Anastomosis Of Carotid Artery Research Articles

Cadaveric Feasibility of Robotic-Assisted Radial Artery-Internal Carotid Artery-Middle Cerebral Artery Anastomosis for Neurovascular Surgery.

To the best of our knowledge, this is the first reported cadaveric feasibility study of leader-follower type robotic-assisted middle cerebral artery (MCA)-radial artery-internal carotid artery anastomosis in the neurovascular surgery field using the da Vinci Xi system (da Vinci Surgical System; Intuitive Surgical, Inc.). Vascular suturing is a necessary skill in neurosurgery; however, the learning curve for deep and high-flow bypasses is severely low. Thus, robot-assisted surgery has been introduced. Here, we describe the surgical workflow adaptations of vascular anastomosis using the da Vinci system to assess the feasibility of robot-assisted anastomoses of the radial and middle cerebral arteries. Two fresh cadaver heads were studied using the da Vinci Xi Surgical System with 0° and 30° stereoscopic endoscopes to visualize the neuroanatomy. The da Vinci Xi Surgical System was used throughout the anastomosis of the MCA and intracarotid artery. The optic nerve, optic chiasm, carotid artery, and oculomotor nerve were visualized using standard microdissection techniques. The Sylvian fissure was exposed from the proximal Sylvian membrane to the distal MCA. Using black diamond microforceps and Potts scissors, suturing was achieved on the radial artery-middle cerebral artery using 8-0 Prolene and on the radial artery-internal carotid artery using 7-0 Prolene. A bypass of the MCA-radial artery-internal carotid artery can be achieved using the da Vinci Xi Surgical System in cadaver models. This system provides experts and less experienced neurosurgeons with stable bypass techniques for both superficial and deep-seated arteries. However, further studies are needed to evaluate the safety and benefits of the da Vinci Xi Surgical System for bypass procedures.

Experimental Broad-Based Curved Sidewall Aneurysms in Rabbits Mimicking Human Carotid Siphon Aneurysms: Proof of Feasibility and Comparability Using Computational Fluid Dynamics

Broad-based sidewall aneurysms of the carotidartery are primarily treated endovascularly. However,recurrence or rupture after treatment still poses a significant risk. Hence, reliable animal models mimicking this aneurysm type are essential for to evaluate the performanceof new advanced endovascular devices. Experimental aneurysms were created in 12 New Zealand white rabbits (2.5-3.5 kg). The human carotid siphon was mimicked with an end-to-end anastomosis of both common carotid arteries. A venous pouch was sutured on the convexity to mimic a broad-based side wall aneurysm. Patency and configuration were investigated 4 weeks postoperatively by 3-T magnetic resonance angiography. To compare flow conditions of broad-based sidewall aneurysms in rabbits and humans, exemplary computational fluid dynamics simulations were performed using species-specific blood viscosity values. We were able to achieve 0% peri- or postoperative mortality. Patency was confirmed by 3-T magnetic resonance angiography in 11 of 12 aneurysms (91.7%). Aneurysm lengths ranged from 6.4 to 9.8 mm and aneurysm necks from 7.3 to 9.8 mm. Computational fluid dynamics showed simple flow profiles with one vortex in rabbit as well as in human aneurysms. Wall shear stress rates were comparable using species-specific blood viscosity values (rabbit mean 1.65 Pa vs. human mean 1.7 Pa). The broad-based curved sidewall aneurysm model mimicking the carotid siphon showed high aneurysm patency rates with low morbidity. High comparability with human flow patterns and human intranaeurysmal biomechanical forces was shown using simulations.

An arteriovenous fistula model: Carotid artery-posterior facial vein fistula in rats.

To describe an alternative arteriovenous fistula (AVF) model involving anastomosis of the common carotid artery (CCA) with the posterior facial vein (PFV). Twenty-two male Sprague-Dawley rats (age 6-8 weeks) were used to establish the AVF model involving end-to-side anastomosis of PFV and CCA. The peak velocity of the CCA and the diameter of the outflow vein were recorded at 7, 14, and 42 days after the operation using Doppler ultrasound. Pathological examination of the intimal lesions was performed at 14 and 42 days after operation. One rat died within 24 h after surgery related to anesthesia. The patency rates at days 7, 14, and 42 were 85.7%, 81%, and 81%, respectively. The diameter of the carotid artery in rats is approximately 0.8 mm. The diameter of the outflow vein was increased by 1.7-fold and 2.2-fold at 7 days (1.1 ± 0.118 mm) and 14 days (1.4 ± 0.073 mm). At 42 days (1.96 ± 0.101 mm) after operation, the diameter was 3-fold greater compared to the unoperated control rat. The peak systolic flow velocity of the carotid artery at 7 days (593 ± 17.36 mm/s) and 14 days (767 ± 13.64 mm/s) after surgery was significantly greater compared to the control rat (314 ± 15.13 mm/s). The rate of increase was fastest at 7 days and leveled off from 14 to 42 days (875 ± 26 mm/s) after surgery. At 14 days, the intima area showed a nearly 50-fold increase (230 ± 9.93 μm2 × 103) compared to control (area 5 ± 0.37 μm2 × 103). Comparing 6 weeks with 2 weeks (280 ± 10.54 μm2 × 103) after surgery, the intima area increased 1.2 times. The CCA-PFV fistula in rats is a viable alternative AVF model.

Ruptured pial-pial collateral aneurysm associated with left internal carotid artery occlusion: nuances of surgical management. Illustrative case.

Carotid occlusion often leads to the formation of a collateral network. On rare occasions, due to hemodynamic influence, aneurysms can occur. Here, the authors describe a 69-year-old male presenting with intracerebral hemorrhage secondary to a ruptured aneurysm within such a network. The patient presented to the emergency department with an altered level of consciousness. Imaging showed a left temporal lobe hemorrhage extending into the ventricle, subdural hematoma, and evidence of contrast extravasation. Digital subtraction angiography revealed an occluded left internal carotid artery with the left middle cerebral artery territory reconstituted by flow through an external carotid artery-internal carotid artery anastomosis. The latter was formed by the superficial temporal artery-superior orbital artery, as well as pial-pial collaterals from the posterior temporal artery. Notably, a 4-mm aneurysm arising from the pial-pial collateral network was identified. Surgical intervention involved a left temporal craniectomy and aneurysm excision, with special attention paid to preserving the anastomotic flow through the superficial temporal artery. This case underscores the importance of recognizing and preserving collateral vascular pathways in cases of carotid occlusion with an associated aneurysm. It emphasizes the necessary balance between managing aneurysm risk and maintaining cerebral perfusion, highlighting the need for careful preoperative planning and intraoperative caution.

A microscope in your pocket: can smartphones be used to perform microsurgery?

To evaluate the use of the latest generation smartphone camera in performing arterial microanastomosis in rats. Ten Wistar rats were divided into 2 groups and underwent anastomosis of the right carotid artery with the aid of magnification from a microscope (group M) and a smartphone camera (group S), to compare patency in 72 hours, as well as to measure the weight of the animals, diameter of the carotid arteries and anastomosis time. There was no statistical difference between the weight of the animals or the diameter of the carotid arteries. There was a statistical difference for the time spent on anastomoses, which was greater in group S, with higher rates of thrombosis (p < 0.05). Although our patency and anastomosis time results were statistically lower in the smartphone group, there was success in some cases. As the segment continues to progress, it is likely that the results will improve in line with the evolution of camera technology.

High Altitude Head and Neck Paragangliomas: A First Sub-Himalayan Experience.

High-altitude natives have a high incidence of parangangliomas (PGL) of the head and neck, especially the carotid body tumor. The aim of this study is to describe the clinical presentation, pattern, altitude of residence, distribution, management, and follow-up of head and neck paragangliomas (HNPGL) in our sub-Himalayan population. Retrospective cohort study. Academic tertiary care hospital. Hospital records of 20 patients of HNPGL diagnosed from December 2017 to December 2021 were retrieved for analysis. Twenty patients with 23 HNPGL, with a mean age of 41.74 years were managed in our institute. The female-to-male ratio was 2.3: 1 and the mean follow-up was 29.95 months. Nine had carotid body (CBPGL), 7 had tympanic (TPGL), 2 had jugular (JPGL), and 2 had vagal paragangliomas (VPGL). Multiple PGL were seen in 4 patients (20%). Majority of cases (all CBPGL and 57.14% of TPGL) were residents of the high altitude, and the rest were from the low altitude. Fifteen patients (8 CBPGL, 7 TPGL) were operated. There were no major complications except in a patient with large carotid body tumor required anastomosis of carotid artery. Five patients received stereotactic radiotherapy, and 1 malignant PGL received chemoradiotherapy. In this study, JPGL and VPGL are common at low altitudes, whereas carotid body and tympanic PGL were the most common tumor at high altitudes. Being a retrospective and study small sample size, a definite conclusion is not established, however, a genetic analysis and inclusion of a wider population in a future prospective study may establish the hypothesis.

Abstract 097: Un‐stumped by Carotid Stump Syndrome: Use of External Carotid Stenting in Preventing Ischemic Stroke

Introduction Recurrent infarcts to the internal carotid artery territory in the setting of a corresponding occlusion raises concern for carotid stump syndrome. Over time, robust anastomoses may develop between the patent ipsilateral external carotid artery and the anterior circulation distal to the site of occlusion. A carotid stump’s disturbance of flow uncommonly can form emboli that travel via retrograde flow from the occluded internal carotid artery to the ipsilateral external carotid artery and its collaterals. Stenosis of the external carotid artery in such patients can be a source of atheroembolism or hypoperfusion. We describe a case of external carotid stenting with carotid stump coil occlusion. Methods We present a case report. Verbal consent to share this information was obtained directly from the patient. Results A 75‐year‐old man with aortic stenosis, atrial arrhythmia, multiple prior bi‐hemispheric strokes, on aspirin and clopidogrel, presented with left facial droop, arm weakness, and slurred speech. Magnetic resonance imaging revealed embolic appearing strokes in the right middle cerebral artery territory (Figure 1A). Cerebral angiography revealed complete occlusion of the right internal carotid artery with perfusion of the right middle cerebral artery by external carotid artery anastomoses, and the external carotid was found to be stenosed proximally. Digital subtraction angiography revealed right external carotid – middle cerebral artery anastomoses via the right sphenopalatine artery, middle meningeal artery, internal maxillary artery, and ophthalmic collaterals (Figure 1B). The patient underwent coiling of the right internal carotid artery stump (Figure 1C) followed by stenting of the right external carotid using a 9 mm x 40 mm Cordis precise Pro stent. Post‐stenting angiogram demonstrated good apposition of the stent to the parent vessel walls and improvement of flow into the right external carotid and intracranial circulation (Figure 1D). The patient was treated with aspirin and ticagrelor for 3 months. Repeat imaging at follow up did not show further embolic episodes, with improvement in the patient’s deficits. After three months, he was continued on aspirin alone. Conclusion In patients with an occluded internal carotid artery and recurrent embolic infarcts ipsilateral to the side of the occlusion, carotid stump syndrome may be considered. In this case, we believe the patient’s carotid occlusion served as a nidus for emboli formation, or that there was atheroembolism from the stenosed external carotid artery despite adherence to dual antiplatelet therapy. By coiling the stump, we addressed a possible source of emboli, and stenting of the proximal external carotid optimized anterograde flow and prevented further atheroembolism. Our case showcases an interventional neuroradiology approach to carotid stump emboli and external carotid artery stenosis.

A case of surgical treatment of an aneurysm of the internal carotid artery with severe angulation

The leading role among causes of CVA (cerebrovascular accident) is occupied by pathology of the internal carotid artery. The most common etiological factor is a pronounced atherosclerotic process in the area of carotid artery bifurcation. Significantly less common factors are non-atherosclerotic causes of internal carotid artery disease, which include aneurysm and pathological tortuosity. Their combination significantly increases the risk of cerebral events, which requires timely surgical treatment. Surgical treatment is associated with certain intraoperative difficulties. The following is a clinical case of surgical treatment of an aneurysm of the internal carotid artery extracranial segment in combination with its deformation correlated with hemodynamic stenosis of more than 70%. A resection of the tortuosity-aneurysm complex with the formation of an end-to-end anastomosis of the internal carotid artery was performed.

Total aortic arch replacement without deep hypothermic circulatory arrest in type A aortic dissection: Left axillar artery for arterial cannulation

ObjectiveTotal aortic arch replacement (TAR) necessitates hypothermic circulatory arrest (CA). The frozen elephant trunk technique (FET) additionally requires commercial hybrid grafts. Herein we describe a novel modified FET technique without CA using standard grafts thanks to left axillary artery (LAxA) cannulation in patients with acute type A aortic dissection. MethodsLAxA anastomosis is made first using a homemade debranching graft, and cardiopulmonary bypass is initiated, followed by anastomoses of left common carotid and innominate arteries. The rest of the operation is performed with complete cerebral perfusion. Following replacement of ascending aorta/root, cardiac reperfusion is started using a root cannula which continues throughout the procedure. Distal arch anastomosis is performed clamp-on, allowing lower body perfusion via left subclavian artery. Lower body perfusion is interrupted for 5 to 8 minutes to deploy an endograft to complete a modified FET. Following cannulation of distal arch graft, perfusion of distal aorta is restarted, and all three grafts are incorporated to construct a neo-ascending aorta and arch. ResultsBetween December 2018 and May 2022, 38 patients underwent TAR without operative mortality. Hospital mortality was %15.7, and spinal cord ischemia and stroke were not encountered in surviving patients. The mean lower body CA time was 7.2 ± 2.8 minutes. ConclusionsTAR using standard endografts without CA is possible with LAxA cannulation. To perform a FET, only a short interruption of lower body circulation is sufficient to deploy an endograft, also improving hemostasis of distal anastomosis. Further studies are required with a higher number of patients to evaluate the efficiency of this novel technique.

Inhibitory effect of cilostazol on intimal hyperplasia and smooth muscle cell proliferation in a rabbit carotid artery anastomosis model

Objectives: This study aims to investigate the effect of cilostazol on intimal hyperplasia and smooth muscle cell proliferation in a rabbit carotid artery anastomosis model. Materials and methods: A total of 16 New Zealand male rabbits weighing 2 to 3 kg were used in this study. The rabbits were divided into two groups with eight in each group as Group A and Group B. A vertical neck incision was made in an appropriate position for all group rabbits and the right carotid artery was dissected. The same artery was transected and anastomosis using 8/0 polypropylene was performed with a continuous anastomosis technique. Group A was assigned as the control group and no medication was given. Cilostazol was administrated to Group B at a dose of 25 mg/kg twice a day per oral for 21 days. At the end of Day 21, the anastomosis segments of the right carotid artery and contralateral carotid artery of all rabbits were sent to the histology laboratory for analysis. The lumen diameter, lumen area, intimal area, medial area, and intima/media area ratio were estimated. Results: In the serial sections, the mean lumen diameter of Group B was found to be significantly higher than Group A (p=0.001). The lumen area of Group B was significantly higher than Group A (p=0.001). The section series were evaluated and the area of the intima of Group B was significantly lower than Group A (p=0.001). The medial area of Group B was significantly larger than Group A (p=0.001). The intima/media area ratio was significantly higher in Group A (p=0.001). Conclusion: Cilostazol may be useful for preventing intimal hyperplasia and smooth muscle cell proliferation after vascular surgery.

SP34. Development of Sutureless Vaso-Lock for Vascular Anastomosis

PURPOSE: Micro- and macrovascular anastomoses involve suturing together of blood vessels, which is a critical foundational surgical skill. However, it faces many challenges, such as decade-long training and inherent dexterity of the surgeon. Procedures are long and expensive, require specialized operating rooms and equipment, making them prohibitive in many hospitals. Our team has created a unique anastomotic device, Vaso-Lock, as a sutureless coupler. Vaso-Lock is intraluminal, holding free vessel ends together with traction by anchors. We aim to apply Vaso-Lock to change the paradigm of surgical training and practice, and improve technical capabilities for vascular anastomosis. METHODS: We have utilized 3D-printing to prototype Vaso-Locks with quick design adjustments. Vaso-Lock maintained its intact structure after ethylene oxide sterilization, which was evaluated by scanning electron microscope. Vaso-Lock was deployed in a porcine model for anastomosis of common carotid artery and internal jugular vein. Doppler ultrasound was used to longitudinally assess patency, blood flow velocities, and lumen preservation. Histological studies were performed to evaluate endothelialization and device-vessel interface biocompatibility. RESULTS: Vaso-Lock maintained anastomosis of common carotid artery to internal jugular vein in 3 porcine, with no evidence of leakage after deployment. Doppler ultrasonography demonstrated the mixture of arterial and venous blood inside the Vaso-Lock. During the extraction of Vaso-Lock, no blood clots were identified at the anastomosis site. Guidewire went through the explanted blood vessels anastomosed by the Vaso-Lock without resistance. In terms of histological analysis, we performed four types of staining: H&E, Masson’s Trichrome (blue for collagen), Verhoeff-Van Gieson (black for elastin), and Alizarin Red (red for calcium). All tissue sections with Vaso-Locks displayed open lumen at the anastomosis site. Inflammation cells, along with collagen bundles, appeared around anchors of the Vaso-Lock. Calcium was identified around the Vaso-Lock at 2-week. Intimal growth occurred under the Vaso-Lock at 6-week. We are examining the effect of Vaso-Lock on cellular structure of the blood vessel by immunohistochemistry. We are also evaluating heparinized Vaso-Lock in terms of its long-term patency and biocompatibility. CONCLUSIONS: Vaso-Lock maintained patency at least 6 weeks for arteriovenous anastomosis along with a natural healing response in a porcine model. This novel device will dramatically enhance the efficiency with an assortment of micro- and macrovascular anastomoses ranging from tissue flaps to arteriovenous fistula creations, making anastomosis globally available.

Intraoperative Neuromonitoring of Hypoglossal Nerves Using Transcranial and Direct Electrical Stimulation During Extracranial Internal Carotid Artery Surgery.

We explored whether the electromyogram (EMG) and the motor evoked potential (MEP) are useful for monitoring the function of the hypoglossal nerve during surgery targeting the cervical segment of the internal carotid artery. The present study included 6 patients with internal carotid arterial stenosis (1 patient underwent bilateral surgeries) and 1 patient with a cervical carotid artery aneurysm. In 5 of the 8 procedures, the EMGs were recorded. We examined whether changes in the MEP and/or EMG were capable of predicting postoperative hypoglossal nerve deficits. None of the 6 patients who underwent a total of 7 carotid endarterectomy (CEA) procedures experienced postoperative hypoglossal nerve morbidity. In 2 of the 7 procedures, the MEP disappeared or decreased significantly during CEA. In all 4 cases in which the hypoglossal nerve was directly stimulated during CEA, stable and reproducible EMGs were obtained throughout the manipulation of the internal carotid artery. Hypoglossal nerve morbidity was observed in the one case that underwent aneurysm removal and end-to-end anastomosis of the internal carotid artery. In this case, while the MEP decreased significantly during the operation, the EMG showed true-positive results and false-negative results, depending on the stimulation site. The monitoring of hypoglossal nerve function using EMG appears to be accurate if an appropriate stimulation site is selected. Hypoglossal nerve monitoring using MEP can produce false-positive results. Combined monitoring using both MEP and EMG is recommended in cases where exposure of the hypoglossal nerve is expected to be technically difficult.

Abstract Number ‐ 56: Investigation of Aneurysmal Initiation Factor with Experimental Animal Model by Computational Fluid Dynamics Analysis

Introduction Hemodynamics has been reported to be involved in the pathophysiology of the initiation of intracranial aneurysms. Computational fluid dynamics (CFD) simulation has been widely used to investigate what kind of hemodynamics is related to intracranial aneurysm development or rupture. However, in the case of humans, it is difficult to obtain cerebrovascular images before the aneurysm formation because most of them are detected incidentally by magnetic resonance angiography (MRA) or computed tomography angiography (CTA). Therefore, the mechanism of aneurysm initiation has not been elucidated yet. In this study, CFD analysis was conducted with experimental animal models. Furthermore, immunostainings and Elastica van Gieson (EvG) staining were also performed to investigate the relationship between hemodynamics and aneurysm initiation. Methods We selected the experimental aneurysm model of a rat proposed by Shimizu et al.[1] With this model, aneurysms can be induced with a certain probability at the artificial bifurcation site created by end‐to‐side anastomosis of bilateral common carotid arteries and induced hypertension. Among the 50 rats surgically manipulated, 5 de novo cases and 14 cases without aneurysm initiation defined as stable cases were included in this study. The other 31 cases were excluded because of death or lack of imaging quality. MRA was conducted weekly until 4 weeks after manipulation. Acquired images were processed for the CFD analysis and various kinds of hemodynamic parameters were calculated. Among them, we regarded dimensionless wall shear stress divergence (WSSD*) and pressure loss coefficient (PLc) as the hemodynamic parameters previously suggested to be related to aneurysm initiation[2]. Vessels were collected after 2 weeks of follow‐up, and we observed endothelial cells (EC), smooth muscle cells (SMC), and the internal elastic lamina (IEL) at the apex of the bifurcationby immunostaining and EvG staining. Results The CFD results showed that a high WSSD* area existed at the apex of bifurcation in both de novo cases and stable cases. The averaged WSSD* of the de novo cases was 18.2% higher than that of the stable cases (de novo: 0.577 ± 0.243, stable: 0.488 ± 0.235). Likewise, the average PLc of the de novo cases was 11.5% higher than that of the stable cases (de novo: 8.22 ± 1.76, stable: 7.37 ± 2.49). The immunostaining images demonstrated that EC and SMC were more degenerated in de novo cases than in stable cases. Furthermore, the EvG staining images showed that IEL degenerated only in the de novo cases. Therefore, because WSSD* and PLc indicate a stretching force and flow impingement on the vessel wall, respectively, the elevation of those parameters may contribute to damage of EC, SMC, and IEL known as pathological features of an intracranial aneurysm. Conclusions CFD analysis and tissue observation were conducted with the vessels of the experimental animal model (5 de novo cases and 14 stable cases). Our results indicate that high WSSD* and high PLc are the factors related to aneurysm initiation.

Persistent trigeminal artery incidentally found in a patient with brain posterior system infarction: a rare case report

The persistent trigeminal artery (PTA) is a persistent, primitive, embryonic anastomosis that provides the blood flow between the vertebro-basilar system and the carotid system. The presence of PTA anastomosis may create an advantage by providing collateral circulation during a stroke as in cases of leptomeningeal collaterals, external-internal carotid artery anastomoses, and the polygon of Willis. However, patients with this variation are more susceptible to the development of non-occlusive posterior arterial system infarction when they experience hypotension attacks. In the literature, there are only few case reports on non-occlusive posterior system infarction associated with PTA variation. In this case report, we present to an 81-year-old patient with posterior system infarct findings and persistent trigeminal artery variation.

Perfusion management of arch-clamping technique in total arch replacement with frozen elephant trunk.

A technique called arch-clamping was used at our institute to ensure perfusion of the lower body and brain during total arch replacement with frozen elephant trunk (TAR and FET). The aortic arch clamp is inserted between the left common carotid artery and the left subclavian artery after inserting the stented elephant trunk into the true lumen of the descending aorta during the procedure, and then clamps the aorta and graft together as the distal anastomotic edge of the aorta. After the arch clamp was in place, lower body perfusion was resumed through the femoral artery was resumed and time to circulatory arrest was reduced to approximately 4 min. Cardiopulmonary bypass (CPB) flow was gradually restored to full rate. Thereafter, the left carotid artery anastomosis was completed and rewarming began. Finally, during the rewarming period, other branches of the aortic arch and ascending aorta were reconstructed. In this paper, we describe the perfusion management strategy, discuss intraoperative monitoring parameters, and examine the feasibility of the technique from a perfusion perspective.

Pentoxifylline decreases the activity of the nucleotide-binding oligomerization domain-like receptor protein 3 pathway: potential role for preventing arteriovenous fistula stenosis.

This study aimed to determine the effect of pentoxifylline (PTX) on the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome pathway and its role in preventing arteriovenous fistula (AVF) failure. Vein samples were collected from AVF failure patients and from patients who underwent surgical AVF as a control. The expressions of CD34 and NLRP3 in AVF tissues were detected by immunohistochemistry and Western blotting. Arteriovenous fistula rat models were established by the end-to-end anastomosis of the common carotid artery and external jugular vein. The AVF models were divided into the following groups: AVF, AVF + PTX, AVF + uraemia and AVF + uraemia + PTX. Six weeks after surgery, the AVF tissues in each group were collected to detect the expressions of CD34, NLRP3, caspase-1 and interleukin (IL)-1β by immunohistochemistry, Western blotting and real-time polymerase chain reaction. The expressions of NLRP3 and CD34 in human AVF failure tissues were significantly higher than those in normal veins (p < 0.001), indicating that NLRP3 was upregulated in patients with AVF failure. In our animal study, the veins in the AVF + uraemia group exhibited heavy hyperplasia, and the boundary between the media and the adventitia was not clear. However, PTX alleviated this hyperplasia. Compared with the AVF models, the AVF + uraemia models had much higher expressions of NLRP3, caspase-1, IL-1β and CD34 (p < 0.001). However, PTX had the opposite effect against uraemia on the NLRP3 inflammasome pathway at both the gene and protein levels. Our findings provide new insights that show that PTX can decrease the activity of the NLRP3 inflammasome pathway in AVF models. Pentoxifylline has the potential as a drug for preventing intimal hyperplasia and AVF failure.

Imaging features of adult moyamoya disease patients with anterior intracerebral hemorrhage based on high-resolution magnetic resonance imaging

This study aimed to identify the high-resolution magnetic resonance imaging (HRMRI) features of moyamoya disease (MMD) patients with anterior intracerebral hemorrhage (ICH) and attempted to reveal potential mechanisms of anterior ICH. Eligible adult MMD patients were consecutively included, and the morphological features of lenticulostriate arteries (LSAs), vessel wall structure of terminal internal carotid artery (ICA) and periventricular anastomosis were evaluated by HRMRI. 78 MMD patients containing 21 patients with anterior ICH, 31 ischemic patients and 26 asymptomatic patients were included. The mean value of total length of LSAs in anterior ICH group (90.79 ± 37.00 mm) was distinctively lower (p < 0.001) compared with either ischemic group (138.04 ± 46.01 mm) or asymptomatic group (170.50 ± 39.18 mm). Lumen area of terminal ICA was significantly larger (p < 0.001) in hemorrhagic group (4.33 ± 2.02 mm2) compared with ischemic group (2.29 ± 1.17 mm2) or asymptomatic group (3.00 ± 1.34 mm2). Multivariate analysis revealed the total length of LSAs (OR 0.689, 95%CI, 0.565–0.840; p < 0.001) and lumen area of terminal ICA (OR 2.085, 95%, 1.214–3.582; p = 0.008) were significantly associated with anterior ICH. Coexistence of reduced LSAs and relatively preserved lumen area of terminal ICA with an AUC of 0.901 (95%CI, 0.812–0.990) could be a potential predictor of anterior ICH in MMD patients.

Abstract 473: Cilostazol Decreases Venous Outflow Inflammation And Improves Avf Patency Inmurine Arteriovenous Fistula

Background: Arteriovenous fistula (AVF) have high failure rates, and no pharmacotherapeutics can improve AVF patency. The most common cause of AVF failure is inflammation-driven neointimal hyperplasia and thrombosis. Limited observational data suggests that cilostazol (CIL), an FDA-approved phosphodiesterase-3 inhibitor that inhibits platelet activation and smooth muscle cell proliferation, could help improve AVF maturation. Here, we investigated the effects of cilostazol on murine AVF patency, and further assessed the fibrinogenesis and anti-inflammatory effects using intravital fluorescence molecular imaging. Methods: One week prior to fistula creation, mice were randomized to CIL (40mg/kg/day) or PBS group (n=20 each). AVF was created using an end-to-side external jugular vein and carotid artery anastomosis. AVF blood flow was measured post-operatively (Transonic) and then every 7 days until AVF was occluded (&lt;0.1 ml/min). Macrophages and fibrin were imaged after 10mg/kg FMX-AF555 and/or 4.5nmol FTP11CyAm7 i.v. injection prior to imaging on day 7 or day 14, respectively. The target-to-background ratio (TBR) was calculated as mean signal intensity (MSI) of the fistula divided by the MSI of the contralateral vein. Results: Post-operative AVF blood flow was similar between CIL and PBS treated groups (p=0.3). Average AVF patency was significantly longer in CIL group compared to PBS group (42 vs 21 days, p&lt;0.01, figure 1A). Both day 7 and day 14 venous outflow fibrinogenesis signal assessed by IVM was significantly lower in CIL group compared to PBS group (ps&lt;0.05, Figure 1B). On day 14, CIL significantly lower venous outflow FMX signals compared to PBS group (p&lt;0.05). Conclusion: Oral cilostazol therapy prolongs AVF patency, and decreases venous outflow inflammation and fibrinogenesis in experimental AVF in vivo. The current data supports investigating cilostazol as a clinical pro-AVF patency pharmacotherapeutic strategy in dialysis patients.

The effect of bovine serum albumin-glutaraldehyde and polyethylene glycol polymer on local tissue reaction and inflammation in rabbit carotid artery anastomosis.

In addition to the hemostatic properties of hemostatic agents, the investigation of their immunogenic properties, their local effects on application area has been the subject of many experimental studies. There are limited data on the inflammatory effects of Bovine serum albumin-glutaraldehyde and Polyethylene glycol polymer. Therefore, we investigated the effects of these agents on tissue reactions and inflammation in rabbit carotid artery anastomosis in our experimental study. Twenty-one New Zealand male rabbits were randomly divided into three groups. The right carotid artery anastomosis was performed on the control group after transection. Hemostatic agents were applied locally to other two groups separately after transection and anastomosis. At the end of 28days, the type of inflammation, inflammatory cell infiltration, degree of inflammation, and amount of residual adhesives were examined and compared statistically. Cell infiltrations associated with inflammation on the anastomosis site (eosinophils, epithelioid/giant cells, lymphocytes, and plasma cells) and inflammation grade in the groups of hemostatic agents were significantly lower compared to the control group (p < .05). There was no difference between the hemostatic agents. While mild inflammation (61.9%) was dominant in the groups of hemostatic agents, moderate inflammation (85.7%) was more common in the control group. No severe inflammation was observed in any of the three groups. Residual sealant grade between hemostatic agents did not differ significantly. When inflammation and tissue reactions of the 4th week were evaluated, it was determined that both hemostatic agents did not cause severe inflammation. However, comparative results at multiple time intervals are needed due to the dynamic process of inflammation.

The Transcriptional Landscapes and Key Genes in Brain Arteriovenous Malformation Progression in a Venous Hypertension Rat Model Revealed by RNA Sequencing.

BackgroundBrain arteriovenous malformations (bAVM) are abnormal vascular lesions characterized by direct connections between arteries and veins without an intervening capillary bed. The primary goal for brain AVM treatment is to prevent rupture and hemorrhage; however, the underlying molecular mechanisms are still unknown.MethodsWe constructed venous hypertension (VH) rat model with end-to-end anastomosis of the proximal left common carotid artery and the left distal external jugular vein. Thirty-eight adult rats were randomly assigned to four groups: the 0-week (n=5), the 1-week VH group (n=12), the 3-week VH group (n=9), and the 6-week VH group (n=12). We measured the hemodynamics and diameter of the arterialized veins. An RNA sequencing of arterialized veins was conducted, followed by comprehensive bioinformatics analysis to identify key genes and biological pathways involved in VH progression. The candidate genes from RNA-Seq were validated by RT-qPCR and immunostaining in human tissues.ResultsWe observed high-flow and low resistance characteristics in VH models. A total of 317 upregulated and 258 downregulated common genes were consistently differentially expressed during VH progression. Thirteen co-expression modules were obtained by WGCNA analysis, and 4 key modules were identified. Thirteen genes: Adamts8, Adamtsl3, Spon2, Adamtsl2, Chad, Itga7, Comp, Itga8, Bmp6, Fst, Smad6, Smad7, Grem1, and Nog with differential expressions were identified using the density of maximum neighborhood component (DMNC) algorithm in Cytohubba. The expression of five potential genes (Adamts8, Adamtsl3, Spon2, Adamtsl2, Itga8) were increased in RT-qPCR, while in human bAVM tissue, the protein levels of Adamtsl2 and Itga8 were significant elevated and Spon2 and Adamtsl3 were decreased.ConclusionThe identified gene networks of Adamtsl3, Spon2, Adamtsl2, and Itga8 provided key genes for further intervention.