little known regarding the types of clinical presentation and management. They are commonly the result of direct arterial trauma; however, they can also occur secondary to infection, connective tissue disease or arteritis. We are presenting a case with a highly atypical presentation. When present, pseudoaneurysms harbor the potential risk of life-threatening hemorrhage and warrant immediate management. It is important to be aware of cases and the treatment modalities used to guide future diagnosis and planning.

Plerixafor stimulates adhesive activity and endothelial regeneration of endothelial progenitor cells via elevating CXCR7 expression

AIMS

To assess the effects of plerixafor on function and endothelial regeneration of endothelial progenitor cells (EPCs).

METHODS

The proliferation and adhesion capacity of EPCs were evaluated in vitro. Furthermore, the expression levels of CXC chemokine receptor-7 (CXCR7) were detected before and after treatment with plerixafor. The CXCR7 expression of EPCs was knocked-down by RNA interference to evaluate the role of CXCR7 in regulating function of EPCs. A rat carotid artery injury model was established to assess the influences of plerixafor on endothelial regeneration.

RESULTS

Plerixafor stimulated adhesion capacity of EPCs, associating with upregulation of CXCR7 and activation of LFA-1 and VLA-4 molecules. Knockdown of CXCR7 slightly impaired proliferation capacity but significantly attenuated adhesion capacity of EPCs. Plerixafor facilitated endothelial repair at 7 days, while reduced neointimal hyperplasia at 7 and 14 days via recruiting more EPCs participating in endothelial reparation.

CONCLUSIONS

Plerixafor can positively regulate adhesion capacity of EPCs to HUVECs via elevating the expression level of CXCR7 and stimulating LFA-1 and VLA-4 molecules activation. Treatment with plerixafor accelerated re-endothelialization and inhibited neointimal hyperplasia after endoth elial injury, indicating that it can to be used for endothelial regeneration.

Inhibition of Neointima Hyperplasia, Inflammation, and Reactive Oxygen Species in Balloon-Injured Arteries by HVJ Envelope Vector-Mediated Delivery of Superoxide Dismutase Gene

Extracellular superoxide dismutase (EC-SOD) has been implicated in regulation of vascular function but its underlying molecular mechanism is largely unknown. These two-step experiments investigate whether hemagglutinating virus of Japan envelope (HVJ-E) vector-mediated EC-SOD gene delivery might protect against neointima formation, vascular inflammation, and reactive oxygen species (ROS) generation, and also explore cell growth signaling pathways. The first in-vitro experiment was performed to assess the transfection efficacy and safety of HVJ-E compared to lipofectamine®. Results revealed that HVJ-E has higher transfection efficiency and lower cytotoxicity than those of lipofectamine®. Another in-vivo study initially used balloon denudation to rat carotid artery, then delivered EC-SOD cDNA through the vector of HVJ-E. Arterial section with H&E staining from the animals 14 days after balloon injury showed a significant reduction of intima-to-media area ratio in EC-SOD transfected arteries when compared with control (empty vector-transfected arteries) (p < 0.05). Arterial tissue with EC-SOD gene delivery also exhibited lower levels of ROS, as assessed by fluorescent microphotography with dihydroethidium staining. Quantitative RT-PCR revealed that EC-SOD gene delivery significantly diminished mRNA expression of tumor necrosis factor (TNF)-α and interleukin (IL)-1β (p < 0.05 in all comparisons). An immunoblotting assay from vascular smooth muscle cell (VSMC) cultures showed that the EC-SOD transfected group attenuated the activation of MEK1/2, ERK1/2, and Akt signaling significantly. In conclusion, EC-SOD overexpression by HVJ-E vector inhibits neointima hyperplasia, inflammation, and ROS level triggered by balloon injury. The modulation of cell growth-signaling pathways by EC-SOD in VSMCs might play an important role in these inhibitory effects.

A paradigm of endothelium-protective and stent-free anti-restenotic therapy using biomimetic nanoclusters

Drug-eluting stents are the most commonly employed method to control post-angioplasty restenosis. Unfortunately, they exacerbate life-threatening stent thrombosis because of endothelium damage caused by both drug and stenting. To solve this major medical problem, an endothelium-protective and stent-free anti-restenotic method is highly desirable. Here we have generated a biomimetic intravenous delivery system using dendritic polymer-based nanoclusters, which were coated with platelet membranes for targeting to the injured arterial wall where restenosis occurs. These nanoclusters were loaded with an endothelium-protective epigenetic inhibitor (JQ1) or an endothelium-toxic status quo drug (rapamycin), and compared for their ability to mitigate restenosis without hindering the process of re-endothelialization. Fluorescence imaging of Cy5-tagged biomimetic nanoclusters indicated their robust homing to injured, but not uninjured arteries. Two weeks after angioplasty, compared to no-drug control, both rapamycin- and JQ1-loaded biomimetic nanoclusters substantially reduced (by >60%) neointimal hyperplasia, the primary cause of restenosis. However, whereas the rapamycin formulation impaired the endothelial re-coverage of the denuded inner arterial wall, the JQ1 formulation preserved endothelial recovery. In summary, we have created an endothelium-protective anti-restenotic system with biomimetic nanoclusters containing an epigenetic inhibitor. This system warrants further development for a non-thrombogenic and stent-free method for clinical applications.

Surpass Streamline Flow-Diverter Embolization Device for Treatment of Iatrogenic and Traumatic Internal Carotid Artery Injuries

Iatrogenic and traumatic cerebral internal carotid artery injuries are uncommon but potentially lethal complications. Direct surgical repair of ICA injuries may be difficult in an acute setting. However, endovascular treatment with a flow-diverter embolization device is a feasible alternative technique that we experienced. In this clinical report, we describe demographic data, radiographic images, lesion characteristics, endovascular procedure notes, postprocedural hospital course, and follow-up digital subtraction angiography of 5 patients. At least 6-month follow-up was available in all patients without occurrence of rebleeding and other complications.

Blunt Traumatic Extracranial Cerebrovascular Injury and Ischemic Stroke

Background

Ischemic stroke occurs in a significant subset of patients with blunt traumatic cerebrovascular injury (TCVI). The patients are victims of motor vehicle crashes, assaults or other high-energy collisions, and suffer ischemic stroke due to injury to the extracranial carotid or vertebral arteries.

Summary

An increasing number of patients with TCVI are being identified, largely because of the expanding use of computed tomography angiography for screening patients with blunt trauma. Patients with TCVI are particularly challenging to manage because they often suffer polytrauma, that is, numerous additional injuries including orthopedic, chest, abdominal, and head injuries. Presently, there is no consensus about optimal management.

Key Messages

Most literature about TCVI and stroke has been published in trauma, general surgery, and neurosurgery journals; because of this, and because these patients are managed primarily by trauma surgeons, patients with stroke due to TCVI have been essentially hidden from view of neurologists. This review is intended to bring this clinical entity to the attention of clinicians and investigators with specific expertise in neurology and stroke.

Delayed Carotid Pseudoaneurysms from Iatrogenic Clival Meningeal Branches Avulsion: Recognition and Proposed Management

BACKGROUND

Carotid injury during anterior skull base approaches is promptly recognizable and mandates immediate treatment; likewise, development of pseudoaneurysms after such injuries is anticipated and managed.

METHODS

We report here on the delayed development of a pseudoaneurysm as the result of avulsion of clival meningeal arteries that manifests as unalarming intraoperative bleeding.

RESULTS AND CONCLUSIONS

The bleeding is brisk and arterial but easily controlled. Immediate postoperative angiography is negative, necessitating repeated angiography to depict the delayed formation. It is best treated by endovascular means that maintains patency of the carotid artery, calling for the development of a suitable device that obliterates the opening of the pseudoaneurysm while maintaining carotid flow that is deployable in the tortuous carotid artery.

Eagle Syndrome Presenting after Blunt Trauma

As classically described, Eagle syndrome is an entity where patients develop pain or neurologic manifestations arising from an elongated styloid process and/or an ossified stylohyoid ligament irritating or compressing adjacent cranial nerves or the carotid arteries. Over the past few years, there have been reports of actual injury to the internal carotid artery with dissection, occlusion, and strokes. We present 3 cases identified after blunt trauma: 1 due to carotid compression and 2 due to actual injury to the internal carotid artery. Eagle syndrome should be a consideration in any patient with a carotid injury due to blunt trauma or suffering a syncopal episode which led to blunt trauma. Carotid stenting is an effective treatment modality for injury to the carotid artery when anticoagulation is contraindicated. Styloidectomy is performed for symptoms due to carotid artery compression or if there is concern for future carotid injury from the styloid process.

Current Trends in the Management of Iatrogenic Cervical Carotid Artery Injuries

This study was undertaken to elicit the opinion of experts regarding the management of iatrogenic injury to the carotid artery. A text questionnaire was transmitted by electronic mail to members of the Western Vascular Society concerning management of iatrogenic injury to the cervical carotid artery. Participants were asked to submit information regarding practice status and their preferred choices for the management of different clinical scenarios. The scenarios were: (1) large bore sheath (> 8.5F) cannulation of the carotid artery in anesthetized patients, (2) large bore sheath cannulation of the carotid artery in an awake patient, (3) delayed recognition of a misplaced sheath by > 4 hours, and (4) arterial puncture was recognized after only the entry needle (16-gauge) was introduced but before sheath insertion. Finally, the members were asked to comment on the management of abnormal findings on duplex scanning, such as intimal flap or pseudoaneurysm. A response rate of 42% was obtained (45/106 active members). Eighty-two percent of respondents had been in practice for longer than 10 years. Eighty-nine percent had seen this complication and 29% had cared for patients in whom subsequent neurologic deficit developed. The institutional incidence of such injury was 1-5 cases per year for 82% of respondents. Sixteen-gauge needle injury was managed by immediate removal and applied pressure by 98% of respondents. When large-bore sheath injury is recognized within 1 hour of insertion, 62% of respondents would remove the sheath and hold pressure, with or without obtaining a duplex ultrasound examination. However, if injury recognition was delayed for > 4 hours, 82% would proceed to surgery. Only 26% operated on asymptomatic carotid flap found on ultrasound, while the remaining 74% would base their decision on size and flow characteristics on ultrasound. The management of pseudoaneurysm differed significantly. Whereas 31% of respondents would manage this finding expectantly, 69% would proceed to surgery regardless of size or symptoms. Despite awareness of iatrogenic injury to the cervical carotid artery, the institutional incidence remains high. Two thirds of respondents would manage a misplaced sheath in the carotid artery nonoperatively if the injury was recognized immediately. However, if injury recognition was delayed for > 4 hours, the majority of respondents would remove the sheath surgically. While the management of intimal flap largely depended on size and flow characteristics, 69% of respondents would operate on a pseudoaneurysm regardless of size or symptoms. The results of this survey may serve as a guideline for the management of this potentially devastating injury.

Stent-Graft Treatment of Pseudoaneurysms and Arteriovenous Fistulae in the Carotid Artery

The purpose of this study was to assess the safety and efficacy of stent-graft placement in the management of arteriovenous fistulae (AVF) and pseudoaneurysms (PAs) involving the carotid artery (CA).

Twenty-two patients (16 men, 6 women) with a CA AVF ( n = 5) or PA ( n = 17) owing to a gunshot or stab wound, carotid endarterectomy, blunt trauma, a tumor, spontaneous dissection, or a central venous catheter were treated with percutaneous placement of stent grafts. The patients presented with tumor, bruit, headache, mouth and tracheostomy bleeding, transitory hemiparesis, seizure, or stroke. Diagnoses were made by using computed tomographic angiography (CTA) and digital subtraction angiography. Fourteen lesions were in the common CA; eight were in the internal CA. Homemade devices and stent grafts from a variety of manufacturers were employed. Follow-up evaluations included clinical, CTA, and Doppler ultrasound assessments.

All patients had resolution of the PA or AVF. In one patient with a large petrous PA, acute occlusion of the CA developed after placement of three balloon-expandable stent grafts, but there were no neurologic complications because the circle of Willis was functional. During follow-up ranging from 2 months to 13 years, asymptomatic 90% stenosis owing to stent compression was observed on Doppler ultrasound and angiographic examinations in a patient with an autologous vein–covered stent graft in the internal CA. Three other patients died of causes unrelated to stent-graft placement. In all other patients, the stent graft remained patent.

Our results indicate that stent grafting is an acceptable alternative to surgery in the treatment of AVF and PAs in the CA.

Life-threatening hemorrhage after zygomatic bone surgery. About 2 posttraumatic cases

INTRODUCTION

Management of zygomatic bone fractures is still debated. Method and delay for intervention has to be chosen considering respective issues of operative or conservative treatments, especially hemorrhagic complications. The maxillofacial surgeon must be able to determine life-threatening situations and to react appropriately.

CASES REPORT

We report 2 cases of external carotid branches pseudoaneurysm leading to massive hemorrhage after early or delayed zygomatic fracture surgery. The first patient underwent open reduction of fracture by intraoral approach. An active bleeding occurred in the immediate postoperative time. In the second case, a zygomatic osteotomy was performed 1 year after fracture. Bleeding occurred 2 weeks after surgery. In both cases, angiography demonstrated a pseudoaneurysm developed from the external carotid branches. Embolisation led to rapid bleeding control.

DISCUSSION

Severe hemorrhage resulting from maxillofacial trauma may be life-threatening. Once the "damage control" principles applied, selective embolisation of external carotid branches is an efficient alternative to surgery for the control of bleeding resulting from ruptured pseudoaneurysm.

Targeted delivery of human iPS-ECs overexpressing IL-8 receptors inhibits neointimal and inflammatory responses to vascular injury in the rat

Interleukin-8 (IL8) is highly expressed by injured arteries in a variety of diseases and is a chemoattractant for neutrophils which express IL8 receptors IL8RA and RB (IL8RA/B) on their membranes. Neutrophils interact with the damaged endothelium and initiate an inflammatory cascade at the site of injury. We have generated a novel translational targeted cell therapy for acute vascular injury using adenoviral vectors to overexpress IL8RA/B and green fluorescent protein (GFP) on the surface of endothelial cells (ECs) derived from human induced pluripotent stem cells (HiPS-IL8RA/B-ECs). We hypothesize that HiPS-IL8RA/B-ECs transfused intravenously into rats with balloon injury of the carotid artery will target to the injured site and compete with neutrophils, thus inhibiting inflammation and neointima formation. Young adult male Sprague-Dawley rats underwent balloon injury of the right carotid artery and received intravenous transfusion of saline vehicle, 1.5 × 10(6) HiPS-ECs, 1.5 × 10(6) HiPS-Null-ECs, or 1.5 × 10(6) HiPS-IL8RA/B-ECs immediately after endoluminal injury. Tissue distribution of HiPS-IL8RA/B-ECs was analyzed by a novel GFP DNA qPCR method. Cytokine and chemokine expression and leukocyte infiltration were measured in injured and uninjured arteries at 24 h postinjury by ELISA and immunohistochemistry, respectively. Neointimal, medial areas, and reendothelialization were measured 14 days postinjury. HiPS-IL8RA/B-ECs homed to injured arteries, inhibited inflammatory mediator expression and inflammatory cell infiltration, accelerated reendothelialization, and attenuated neointima formation after endoluminal injury while control HiPS-ECs and HiPS-Null-ECs did not. HiPS-IL8RA/B-ECs transfused into rats with endoluminal carotid artery injury target to the injured artery and provide a novel strategy to treat vascular injury.

Basilar skull fractures: the petrous bone

Basilar skullfractures: the petrous bone.

OBJECTIVES

to provide suggestions for the management of three of the most dangerous or important lesions (internal carotid artery lesions, cerebrospinal fluid leaks and facial nerve paralysis) associated with the petrous part of basilar skull fractures, thereby trying to assess categories of evidence and determine strengths of recommendation.

METHODOLOGY

A PubMed-based literature review was carried out, as well as a consultation of online sources as encountered in the literature review. Also, a non-systematic search of chapters of well-known books dealing with the subject of temporal bone traumata was conducted.

RESULTS

Specific levels of evidence and/or strength of recommendation can be retrieved from the literature, but only with respect to the prophylactic use of antibiotics, the prescription of antithrombotic medications and the indications for angiography.

CONCLUSION

The ample amount of available literature allows for sound management decisions, with reference made to algorithms when available in the literature. Nevertheless, for most of the management/search questions, categories of evidence and strength of recommendation are low or lacking.

Soluble epoxide hydrolase is involved in the development of atherosclerosis and arterial neointima formation by regulating smooth muscle cell migration

Epoxyeicosatrienoic acids (EETs) have beneficial effects on cardiovascular disease. Soluble epoxide hydrolase (sEH) metabolizes EETs to less active diols, thus diminishing their biological activity. sEH inhibitors can suppress the progression of atherosclerotic lesions in animal models. However, the regulation of sEH in vascular smooth muscle cells (VSMCs) and role of sEH in patients with atherosclerosis have not been evaluated. We hypothesize that sEH in VSMCs plays a pivotal role in atherosclerosis and injury-induced neointima formation. In this study, sEH expression in human autopsy atherosclerotic plaque was determined by immunohistochemistry. In cultured rat and human VSMCs, the phenotypic switching marker and sEH expression induced by platelet-derived growth factor-BB (PDGF-BB) were examined by Western blot analysis. Carotid-artery balloon injury was performed after adenovirus-mediated overexpression of sEH or oral administration of a potent sEH inhibitor in Sprague-Dawley rats. sEH was highly expressed in VSMCs of the intima and media within human atherosclerotic plaque. In vitro, PDGF-BB upregulated the expression in VSMCs after transcription and promoted cell proliferation and migration; the latter effect could be largely attenuated by an sEH inhibitor. Adenovirus-mediated overexpression of sEH could mimic the effect of PDGF-BB and induce VSMC proliferation and migration. In vivo, the sEH inhibitor led to a significant decrease in injury-induced neointima formation in a rat carotid-artery injury model. These data establish the effect of sEH expression on atherosclerotic progression and vascular remodeling after injury, thus identifying a novel integrative role for sEH in VSMC phenotypic modulation and migration. Blocking sEH activity may be a potential therapeutic approach for ameliorating vascular occlusive disease.

Mesenchymal Stem Cells Stabilize Atherosclerotic Vulnerable Plaque by Anti-Inflammatory Properties

Background and objectives

Formation and progression of atherosclerotic vulnerable plaque (VP) is the primary cause of many cardio-cerebrovascular diseases such as acute coronary syndrome and stroke. It has been reported that bone marrow mesenchymal stem cells (MSC) exhibit protective effects against many kinds of diseases including myocardial infarction. Here, we examined the effects of intravenous MSC infusion on a VP model and provide novel evidence of its influence as a therapy in this animal disease model.

Subjects and methods

Thirty healthy male New Zealand white rabbits were randomly divided into a MSC, VP or stable plaque (SP) group (n = 10/group) and received high fat diet and cold-induced common carotid artery intimal injury with liquid nitrogen to form atherosclerotic plaques. Serum hs-CRP, TNF-α, IL-6 and IL-10 levels were measured by ELISA at 1, 2, 3, 7, 14, 21 and 28 days after MSC transplantation. The animals were sacrificed at 4 weeks after MSC transplantation. Lesions in the right common carotid were observed using H&E and Masson staining, and the fibrous cap/lipid core ratio of atherosclerotic plaques were calculated. The expression of nuclear factor κB (NF-κB) and matrix metalloproteinase 1, 2, 9 (MMP-1,2,9) in the plaque were detected using immunohistochemistry, and apoptotic cells in the plaques were detected by TUNEL. In addition, the level of TNF-α stimulated gene/protein 6 (TSG-6) mRNA and protein were measured by quantitative Real-Time PCR and Western blotting, respectively.

Results

Two rabbits in the VP group died of lung infection and cerebral infarction respectively at 1 week after plaque injury by liquid nitrogen. Both H&E and Masson staining revealed that the plaques from the SP and MSC groups had more stable morphological structure and a larger fibrous cap/lipid core ratio than the VP group. Serum hs-CRP, TNF-α and IL-6 were significantly down-regulated, whereas IL-10 was significantly up-regulated in the MSC group compared with the VP group. .Immunohistochemistry analysis revealed that NF-κB and MMP expression was reduced in the MSC and SP groups compared to the VP group. Cell apoptosis decreased significantly in both the MSC and SP groups in comparison to the VP group. TSG-6 mRNA and protein expression were higher in the plaques of the MSC group compared to the VP and SP groups.

Conclusions

Our study results suggest that MSC transplantation can effectively stabilize vulnerable plaques in atherosclerotic rabbits. This may potentially offer a new clinical application of MSC in atherosclerosis.

Meta-analysis of the effect of mesenchymal stem cell transplantation on vascular remodeling after carotid balloon injury in animal models

AIM

A meta-analysis was conducted to assess the efficacy of mesenchymal stem cell (MSC) transplantation in small animal coronary vessels after balloon injury, to provide data for the design of future pre-clinical experiments and human clinical trials.

METHODS

The search strategy included the PubMed, EMBASE, Chinese Biomedical Literature (CBM), and China National Knowledge Infrastructure (CKNI) databases. The endpoint was the ratio of vascular neointima/media (I/M). Moreover, neointimal area, re-endothelialization, and proliferating cell nuclear antigen (PCNA) expression were analyzed. Pooled analyses were conducted using random effects models. Heterogeneity and publication bias were also explored. All data were analyzed using RevMan 5.2 and Stata 12.0.

RESULTS

Fifteen studies were reviewed from 238 retrieved animal studies. Compared with controls, MSC transplantation resulted in greater I/M reduction (pooled difference, 0.39; 95% CI, 0.57-0.21; P < 0.0001), greater neointimal area reduction (pooled difference, 0.16; 95% CI, 0.22-0.10; P < 0.0001), decreased PCNA expression (pooled difference, 17.69; 95% CI, 28.94-6.44; P = 0.002), and enhanced re-endothelialization (pooled difference, 3.37; 95% CI, 1.78-4.95; P < 0.0001). The multivariable meta-regression analysis showed that a higher number of transplanted cells (>106; P = 0.017) and later time point of I/M measurement (P = 0.022) were significantly associated with I/M reduction. Subgroup analysis demonstrated a trend for a greater reduction in the ratio of I/M with late MSC transplantation (>1 day), MSCs transplanted through intravenous injection, and atherosclerotic vessels.

CONCLUSION

The meta-analysis results demonstrate that MSC transplantation might improve injured vascular remodeling. In addition to greater efficacy with a greater number of transplanted MSCs (>106), the long-term effect of MSC transplantation appears to be more significant. The findings of this meta-analysis may help to design future, effective MSC trials.

Direct traumatic carotid cavernous fistula: angiographic classification and treatment strategies. Study of 172 cases

We report our experience in treatment of traumatic direct carotid cavernous fistula (CCF) via endovascular intervention. We hereof recommend an additional classification system for type A CCF and suggest respective treatment strategies. Only type A CCF patients (Barrow's classification) would be recruited for the study. Based on the angiographic characteristics of the CCF, we classified type A CCF into three subtypes including small size, medium size and large size fistula depending on whether there was presence of the anterior carotid artery (ACA) and/or middle carotid artery (MCA). Angiograms with opacification of both ACA and MCA were categorized as small size fistula. Angiograms with opacification of either ACA or MCA were categorized as medium size fistula and those without opacification of neither ACA nor MCA were classified as large size fiatula. After the confirm angiogram, endovascular embolization would be performed impromptu using detachable balloon, coils or both. All cases were followed up for complication and effect after the embolization. A total of 172 direct traumatic CCF patients were enrolled. The small size fistula was accountant for 12.8% (22 cases), medium size 35.5% (61 cases) and large size fistula accountant for 51.7% (89 cases). The successful rate of fistula occlusion under endovascular embolization was 94% with preservation of the carotid artery in 70%. For the treatment of each subtype, a total of 21/22 cases of the small size fistulas were successfully treated using coils alone. The other single case of small fistula was defaulted. Most of the medium and large size fistulas were cured using detachable balloons. When the fistula sealing could not be obtained using detachable balloon, coils were added to affirm the embolization of the cavernous sinus via venous access. There were about 2.9% of patient experienced direct carotid artery puncture and 0.6% puncture after carotid artery cut-down exposure. About 30% of cases experienced sacrifice of the parent vessels and it was associated with sizes of the fistula. Total severe complication was about 2.4% which included 1 death (0.6%) due to vagal shock; 1 transient hemiparesis post-sacrifice occlusion of the carotid artery but the patient had recovered after 3 months; 1 acute thrombus embolism and the patient was completely saved with recombinant tissue plaminogen activator (rTPA); 1 balloon dislodgement then got stuck at the anterior communicating artery but the patient was asymptomatic. Endovascular intervention as the treatment of direct traumatic CCF had high cure rate and low complication with its ability to preserve the carotid artery. It also can supply flexible accesses to the fistulous site with various alternative embolic materials. The new classification of type A CCF based on angiographic features was helpful for planning for the embolization. Coil should be considered as the first embolic material for small size fistula meanwhile detachable balloons was suggested as the first-choice embolic agent for the medium and large size fistula.

Flank sequences of miR-145/143 and their aberrant expression in vascular disease: mechanism and therapeutic application

BACKGROUND

Many microRNAs (miRNAs) are downregulated in proliferative vascular disease. Thus, upregulation of these miRNAs has become a major focus of research activity. However, there is a critical barrier in gene therapy to upregulate some miRNAs such as miR-145 and miR-143 because of their significant downregulation by the unclear endogenous mechanisms under disease conditions. The purpose of this study was to determine the molecular mechanisms responsible for their downregulation and to overcome the therapeutic barrier.

METHODS AND RESULTS

In cultured proliferative rat vascular smooth muscle cells (VSMCs) in vitro and in diseased rat and mouse arteries in vivo, we have identified that the impairment of pri-miR-145 into pre-miR-145 is the critical step related to the downregulation of miR-145, in which the PI3-kinase/Akt/p53 pathway is involved. We further identified that the flank sequences of pri-miR-145 are the critical structural components responsible for the aberrant miR-145 expression. Switching of the flank sequence of downregulated miR-145 and miR-143 to the flank sequence of miR-31 confers resistance to their downregulation. The genetically engineered miR-145 (smart miR-145) restored the downregulated miR-145 in proliferative rat VSMCs and in rat carotid arteries with balloon injury and mouse atherosclerotic aortas and demonstrated much better therapeutic effects on the abnormal growth of VSMCs, expression of its target gene, KLF5 expression, VSMC marker gene expression, and vascular neointimal growth.

CONCLUSIONS

The flank sequences of miR-145 and miR-143 play a critical role in their aberrant expression in VSMCs and vascular walls. The genetically engineered "smart" miRNAs based on their flank sequences may have broadly therapeutic applications for many vascular diseases.

[Effects of batroxobin and electric cauterization on vascular remodeling of rabbit with a removal of carotid arterial adventitia]

OBJECTIVE

To explore the topical hemostatic effects of batroxobin (BX) and electric cauterization (EC) on capillary hemorrhage of rabbit with a removal of carotid arterial adventitia.

METHODS

A total of 27 New Zealand rabbits were randomly divided into control, BX and EC groups. Each group received BX (2 kU/L), EC (power = 40 W) and saline for topical hemostasis after a removal of carotid arterial adventitia and blunt dissection. The animals were euthanized by 0, 14 and 28 d post-operation. The specimens of adventitia removal section were divided into three parts for histology (hematoxylin and eosin, MASSON & transmission electron microscope), immunohistochemistry (IHC) [monocyte chemoattractant protein-1 (MCP-1), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF)] and reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

At Day 28 post-operation, the remodeling index, stenotic rate and collagen fiber density of BX and EC groups were (0.753 ± 0.0739) and (0.618 ± 0.0989), (0.298 ± 0.030)% and (0.363 ± 0.039)%, (15.4 ± 3.5)% and (23.4 ± 5.1)% respectively. There was statistically significant difference between two groups (P < 0.05) while no difference existed between hemocoagulase and control groups. The results of electron microscopy showed that the atrial fibroblasts of EC group increased markedly versus BX group. As demonstrated by RT-PCR and IHC, the expressions of MCP-1, TGF-β1 and VEGF in BX group were lower than those in EC group (P < 0.05) while no difference versus the control group.

CONCLUSION

As a safe and effective topical hemostatic method, BX can effectively decrease inflammation response and reduce vascular remodeling and narrowing in rabbits with a removal of carotid arterial adventitia. And its effect mimic closely natural conditions.

Transplantation of human umbilical cord-derived endothelial progenitor cells promotes re-endothelialization of the injured carotid artery after balloon injury in New Zealand white rabbits

BACKGROUND

Cell transplantation has great potential for promoting endothelial repair and reducing the complications of percutaneous coronary intervention (PCI). The aim of this study was to investigate the effect of transplantation of human umbilical cord blood endothelial progenitor cells (EPCs) on injured arteries.

METHODS

Umbilical cord blood mononuclear cells were obtained from post-partum lying-in women, and EPCs were isolated, cultured, expanded and identified by immunofluorescence. The carotid arterial endothelium of New Zealand white rabbits was injured by dilatation with a 3F balloon, and the EPCs were injected into the lumen of the injured artery in the transplanted group (n = 16), while an equal volume of phosphated buffered saline (PBS) was injected into the control group after balloon injury (n = 16). The animals were sacrificed after either 2 or 4 weeks, and the grafted cells were identified by double immunofluorescence staining with human nuclear antigen (HNA) and CD31 antibodies. Arterial cross sections were analyzed by pathology, immunohistochemistry and morphometry to evaluate the reparative effects of EPCs. Proliferating cell nuclear antigen (PCNA) and transforming growth factor (TGF)-β1 mRNA expression were detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Fluorescence-labeled EPCs were found in the neointima. The neointimal area and the neointimal/medial area ratio were significantly lower in the transplanted group than in the control group (P < 0.05). von Willebrand factor (vWF) immunohistostaining showed more VWF-positive cells in the transplanted animals than in the controls (8.75 ± 2.92 vs. 4.50 ± 1.77, P < 0.05). Compared with the control group, the transplanted group had lower expression of PCNA mRNA (0.67 ± 0.11 vs. 1.25 ± 0.40, P < 0.01) and higher expression of TGF-β1 mRNA (1.10 ± 0.21 vs. 0.82 ± 0.07, P < 0.05).

CONCLUSIONS

EPCs derived from human umbilical cord blood were successfully transplanted into injured vessels. The transplanted EPCs inhibited neointimal hyperplasia and promoted vascular re-endothelialization.

Salvage of the carotid artery with covered stent after perforation with dialysis sheath. A case report

We present a rare case of carotid tear caused by iatrogenic erroneous insertion of a dialysis sheath into the common carotid artery (CCA). This was treated by placement of a covered stent-graft in the CCA over the puncture site. This treatment achieved hemostasis while preserving the carotid artery with good outcome. The technical details are presented and the relevant literature regarding treatment of carotid blowout syndrome is discussed. This case suggests that placement of a covered stent-graft is a good option not only for the "usual" blowout syndrome due to head and neck tumors, but also for treatment of iatrogenic injury to the carotid artery.

Use of onyx for transarterial balloon-assisted embolization of traumatic carotid cavernous fistulas: a report of 23 cases

BACKGROUND AND PURPOSE

TCCFs are a common complication following craniofacial trauma and are usually treated by coils or detachable balloons. The use of the liquid embolic agent Onyx as the sole agent for the treatment of TCCFs has been rarely reported. Herein, we summarized the preliminary experience and effectiveness of treating TCCFs with Onyx in 23 patients.

MATERIALS AND METHODS

From the 36 type A CCFs treated in our department between September 2005 and March 2011, a total of 23 posttraumatic direct CCFs were treated by using Onyx only via transarterial approach.

RESULTS

Immediate postprocedural angiograms demonstrated complete occlusion in all patients. All the patients underwent a single procedure except 1 with bilateral TCCFs. Up to 24-month clinical and 3-month angiographic follow-ups revealed an ongoing complete occlusion without any complications.

CONCLUSIONS

In this series, the use of Onyx for the transarterial embolization of TCCFs was feasible and effective. Associated adverse events were rare.

Life-threatening neurovascular injuries associated with recreational use of "banana" boats

Banana boat rides are a popular form of recreation worldwide. Recommendations that speed should not exceed 15 mph, passengers should wear protective gear, and an observer should be present on the towing boat are generally ignored. Medical personnel at tourist venues and general practitioners may not be attuned to the risk of serious injury. We present our experience in the management carotid- and vertebral artery dissections sustained by 44- and 23-year-old males during banana boat rides. In both cases, the dissections were misdiagnosed until patients presented to the Emergency Department two days after injury. In the first patient, medical management failed and endovascular treatment was required due to neurological deterioration. In patient two, anticoagulation therapy prevented embolic sequelae. Boat operators, passengers, and the medical personnel who are first to see these patients should be aware of the risk of arterial dissection to facilitate early detection of these potentially life-threatening injuries.

[Case of a giant cervical carotid artery aneurysm with contralateral severe stenosis treated using a covered stent]

We report a case of a cervical carotid artery pseudoaneurysm with contralateral severe stenosis, treated using a covered stent. A 79-year-old man admitted for a splenic artery aneurysm presented a pulsatile mass on the right side of his neck and lower cranial nerve palsy after misinsertion of a central venous line into the right carotid artery. MRI revealed a huge thrombosed aneurysm (30 mm×25 mm) in the right common carotid artery (CCA). We planned an aneurysmectomy and CCA interposition with a vascular graft. However the aneurysm continued to expand. We considered that it was difficult to expose the internal carotid artery (ICA) by a direct surgical technique, and therefore carried out placement of a covered stent over the orifice of the aneurysm using an endovascular surgical technique. Following placement of the covered stent, subsequent contrast-enhanced CT revealed leakage of contrast material into the aneurysm. An additional bare stent was placed into the proximal end of the covered stent at 15 days after the initial treatment. Angiography demonstrated no leakage of the contrast material. Following the second treatment, the pulsatile mass was reduced in size. Lower cranial nerve palsy remained but had slightly improved. We described the case of a huge cervical carotid pseudoaneurysm that was successfully treated using a covered stent.

[A case of coil embolization for unexpected massive bleeding caused by internal carotid artery injury]

We experienced a case of coil embolization for unexpected massive bleeding due to the injury of the internal carotid artery during surgery. A 78-year-old woman underwent right maxillectomy for a malignant tumor in the maxilla. Three hours after the start of the operation, uncontrollable bleeding occurred suddenly, with the blood loss reaching 4,600 ml in 10 minutes. Blood pressure decreased precipitously, but systolic blood pressure recovered to 90 mmHg after rapid infusion and transfusion. The bleeding point could not be identified, and hemostasis by gauze compression was tried in vain. After a large amount of fluid replacement in a short period, the hemoglobin concentration decreased to 2.5 g x dl(-1) temporarily. Angiography revealed the injury of the right internal carotid artery. Coil embolization in the internal carotid artery was performed unilaterally for hemostasis. The total blood loss amounted to 28 liters, and the patient received 2,000 ml of albumin solution, 68 units of red cell concentrates and 50 units of fresh frozen plasma in addition to 18,420 ml of lactated Ringer solution. Operation time was 17 hours and 48 minutes. Despite unexpected massive bleeding and hemodilution, maxillectomy was completed and the patient recovered without any postoperative sequelae.

Reconstructive stent-buttressed coil embolization of a traumatic pseudoaneurysm of the supraclinoid internal carotid artery

It is critical that traumatic intracranial pseudoaneurysms should be removed completely from the parent artery because there is a possibility of significant morbidity and mortality from the high risk of rebleeding from any remnants of the pseudoaneurysm. However, the deconstruction of the parent artery has the risk of ischemic damage to the distal to the trapped artery. We describe a case of a successful reconstructive stent-buttressed coil embolization in a patient with a traumatic pseudoaneurysm of the intracranial internal carotid artery. A 30-year-old man with a stuporous mentality was admitted to our institution after a traffic accident. The initial computed tomography scan showed a diffuse subarachnoid hemorrhage and a pseudoaneurysm of the left supraclinoid internal carotid artery. A reconstructive endovascular treatment using stent-assisted coil embolization with a stent-within-a-stent technique was conducted in order to save carotid blood flow. The pseudoaneurysm was completely obliterated and the patient recovered without any neurological deficit. We suggest that multiple stent placements with coiling may be considered as a treatment option for intracranial traumatic pseudoaneurysms as a reconstructive treatment.

Shear stress-induced activation of Tie2-dependent signaling pathway enhances reendothelialization capacity of early endothelial progenitor cells

Although endothelial progenitor cells (EPCs) play a pivotal role in the endothelial repair following arterial injury and shear stress has a beneficial effect on EPCs, however, the molecular mechanism underlying the influence of EPCs on the endothelial integrity and the regulation of shear stress on the EPC signaling remained to be studied. Here, we investigated the effects of laminar shear stress on the tyrosine kinase with immunoglobulin and epidermal growth factor homology domain-2 (Tie2)-dependent signaling and its relation to in vivo reendothelialization capacity of human early EPCs. The human early EPCs were treated with shear stress. Shear stress in a dose-dependent manner increased angiopoietin-2 (Ang2)-induced migratory, adhesive and proliferatory activities of EPCs. Transplantation of EPCs treated by shear stress facilitated in vivo reendothelialization in nude mouse model of carotid artery injury. In parallel, the phosphorylation of Tie2 and Akt of EPCs in response to shear stress was significantly enhanced. With treatment of Tie2 knockdown or Akt inhibition, shear stress-induced phosphorylation of Akt and endothelial nitric oxide synthase (eNOS) of EPCs was markedly suppressed. After Tie2/PI3K/Akt/eNOS signaling was blocked, the effects of shear stress on in vitro function and in vivo reendothelialization capacity of EPCs were significantly inhibited. The present findings demonstrate for the first time that Tie2/PI3k/Akt/eNOS signaling pathway is, at least in part, involved in the EPCs-mediated reendothelialization after arterial injury. The upregulation of shear stress-induced Tie2-dependent signaling contributes to enhanced in vivo reendothelialization capacity of human EPCs.

The use of a covered stent in carotid blowout syndrome

Rupture of the extracranial carotid arteries or their major branches is known as carotid blowout syndrome (CBS). CBS is a well-recognized complication of cancer of the head and neck and subsequent radiation therapy. A few treatment modalities are available, including open ligation and different endovascular techniques, but questions regarding both the immediate and delayed complications of these procedures persist. In this case report, we describe the management of acute CBS in a 54-year-old man who had previously been treated for follicular thyroid carcinoma. The patient was hemorrhaging from a pseudoaneurysm of the left common carotid artery. A self-expanding polytetrafluoroethylene (Teflon) -covered stent was successfully deployed endovascularly, and this resulted in cessation of the bleeding and restoration of flow through the vessel. We examine the covered-stent approach to treating acute CBS, and we discuss other treatment approaches that have been described in the literature.

Cilostazol activates function of bone marrow-derived endothelial progenitor cell for re-endothelialization in a carotid balloon injury model

BACKGROUND

Cilostazol(CLZ) has been used as a vasodilating anti-platelet drug clinically and demonstrated to inhibit proliferation of smooth muscle cells and effect on endothelial cells. However, the effect of CLZ on re-endothelialization including bone marrow (BM)-derived endothelial progenitor cell (EPC) contribution is unclear. We have investigated the hypothesis that CLZ might accelerate re-endothelialization with EPCs.

METHODOLOGY/PRINCIPAL FINDINGS

Balloon carotid denudation was performed in male Sprague-Dawley rats. CLZ group was given CLZ mixed feed from 2 weeks before carotid injury. Control group was fed normal diet. CLZ accelerated re-endothelialization at 2 weeks after surgery and resulted in a significant reduction of neointima formation 4 weeks after surgery compared with that in control group. CLZ also increased the number of circulating EPCs throughout the time course. We examined the contribution of BM-derived EPCs to re-endothelialization by BM transplantation from Tie2/lacZ mice to nude rats. The number of Tie2-regulated X-gal positive cells on injured arterial luminal surface was increased at 2 weeks after surgery in CLZ group compared with that in control group. In vitro, CLZ enhanced proliferation, adhesion and migration activity, and differentiation with mRNA upregulation of adhesion molecule integrin αvβ3, chemokine receptor CXCR4 and growth factor VEGF assessed by real-time RT-PCR in rat BM-derived cultured EPCs. In addition, CLZ markedly increased the expression of SDF-1α that is a ligand of CXCR4 receptor in EPCs, in the media following vascular injury.

CONCLUSIONS/SIGNIFICANCE

CLZ promotes EPC mobilization from BM and EPC recruitment to sites of arterial injury, and thereby inhibited neointima formation with acceleration of re-endothelialization with EPCs as well as pre-existing endothelial cells in a rat carotid balloon injury model. CLZ could be not only an anti-platelet agent but also a promising tool for endothelial regeneration, which is a key event for preventing atherosclerosis or restenosis after vascular intervention.

[Rescue of postoperative carotid blowout in head and neck neoplasms]

OBJECTIVE

To investigate the prevention and rescuing measures of postoperative fatal bleeding induced by carotid blowout in head and neck tumors.

METHODS

Seven cases with postoperative carotid bleeding treated from October 2003 to August 2009 were reviewed retrospectively. Of the patients, 6 were with common carotid blowout and one with internal carotid artery blowout. All patients underwent pre- or post-operative radiotherapy for primary head and neck tumours and 3 patients had neck defect repair with deltopectoral skin flap, frontal flap or free radial arm flap respectively. After carotid blowout bleeding, the patients were treated in time with X ray transcatheter intervention including transcatheter arterial embolization (TAE) and self-expanding covered stent implantation, followed by repairing the carotid region with appropriate myocutaneous flaps.

RESULTS

Of 7 patients with carotid blowout, 5 patients were successfully rescued with X ray transcatheter intervention, of them 2 with self-expanding covered stent implantation and 2 with TAE respectively, and other 2 patients died due to rapid bleeding. Of the successfully rescued patients, 2 patients were with the repair of carotid area by pectoralis major myocutaneous flap, one by submental flap and one by local flap, but another one not with flap repair. Follow-up showed the 3 patients rescued with self-expanding covered stent implantation were survival for 6, 12, and 20 months, respectively, and the 2 patients rescued with TAE died of repeated carotid blowout in 2 and 13 months later, respectively.

CONCLUSIONS

The planned and timely X ray transcatheter intervention is an effective method to treat carotid blowout bleeding in the patients underwent head and neck tumour surgeries. Compared with TAE, self-expanding covered stent implantation may be more reliable for restoring the blood supply of head and neck region, with less complications. One-stage repair of carotid region with myocutaneous flap is of great importance to protect the carotid and to promote the wound healing.

Radiotherapy-induced common carotid pseudoaneurysm presenting with initially occult upper airway hemorrhage and successfully treated by endovascular stent graft

Radiation induced carotid vasculopathy may present as steno-occlusive disease or less commonly as a pseudoaneurysm. The latter most often presents with a pulsatile mass but is a potential cause of life threatening hemorrhage. We present a case of a small common carotid artery (CCA) pseudoaneurysm that was initially dismissed as the cause of the patients presenting epistaxis given its small size and location. After standard bilateral internal maxillary artery embolizations failed to prevent significant subsequent pharyngeal and tracheal blood loss and serial imaging demonstrated a progressive enlargement of the pseudoaneurysm, a stent graft was successfully placed across the lesion. At five months post stenting, follow-up imaging of the neck showed a stable obliteration of the pseudoaneurysm, good arterial patency, and the patient remained free of recurrent hemorrhage. This case demonstrates that even a small carotid pseudoaneurysm, can present with pharyngeal hemorrhage and should be treated aggressively--with endovascular stent grafting being a preferred treatment modality for arterial lesions in the irradiated neck.

The use of arterial closure devices for incidental arterial injury

Incidental arterial injury is one of the main mechanical complications associated with central venous catheter placement. These injuries can result in significant morbidity and mortality. The use of arterial closure devices to repair these injuries offers a less invasive alternative than open repair and a safer approach than manual compression. We present 3 cases of critically ill patients treated with arterial closure devices when attempted central venous catheterization failed and inadvertent arterial cannulation occurred. A brief review of the various closure devices and there indications is discussed.

[Therapeutic management for iatrogenic injury of great arteries during transnasal surgery of tumors of the hypophysis]

Results of clinical examination and surgical treatment of 1022 patients with tumors of the hypophysis were analyzed. All the patients were operated upon by transsphenoidal endoscopic approach during the recent 10 years. Complications were observed in 76 (7.4%) patients. Most serious of them were: intraoperative mechanical injury of the right internal carotid artery and contact rupture of a large aneurysm of the internal carotid artery falsely diagnosed as craniopharyngioma. In both cases urgent intravascular interventions were necessary which resulted in relief of symptoms and recovery of the patients.

Endoscopic endonasal surgery complication: new methods of intracavernous internal carotid artery injury treatment

OBJECTIVES

To present new interventional neuroradiology methods of management of an ICA injury during functional endoscopic sinus surgery (FESS).

CASE

The authors report the case of a patient who presented an ICA injury during a FESS and who could undergo an embolization. This embolization stopped the epistaxis and saved the patient from a lethal issue without any aftereffect.

DISCUSSION

After a review of the literature the authors describe the circumstances of occurrence, the urgent management and the modern treatment of an ICA injury. Along with the progress in neuroradiology, the embolization represents a top grade treatment of this complication. Embolization with stent keeps permeable the ICA axis which represents a major progress in the management.

CONCLUSION

The success of the management of an ICA injury relies on the close collaboration between anesthesist, otorhinolaryngologist surgeon and interventional neuroradiologist. Since 2004, modern techniques of interventional neuroradiology using new stents allow to keep permeable the ICA axis.

Inhibition of MMP-2 gene expression with small interfering RNA in rabbit vascular smooth muscle cells

Matrix metalloproteinase-2 (MMP-2) is constitutively expressed in vascular smooth muscle cells (VSMCs). Using small interfering RNA (siRNA), we evaluated the effect of MMP-2 inhibition in VSMCs in vitro and ex vivo. Rabbit VSMCs were transfected in vitro with 50 nmol/l MMP-2 siRNA or scramble siRNA. Flow cytometry and confocal microscopy showed cellular uptake of siRNA in ∼80% of VSMCs. MMP-2 mRNA levels evaluated by real-time RT-PCR, pro-MMP-2 activity from conditioned culture media evaluated by gelatin zymography, and VSMC migration were reduced by 44 ± 19%, 43 ± 14%, and 36 ± 14%, respectively, in MMP-2 siRNA-transfected compared with scramble siRNA-transfected VSMCs ( P < 0.005 for all). Ex vivo MMP-2 siRNA transfection was performed 2 wk after balloon injury of hypercholesterolemic rabbit carotid arteries. Fluorescence microscopy showed circumferential siRNA uptake in neointimal cells. Gelatin zymography of carotid artery culture medium demonstrated a significant decrease of pro-MMP-2 activity in MMP-2 siRNA-transfected compared with scramble siRNA-transfected arteries ( P < 0.01). Overall, our results demonstrate that in vitro MMP-2 siRNA transfection in VSMCs markedly inhibits MMP-2 gene expression and VSMC migration and that ex vivo delivery of MMP-2 siRNA in balloon-injured arteries reduces pro-MMP-2 activity in neointimal cells, suggesting that siRNA could be used to modify arterial biology in vivo.

Urgent Endovascular Covered-Stent Treatment of Internal Carotid Artery Injury Caused by a Gunshot

Penetrating non-lethal injuries to the distal extra-cranial internal carotid artery are often a surgical challenge, because of the difficulty of direct exposure and repair of the internal carotid artery at the skull base. We describe a case of a successful emergency treatment, with an endovascular procedure using a PTFE covered-stent, of an internal carotid artery haemorrhagic pseudoaneurysm following penetrating trauma to the neck by single gunshot.

Stentgraft-implantation for treatment of internal carotid artery injury during endonasal sinus surgery

BACKGROUND

Damage of the internal carotid artery (ICA) is very rare but can be a dramatic complication of endonasal sinus surgery. In the literature only a few cases are reported, some of them with fatal results.

METHODS

We present two cases with massive bleeding of the ICA caused by endonasal sinus surgery.

RESULTS

In both cases bleeding could be stopped sufficiently by implanting a stentgraft.

CONCLUSION

The lumen of the artery could be preserved and no neurological deficits were observed.