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A , Intraoperative photograph showing a ligated carotid artery with a spacer on the external surface of the artery. This spacer was subsequently removed, leaving a tight stenosis, but not occlusion. B , Angiogram showing a partially ligated artery with approximately 80% stenosis immediately after the procedure. C , Angiogram obtained 3 months after the procedure. Note luminal narrowing proximal and extensive dilation distal to the surgically created stenosis.
Source publication
Limited availability of a large animal model of carotid atherosclerosis has limited preclinical evaluation of endovascular therapeutic devices. The present study is aimed at developing such animal models with a novel approach, emphasizing the role of hemodynamics.
Using 18 carotid arteries from 9 miniswine, surgical partial ligation (approximately...
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... divided into 2 subgroups based on time points of sacrifice: Ia and IIa, 3 months after the surgical procedure; Ib and IIb, 6 months after the surgical procedure. Animals for group III were sacrificed at 6 months. Allocation of experimental animals is summarized in Table 1. All animals were fed with a high-fat, high-cholesterol diet (Test Diet; Purina, St. Louis, Mo) to induce hypercholesterolemia. The diet was started at least 14 days before the surgical procedure and contin- ued for the duration of the study until the time of sacrifice. A blood sample was collected at the time of the surgical procedure after an 18-hour fast to document hyperlipidemia. After the surgical procedure, all animals were placed on aspirin, 81 mg daily, for a month to minimize the risk of thrombotic occlusion that surgical or endovascular procedures could possibly cause. Aspirin has been shown to inhibit platelet aggregation in swine. 16 A low dose (81 mg) of aspirin was chosen because aspirin administration of 100 mg daily was shown to completely inhibit platelet aggregation in swine weighing 55–97 kg. 16 Given that animals used in the present study weighed 20 –30 kg, 81 mg of aspirin was considered sufficient. All animal experiments were conducted in accordance with policies set by the institutional Chancellor’s Animal Research Committee and National Institutes of Health guidelines. Anesthesia was induced with intramuscular tiletamine and zolazepam (Telazol) followed by orotracheal intubation. One percent to 2% isoflurane was given to maintain general anesthesia for the duration of the procedure. A 6F introducer sheath was inserted into the right or left femoral artery for the purpose of an angiogram at the end of the surgery. A midline skin incision was placed at the neck after steriliza- tion of the surgical field. The common carotid arteries were dissected approximately 5 cm in length. A common carotid artery was tied off with 5– 0 Prolene (Ethicon, Cornelia, Ga) along with a spacer (approximately 1.3 mm in diameter) placed on the external surface of the artery (Fig 1 A ). This was subsequently pulled out, leaving a tight stenosis (Fig 1 B ). Postoperative angiography was then carried out to document the degree of surgical stenosis. The surgical wound was closed layer by layer, and the groin site was manually compressed for complete hemostasis. Postoperatively, the animals were maintained under dietary hypercholesterolemia for either 3 (subgroup Ia) or 6 months (subgroup Ib) before being sacrificed in the fashion to be described. Under general anesthesia, the carotid artery was dissected and pre- pared for ligation after the balloon injury procedure. A 6F ...
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... divided into 2 subgroups based on time points of sacrifice: Ia and IIa, 3 months after the surgical procedure; Ib and IIb, 6 months after the surgical procedure. Animals for group III were sacrificed at 6 months. Allocation of experimental animals is summarized in Table 1. All animals were fed with a high-fat, high-cholesterol diet (Test Diet; Purina, St. Louis, Mo) to induce hypercholesterolemia. The diet was started at least 14 days before the surgical procedure and contin- ued for the duration of the study until the time of sacrifice. A blood sample was collected at the time of the surgical procedure after an 18-hour fast to document hyperlipidemia. After the surgical procedure, all animals were placed on aspirin, 81 mg daily, for a month to minimize the risk of thrombotic occlusion that surgical or endovascular procedures could possibly cause. Aspirin has been shown to inhibit platelet aggregation in swine. 16 A low dose (81 mg) of aspirin was chosen because aspirin administration of 100 mg daily was shown to completely inhibit platelet aggregation in swine weighing 55–97 kg. 16 Given that animals used in the present study weighed 20 –30 kg, 81 mg of aspirin was considered sufficient. All animal experiments were conducted in accordance with policies set by the institutional Chancellor’s Animal Research Committee and National Institutes of Health guidelines. Anesthesia was induced with intramuscular tiletamine and zolazepam (Telazol) followed by orotracheal intubation. One percent to 2% isoflurane was given to maintain general anesthesia for the duration of the procedure. A 6F introducer sheath was inserted into the right or left femoral artery for the purpose of an angiogram at the end of the surgery. A midline skin incision was placed at the neck after steriliza- tion of the surgical field. The common carotid arteries were dissected approximately 5 cm in length. A common carotid artery was tied off with 5– 0 Prolene (Ethicon, Cornelia, Ga) along with a spacer (approximately 1.3 mm in diameter) placed on the external surface of the artery (Fig 1 A ). This was subsequently pulled out, leaving a tight stenosis (Fig 1 B ). Postoperative angiography was then carried out to document the degree of surgical stenosis. The surgical wound was closed layer by layer, and the groin site was manually compressed for complete hemostasis. Postoperatively, the animals were maintained under dietary hypercholesterolemia for either 3 (subgroup Ia) or 6 months (subgroup Ib) before being sacrificed in the fashion to be described. Under general anesthesia, the carotid artery was dissected and pre- pared for ligation after the balloon injury procedure. A 6F ...
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... animal surgery was performed successfully. Various degrees of atherosclerotic plaque were successfully induced except 3 arteries for group II, which resulted in subacute thrombotic occlusion. Advanced plaques with intraplaque hemorrhage and/or calcification were commonly seen in group I; however, the most characteristic feature of lesions induced in group II was intimal thickening ( Fig 2). The mean plasma cholesterol level for each group and subgroup is shown in Table 2. No significant intersubgroup or intergroup differences were found. The mean value from all animals was 862 Ϯ 76 mg/dL. These figures are approximately 10 times higher than those observed in swine fed with a regular diet. 18 The mean degree of surgical stenosis at surgery for each group and subgroup is shown in Table 2. There was no intersub- group significant difference except for group III. Final angiograms performed at the time of sacrifice showed that 3 of 9 (30%) arteries in group II (1 of 5 in subgroup IIa and 2 of 4 in subgroup IIb) were occluded, whereas all arteries in group I remained patent. The rate of total occlusion for group II was higher than that for group I, but not significantly so. All arteries in groups I and II demonstrated various degrees of poststenotic dilation (Fig 1 C ). The mean degree of poststenotic dilation of treated arteries is shown in Table 2, where 3 occluded arteries in group II were excluded because poststenotic dilation was not documented as a result of subacute vessel occlusion. No significant differences were found between the mean degree of poststenotic dilation of group I and II at either 3 months (subgroup Ia versus IIa) or 6 months (subgroup Ib versus IIb). Cross-sections stained with hematoxylin-eosin demonstrated various degrees of atherosclerosis in 6 of 6 (100%) and 6 of 9 (67%) arteries for group I and II, respectively. They were more prominent proximal to the surgical stenosis. Three control arteries in group III remained intact although the animals re- ceived a high-fat diet for 6 months. Three of 9 arteries (33%) of group II were occluded by organized thrombus, most proba- bly related to the balloon injury to the arterial intima. All atherosclerotic lesions in group I and II contained intimal fibromuscular proliferation with large collections of foamy macrophages. Histologic features of more advanced atherosclerosis, such as foci of necrosis, calcium deposition, and/or intraplaque hemorrhage were observed in 4 of 6 (66.7%) arteries in group I (3 of 3 in subgroup Ia and 1 of 3 in subgroup Ib). None of specimens from group II (subgroups IIa and IIb) demonstrated these features. The histologic features observed in group I were organized in layers, closely resembling human atherosclerotic plaque (Fig 3). Foamy macrophages were within the bottom of plaque, often with an overlying fibromuscular cap (Fig 3 A , -B ) and foci of necrosis in their central portions (Fig 3 C ). SMA staining showed immunoreactive smooth muscle cells and myofibroblasts immediately beneath the luminal aspect of the plaque (Fig 3 B ). Calcium deposition, most often found deep within plaques, was also clearly visualized (Fig 3 D ). EVG staining exhibited abundant collagen fibers and partially destroyed internal elastic membranes (Fig 3 E ). In 3 of 6 (50.0%) arteries in group I (2 of 3 in subgroup Ia and 1 of 3 in subgroup Ib), even the occurrence of intraplaque hemorrhage correspond- ing to the AHA criteria type 6 (ie, the most advanced [and often symptomatic] stage of atherosclerosis) was found (Fig 3 A ). Such lesions were not found in any specimens from group II. Lesions were eccentric in all (100%) arteries in group I, whereas only 2 of 9 arteries (22%) in group II showed such eccentricity. All these observations suggest that histologic features of atherosclerotic plaques in group I are quite comparable with advanced atherosclerotic lesions encountered in clinical practice. The mean plaque stage scores for each group and subgroup are shown in Table 2 and Fig 4. Intersubgroup differences were significant between Ia versus IIa and Ia versus III. In summary, surgical partial ligation without balloon injury developed significantly more advanced plaques than that with superimposed balloon injury at 3 months. The mean degree of cross-sectional area stenosis (%) is shown in Table 2 and Fig 4. Although the area stenosis for subgroups Ia and Ib seems to be higher than for IIa and IIb, respectively, no statistically significant difference was found. Although the plaque stage score for subgroup Ia was higher than that for subgroup Ib, the difference was not statistically significant. When subgroups (Ia and Ib, IIa, and IIb) are considered to- gether, interaction between time points and subgroups was ruled out, and the mean degree of area stenosis for group I was significantly higher than that for group III. There was no statistically significant difference between groups II versus III. These observations suggest that surgical partial ligation without balloon injury developed significantly more massive plaques than in control swine whereas that with superimposed balloon injury did not. In this series, all arteries for group I (surgical partial ligation without balloon injury) demonstrated various degrees of atherosclerosis in the portion proximal to the surgical stenosis. More importantly, 4 of 6 arteries developed advanced plaque histologically characterized by calcification and/or intraplaque hemorrhage. In contrast, all 6-month sham-oper- ated arteries (group III) remained free of atheroma. The surgical partial ligation model without balloon injury has several advantages over currently used models. First, no mechanical injury is necessary in this model. Maintained intact endothelium allows in vivo evaluation of endothelial function exposed to hemodynamic instability. Healthy endothelium plays a pivotal role in vascular ho- meostasis, not only by mediating vasomotion 19 but also by suppressing thrombosis, 20 vascular inflammation, 21 and proliferation 22 in response to blood flow dynamics. Intensive studies of the in vitro endothelial response to fluid shear stress have been performed using cultured endothelial cells plated within a flow chamber. They demonstrated that ...
Citations
... 2 One study reported that a carotid artery stenosis model using mini pigs induced intimal thickening similar to the atherosclerotic plaque by partially ligating the carotid artery, changing the hemodynamics, and administering a high cholesterol diet. 3 We thus attempted to induce plaque in rat carotid arteries, believing that it would be a highly versatile disease model if we could induce intimal thickening similar to atherosclerotic plaque. On our first attempt, we surgically exposed the carotid artery of rats, ligated it at one point with a 0.3-mm wire, and removed the wire. ...
Objective Plaque induction through intimal injury using a balloon catheter in small animals and by artificial ligation of the carotid artery in large animals have been reported. However, these reports have not yet succeeded in inducing stable plaques nor creating a high degree of intimal thickening to be used as animal models. We have previously developed a plaque induction model in rats but have failed to obtain a plaque incidence frequency that can be used as a model. Thus, in the current study, we aimed to create a versatile disease model to examine the pharmacokinetics of drug administration, determine the efficacy of treatment, and examine the process of intimal thickening. We also attempted to create an improved model with shorter, more frequent, and more severe intimal thickening.
Materials and Methods The common carotid artery of male Wistar rats was surgically exposed and completely ligated with a wire and 6–0 nylon thread. Then, the wire was removed to create a partial ligation. To create a high frequency and high degree of intimal thickening, 72 rats were divided into two groups: a single lesion group with a 0.25-mm wire and a single ligature point, and a tandem lesion group with a 0.3-mm wire and two ligature points. Each group was further divided into normal diet and high cholesterol diet groups. The presence and frequency of intimal thickening were examined for each group after 4, 8, and 16 weeks of growth.
Results In the single lesion group, intimal thickening was observed in 42% of the 4-week group and 75% of the 8-week group. In the tandem lesion group, intimal thickening was observed in 75% of the 4-week group and 50% of the 8-week group. In addition, 50% of the individuals reared for 16 weeks developed intimal thickening.
Conclusion We successfully induced intimal thickening in the carotid arteries of rats with high frequency in the single lesion and tandem lesion groups. The results also showed that the tandem lesion group tended to induce intimal thickening earlier than the single lesion group.
... This indicates that the induction model is suitable for hypercholesterolemia research in experimental animals without causing developmental disorders [21]. A high-fat diet combined with partial carotid artery ligation is able to create a marked atherosclerotic condition in experimental animals [22]. ...
... according to the researchers (Butcher et al., 2011;Simmons et al., 2005). In swine, atherosclerotic plaque progress can be enhanced by combining a high-cholesterol diet with nearby formed vascular injury forced by a variety of methods, such as guide-wire-induced injury (De Smet et al., 1998;Granada et al., 2009), endovascular balloon inflation with or without stent deployment, (Thim et al., 2010), partial vessel ligation, (Ishii et al., 2006) in addition to percutaneous intramural injection of cholesteryl esters and human oxLDL after a 2-week balloon angioplasty (Granada et al., 2005;Granada et al., 2007). In addition to reducing the problems in care and high preservation costs linked with the use of swine models by shortening the study's duration, atherogenic diets and vascular injury protocols are also highly relevant models for translational research in the field of percutaneous interventions and cardiovascular imaging animal models (Fuster et al., 2012). ...
Calcific Aortic Valve Disease (CAVD) is a sluggish and progressive disease that comprises "early sclerosis, characterized by leaflet thickening without left ventricular outflow obstruction, to late stenosis with stiffened leaflets, obstructed flow and compromised cardiac function". CAVD was formerly believed to afflict the tricuspid or congenitally bicuspid aortic valve and be a passive, senile, or degenerative disorder. However, recent investigations have demonstrated that this is a pathobiological activity that is active and heavily cell-mediated, which shares several risk factors with atherosclerosis. Numerous studies show that CAVD are not a normal aspect of aging and may be linked to certain risk factors. Nevertheless, no pharmacological therapy available to halt or arrest the development of CAVD in a clinically relevant way, and surgery is the only effective treatment option. As a result, there is an urgent scientific need to determine pathobiological mechanism of CAVD and to find new ways to treat CAVD. Animal models are developing as crucial instruments to this aim, assisted by the development of new models and greater knowledge of the efficacy of old models. In this review paper, we will present the most extensively utilized large and small animal models that were used to explore CAVD.
... according to the researchers (Butcher et al., 2011;Simmons et al., 2005). In swine, atherosclerotic plaque progress can be enhanced by combining a high-cholesterol diet with nearby formed vascular injury forced by a variety of methods, such as guide-wire-induced injury (De Smet et al., 1998;Granada et al., 2009), endovascular balloon inflation with or without stent deployment, (Thim et al., 2010), partial vessel ligation, (Ishii et al., 2006) in addition to percutaneous intramural injection of cholesteryl esters and human oxLDL after a 2-week balloon angioplasty (Granada et al., 2005;Granada et al., 2007). In addition to reducing the problems in care and high preservation costs linked with the use of swine models by shortening the study's duration, atherogenic diets and vascular injury protocols are also highly relevant models for translational research in the field of percutaneous interventions and cardiovascular imaging animal models (Fuster et al., 2012). ...
Calcific Aortic Valve Disease (CAVD) is a sluggish and progressive disease that comprises "early sclerosis, characterized by leaflet thickening without left ventricular outflow obstruction, to late stenosis with stiffened leaflets, obstructed flow and compromised cardiac function". CAVD was formerly believed to afflict the tricuspid or congenitally bicuspid aortic valve and be a passive, senile, or degenerative disorder. However, recent investigations have demonstrated that this is a pathobiological activity that is active and heavily cell-mediated, which shares several risk factors with atherosclerosis. Numerous studies show that CAVD are not a normal aspect of aging and may be linked to certain risk factors. Nevertheless, no pharmacological therapy available to halt or arrest the development of CAVD in a clinically relevant way, and surgery is the only effective treatment option. As a result, there is an urgent scientific need to determine pathobiological mechanism of CAVD and to find new ways to treat CAVD. Animal models are developing as crucial instruments to this aim, assisted by the development of new models and greater knowledge of the efficacy of old models. In this review paper, we will present the most extensively utilized large and small animal models that were used to explore CAVD.
... The establishment of a suitable animal model of carotid artery stenosis is essential for the research of the occurrence and development of common carotid artery stenosis and the subsequent hemodynamic changes caused by it, which is beneficial for studying the development and mechanism changes of human common carotid atherosclerosis. Since the anatomy of the circulatory system of rabbits is similar to that of humans, this kind of experiment can better simulate the actual situation of humans (Ishii et al., 2006). In this study, 12 rabbit common carotid artery balloon stenosis models were successfully made by establishing fluoroscopy-guided common carotid artery balloon injury models. ...
Background: The objective of this study is to establish a minimally invasive technique to create a stable carotid artery stenosis rabbit model. This article summarizes the specific methods and key points of this technology.
Methods: The experiment studied a rabbit that was anesthetized through the vein. After the femoral artery was exposed, a minimally invasive needle was used to puncture the femoral artery, then the sheath was placed into the artery. We primarily put a catheter in the ascending aorta for angiography and then used a PT2 guidewire for super-selection. The PT2 guidewire was retained, and a balloon was placed in the right common carotid artery (CCA) through a guidewire to inflate it three times. Six rabbits in the 2- (2W) and 4-week (4W) groups were examined at 14 and 28 days, respectively. The rabbits in the control group received angiography at the beginning and 28 days later but without balloon injury. After angiography assessment, specimens of right CCA were dissected. Pathological and immunohistochemical examinations were performed on the collected specimens, and iFlow analysis was performed as well.
Results: All the 18 animals which survived were observed. The rabbits in the 2W and 4W groups showed stenosis of the right CCA. Digital subtraction angiography showed the diameter was lower than that in the control group (1.04 ± 0.1, 0.71 ± 0.12, and 1.83 ± 0.08 mm in 2W, 4W, and control group, P < 0.05). Pathology also suggested carotid stenosis and obvious intimal hyperplasia. The results of immunohistochemistry showed that α-smooth muscle actin was highly expressed in the 2W and 4W groups, and the integrated optical density (IOD) value was higher than that in the control group (14,807.11 ± 1,822.3, 22,245.96 ± 1,212.82, and 6,537.16 ± 1,186.62 in the 2W, 4W, and control group, P < 0.05). Meanwhile, a cluster of differentiation 31 (CD31) was low expressed in the 2W and 4W groups, and the IOD value was lower than that in the control group (519.14 ± 44.4, 1,029.64 ± 98.48, and 1,502.05 ± 88.79 in the 2W, 4W, and control group, P < 0.05), which suggested endothelial damage and partial repair. The analysis by iFlow showed that the time-to-peak after balloon strain in the 2W and 4W groups were longer than that in the control group.
Conclusion: We established a minimally invasive, effective, and safe method to establish a carotid artery stenosis rabbit model. The highlights of this technology were the application of minimally invasive methods, reducing surgical bleeding, infection, and related complications. This technology avoided the influence of tissue around CCA in the traditional carotid artery balloon injury model, which might lead to more accurate treatment outcomes.
... Consequently, most recent studies tend to use in vivo testing for non-human animals in experiments that seek to control the variables that affect the actions or biological system under study. [14][15][16][17][18][19][20][21] The use of the mini-swine as a nonrodent species in research has continued to expand for over a decade, and they are becoming routinely used both in experimental pharmacology and as a therapeutic model for human diseases. 21 Chinese mini-swines, which has the most similar blood and vessel characteristics comparing to human beings, has been widely used in experimental hemodynamics study. ...
An experiment-based computational study that helps analyze blood flow behavior and wall shear stress (WSS) distribution is reported in this work. Large scale numerical analysis of hemodynamics in swine-specific stenosed carotid artery based on in vivo surgery is presented. A pressure stabilized domain decomposition method is used to symmetrize the linear systems of Navier-Stokes equations and the convection-diffusion equation. A numerical expression of swine blood flow and a detailed swine carotid vessel model with stenosis are newly proposed, and the empirical function of WSS was validated for the swine model. Two wall models, a rigid and another elastic, are compared in precisely modelling for pathological analysis of vascular disease like carotid atherosclerosis and hemangioma. The flexible wall performs better in representing experimental conditions while the stern wall is much more efficient. Numerical results show that the stenosis has a great influence on the behavior and characters of blood and its subsequent affect the WSS of the vessel; further details show how stenosis affect the distribution and magnitude of wall shear stress in an artery which lay a foundation for further medical study.
... Common forms of cerebrovascular disease include carotid artery atherosclerosis, and intracranial aneurysms (ICA). Similar to other regions of the body, onset and prognosis of cerebrovascular diseases is dependent on local flow properties, vascular biomechanics, and tissue remodeling [20,[73][74][75][76], creating a need for animal models and CFD analysis. CFD enables quantification of local flow properties including WSS and OSI, while small animal models allow observations on vascular remodeling [77]. ...
... Carotid artery atherosclerosis is characterized by the buildup of plaque within the arterial wall, causing stenosis. Carotid artery atherosclerosis and ICAs can be induced by systemic or local methods [78], or some combination of the two [75,79]. Systemic methods most often incorporate genetic knockout or modification, hyperlipidemia, hyperglycemia, or hypertension. ...
Recent applications of Computational Fluid Dynamics (CFD) applied to the cardiovascular system have demonstrated its power in investigating the impact of hemodynamics on disease initiation, progression, and treatment outcomes. Flow metrics such as pressure distributions, wall shear stresses, and blood velocity profiles can be quantified to provide insight into observed pathologies, assist with surgical planning, or even predict disease progression. While numerous studies have performed simulations on clinical human patient data, it often lacks pre-diagnosis information and can be subject to large inter-subject variability, limiting the generalizability of findings. Thus, animal models are often used to identify and manipulate specific factors contributing to vascular disease because they provide a more controlled environment. In this review, we explore the use of CFD in animal models in recent studies to investigate the initiating mechanisms, progression, and intervention effects of various vascular diseases. The first section provides a brief overview of the CFD theory and tools that are commonly used to study blood flow. The following sections are separated by anatomical region, with the abdominal, thoracic, and cerebral areas specifically highlighted. We discuss the associated benefits and obstacles to performing CFD modeling in each location. Lastly, we highlight animal CFD studies focusing on common surgical treatments, including arteriovenous fistulas and pulmonary artery grafts. The studies included in this review demonstrate the value of combining CFD with animal imaging and should encourage further research to optimize and expand upon these techniques for the study of vascular disease.
... Atherosclerotic plaque models with larger diameter vessels will be required for future applications in a human internal carotid artery or common carotid artery. Our system will need to be evaluated by more subjects including other animal plaque models with larger vessels close to humans, such as a swine model [44], before clinical trials. Furthermore, gender-associated differences in human atherosclerotic plaques are important especially for our future clinical application of the system as several human studies showed the differences [45]. ...
Background and aims:
Detecting detailed atherosclerotic plaques is important to reduce risk factors during surgery. However, there are few methods to evaluate them during surgery. The aim of this study was to establish an in vivo, non-contact, and label-free imaging method for identifying atherosclerotic plaque lesions from outside vessels with a diffuse-reflectance near-infrared (NIR) hyperspectral imaging (HSI) system.
Methods:
NIR spectra between 1000 and 2350 nm were measured using an NIR HSI imaging system outside the exposed abdominal aorta in five Watanabe Heritable Hyperlipidemic (WHHL) rabbits in vivo. Preprocessed data were input to a supervised machine learning algorithm called a support vector machine (SVM) to create pixel-based images that can predict atherosclerotic plaques within a vessel. The images were compared with histological findings.
Results:
Absorbance was significantly higher in plaques than in normal arteries at 1000-1380, 1580-1810, and 1880-2320 nm. Overall predictive performance showed a sensitivity of 0.814 ± 0.017, a specificity of 0.836 ± 0.020, and an accuracy of 0.827 ± 0.008. The area under the receiver operating characteristic curve was 0.905 (95% confidence interval = 0.904-0.906).
Conclusions:
The NIR HSI system combined with a machine learning algorithm enabled accurate detection of atherosclerotic plaques within an internal vessel with high spatial resolution from outside the vessel. The findings indicate that the NIR HSI system can provide non-contact, label-free, and precise localization of atherosclerotic plaques during vascular surgery.
... A full spectrum of procedures in a fully functioning arterial tree can be performed, and realistic endovascular access using a percutaneous or surgical cut-down technique is feasible. Even the lack of natural pathology has also been overcome with artificial induction of both occlusive and aneurysmal disease through iatrogenically injuring vessel endothelium [20] and suturing constricting prosthetic patches around surgically exposed vessels [21]. The Porcine Transfer Study [22] showed significantly improved performance parameters in novices undertaking an iliac stenting procedure after training on a porcine model. ...
Endovascular trainees in the National Health Service still largely rely on the apprentice-apprenticeship model from the late 19th century. As the scope for endovascular therapy increases, due to the rapid innovation, evolution and refinement of technology, so too do patients’ therapeutic options. This climate has also opened the door for more novel training adjuncts, to address the gaps that exist in our current endovascular training curriculum. The aim of this paper is to present a succinct overview of endovascular simulation, synthesizing the trials and research behind this rapidly evolving training as well as highlighting areas where further research is required. The authors searched MEDLINE and EMBASE for relevant manuscripts on all aspects of endovascular simulation training. A comprehensive Google search was also undertaken to look for any relevant information on endovascular training courses available and any unpublished work that had been presented at relevant scientific meetings. Papers were categorized into the four models: synthetic, animal, virtual reality and human cadaver, and separate searches for evidence of skill transfer were also undertaken. Authors of novel research projects were contacted for further details of unpublished work and permission granted to report such findings in this manuscript.
... Multiple studies (76)(77)(78) showed the effectiveness of partial carotid ligation in combination with a high-fat diet. Large plaques 7 Van der Heiden, Hoogendoorn, et al. ...
... Large plaques 7 Van der Heiden, Hoogendoorn, et al. Biomechanical assessment of plaque rupture animal models with vulnerable characteristics like a necrotic core, calcium, IPH and thin fibrous cap were seen proximal to the stenosis in the carotid arteries (76,77). Strikingly, adding diabetes as an additional risk factor, did not result in more vulnerable plaques (79).The only pig model that did show frequent signs of rupture in the form of cap rupture and luminal thrombus formation was developed by Jiang et al. (78). ...
Rupture of atherosclerotic plaques is the main cause of acute cardiovascular events. Animal models of plaque rupture are rare but essential for testing new imaging modalities to enable diagnosis of the patient at risk. Moreover, they enable the design of new treatment strategies to prevent plaque rupture. Several animal models for the study of atherosclerosis are available. Plaque rupture in these models only occurs following severe surgical or pharmaceutical intervention. In the process of plaque rupture, composition, biology and mechanics each play a role, but the latter has been disregarded in many animal studies. The biomechanical environment for atherosclerotic plaques is comprised of two parts, the pressure-induced stress distribution, mainly - but not exclusively - influenced by plaque composition, and the strength distribution throughout the plaque, largely determined by the inflammatory state. This environment differs considerably between humans and most animals, resulting in suboptimal conditions for plaque rupture. In this review we describe the role of the biomechanical environment in plaque rupture and assess this environment in animal models that present with plaque rupture.
