Change In Thickness Of Arterial Wall Research Articles

49. Giant cell arteritis and Takayasu arteritis: two sides of the same coin in an elderly female?

49. Giant cell arteritis and Takayasu arteritis: two sides of the same coin in an elderly female?

Vessel wall and lumen characteristics with age in healthy participants using 3T intracranial vessel wall magnetic resonance imaging.

Intracranial vessel wall imaging (VWI) at a clinical field strength of 3T has become more widely available. However, how vessel measurements change with age and sex, over an age range spanning a typical lifespan, are needed. To assess for identifiable changes in arterial wall thickness, outer vessel wall diameter, and lumen diameter with age cross-sectionally in healthy controls without cerebrovascular disease risk factors at the spatial resolution afforded by currently recommended 3T VWI approaches. Prospective. Healthy subjects (n = 82; age = 8-79 years). 3T intracranial VWI, angiography, and T1 -weighted anatomical imaging. Two readers measured lumen and outer wall diameters of the supraclinoid internal carotid artery (ICA) and distal basilar artery. Wall thickness and intraclass correlation coefficients (ICCs) were calculated. Separate linear regressions were performed to understand the relationship between wall measurements (lumen diameter, outer vessel wall diameter, and wall thickness) and age, gender, side (left or right); significance: two-sided P < 0.05. Readers showed excellent agreement for lumen and outer wall diameters (ICC 0.83-094). Linear regression of supraclinoid ICA wall measurements showed a statistically significant increase in wall thickness (P = 0.00051) and outer vessel wall diameter (P = 0.030) with age. ICA lumen and outer vessel wall diameters were statistically greater in males vs. females (lumen diameter 3.69 ± 0.41 vs. 3.54 ± 0.35 mm, P = 0.026; outer wall diameter 5.78 ± 0.52 vs. 5.56 ± 0.44 mm, P = 0.0089) with a trend toward increase in wall thickness (1.05 ± 0.12 vs. 1.01 ± 0.10 mm, P = 0.055). No significant difference was found in basilar artery wall thickness (P = 0.45, P = 0.72), lumen diameter (P = 0.15, P = 0.42), or outer vessel wall diameter (P = 0.34, P = 0.41) with age or gender, respectively. Intracranial vessel wall measurements were shown to be consistent between readers. At the available spatial resolution of 3T intracranial VWI sequences, supraclinoid ICA vessel wall thickness and outer vessel wall diameter appear to mildly increase with age. There was no detectable change in basilar artery vessel wall characteristics with age. 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019;50:1452-1460.

Development Of An Atherothrombotic Occlusion In The Rabbit Carotid Artery: Accessed By New Computerized B- Mode Ultrasound Image Processing Technology And Histopathology

Introduction: Thrombus formation on a disrupted atherosclerotic soft plaque is a key event that leads to atherothrombosis. Atherothrombosis is one of the leading causes of acute coronary syndrome and ischemic stroke. Our ability to test new protocols for the treatment of atherothrombotic stenosis in humans is limited for obvious ethical reasons; therefore, a precise understanding of the mechanism of atherothrombotic occlusion in human carotid artery, which give rise to thrombosis, emboli and stroke, requires a suitable animal model that would mimic the same characteristics well.Aims: The aim of this study was to generate an easily reproducible and inexpensive experimental rabbit carotid model of atherothrombotic occlusion with morphological similarities to the human disease and the subsequent assessment of the reliability of new computerized B- mode ultrasound image processing technology in the study of lumen area stenosis in this model.Methods: Briefly, male New Zealand white rabbits were submitted to common carotid artery atherothrombotic occlusion by primary balloon injury followed 1.5% cholesterol- rich diet injury for eight weeks and finally perivascularly severe cold injury. All of the rabbits' arteries were imaged by B-mode ultrasound weekly, after which the rabbits were sacrificed, and their vessels were processed for histopathology. Ultrasound longitudinal view images from three cardiac cycles were processed by a new computerized analyzing method based on dynamic programming and maximum gradient algorithm for measurement of instantaneous changes in arterial wall thickness and lumen diameter in sequential ultrasound images.Results: Histopathology results showed progressive changes, from the lipid-laden cells and fibrous connective tissue proliferation, fibrolipid plaque formation, resulting in vessel wall thickening, remodeling, neovascularization and lumen narrowing (before perivascularly severe cold injury using liquid nitrogen) up to atherothrombotic occlusion (after perivascularly severe cold injury using liquid nitrogen) in the treatment group respect to other groups (P &lt; 0.05).Conclusion: In conclusion we successfully developed a new rabbit carotid artery model of atherothrombotic occlusion, which is not only quickly and easily reproducible and inexpensive, but also without mortality and similar to the condition seen in patients. The merits of our model render the evaluation of carotid artery atherothrombotic stenosis and its treatment strategies more feasible in humans. This condition in rabbits can be properly assessed by our new computerized B-mode ultrasound image processing technology.

Prediction of Atherosclerotic Plaque Development in an In Vivo Coronary Arterial Segment Based on a Multilevel Modeling Approach.

The aim of this study is to explore major mechanisms of atherosclerotic plaque growth, presenting a proof-of-concept numerical model. To this aim, a human reconstructed left circumflex coronary artery is utilized for a multilevel modeling approach. More specifically, the first level consists of the modeling of blood flow and endothelial shear stress (ESS) computation. The second level includes the modeling of low-density lipoprotein (LDL) and high-density lipoprotein and monocytes transport through the endothelial membrane to vessel wall. The third level comprises of the modeling of LDL oxidation, macrophages differentiation, and foam cells formation. All modeling levels integrate experimental findings to describe the major mechanisms that occur in the arterial physiology. In order to validate the proposed approach, we utilize a patient specific scenario by comparing the baseline computational results with the changes in arterial wall thickness, lumen diameter, and plaque components using follow-up data. The results of this model show that ESS and LDL concentration have a good correlation with the changes in plaque area [R2 = 0.365 (P = 0.029, adjusted R2 = 0.307) and R2 = 0.368 (P = 0.015, adjusted R2 = 0.342), respectively], whereas the introduction of the variables of oxidized LDL, macrophages, and foam cells as independent predictors improves the accuracy in predicting regions potential for atherosclerotic plaque development [R2 = 0.847 (P = 0.009, adjusted R2 = 0.738)]. Advanced computational models can be used to increase the accuracy to predict regions which are prone to plaque development. Atherosclerosis is one of leading causes of death worldwide. For this purpose computational models have to be implemented to predict disease progression.

Ultrasonographic Analysis Versus Histopathologic Evaluation of Carotid Advanced Atherosclerotic Stenosis in an Experimental Rabbit Model

Advanced carotid atherosclerosis with severe stenosis (>70%) is a major clinical risk factor for ischemic stroke. Our ability to test new protocols for the treatment of atherosclerotic stenosis in humans is limited for obvious ethical reasons; therefore, a suitable animal model is required. The aim of this study was to generate an easily reproducible and inexpensive experimental rabbit carotid model of advanced atherosclerosis with morphological similarities to the human disease and the subsequent assessment of the reliability of B-mode ultrasound technology in the study of lumen area stenosis in this model. Briefly, New Zealand white rabbits underwent primary perivascular cold injury at the right common carotid artery followed by a 1.5% cholesterol-rich diet injury for eight weeks. All of the rabbits’ arteries were imaged by B-mode ultrasound weekly, after which the rabbits were sacrificed, and their vessels were processed for histopathology. Ultrasound longitudinal view images from three cardiac cycles were processed by a new computerized analyzing method based on dynamic programming and maximum gradient algorithm for measurement of instantaneous changes in arterial wall thickness and lumen diameter in sequential ultrasound images. Histopathology results showed progressive changes, from the lipid-laden cells and fibrous connective tissue proliferation in neointimal layer, up to the fibro-lipid plaque formation, resulting in vessel wall thickening, remodeling and lumen stenosis. The B-mode ultrasound images and the histologic measurements showed an increase in the mean wall thickness and the lumen area stenosis within eight weeks. Quantitative and morphometric analysis of the mean wall thickness and the lumen area stenosis percentage showed a significant correlation between the B-mode ultrasound and the histological measurements at each time point (R = 0.989 and R = 0.995, p < 0.05, respectively). In conclusion, we successfully produced advanced atherosclerosis in the rabbit carotid artery that is similar to the condition seen in patients. This condition in rabbits can be properly assessed by B-mode ultrasound image processing.

Detection of subclinical coronary atherosclerosis using two-dimensional, high-resolution transthoracic echocardiography

OBJECTIVESWe evaluated whether two-dimensional high-resolution transthoracic echocardiography (HR-2DTTE) can detect changes in arterial wall thickness and size associated with subclinical coronary artery disease (CAD).BACKGROUNDArterial wall thickening, compensatory arterial enlargement and a preserved arterial lumen characterize subclinical atherosclerosis. Detection of these changes during the asymptomatic stage of CAD may allow early treatment and prevention of acute coronary events.METHODSTwenty-six patients with angiographically proven CAD and 29 normal volunteers underwent HR-2DTTE evaluation of the left anterior descending coronary artery (LAD) using an ATL 5000 echograph (Advanced Technology Laboratories, Bothell, Washington) with a 4 to 7 MHz transducer. Significant (>70%) LAD stenosis was present in 15 patients (mean 82%); 11 patients did not have significant LAD stenosis (mean 26%) and represented a surrogate for subclinical LAD disease. Wall thickness, maximal luminal diameter and external diameter of the LAD were measured.RESULTSLeft anterior descending coronary artery wall thickness was larger in patients (1.9 ± 0.4 mm) than it was in volunteers (0.9 ± 0.1 mm, p < 0.001). The external diameter of the LAD was (6.0 ± 1.1 mm) in patients and (3.9 ± 0.7 mm) in volunteers (p < 0.001). Luminal diameter was 2.2 ± 0.5 mm in patients and 2.1 ± 0.6 mm in volunteers (p = NS). There was no difference in wall thickness (1.9 ± 0.4 mm vs. 2.0 ± 0.4 mm), luminal diameter (2.2 ± 0.5 mm vs. 2.2 ± 0.4 mm) and external diameter (5.9 ± 1.0 mm vs. 6.2 ± 1.2 mm) between the patients with <70% and >70% LAD stenosis.CONCLUSIONSLeft anterior descending coronary artery wall thickness and external diameter are significantly increased in patients with CAD as compared with normal subjects, and HR-2DTTE is sensitive enough to detect these differences. Wall thickness and external diameter are increased to the same extent in patients with obstructive and subclinical LAD disease.

High resolution miniature trans-esophageal echocardiography is useful to evaluate atherosclerosis and the effects of alacepril in hyper-cholesterol rabbits.

This study tested the efficacy of high resolution miniature transesophageal echocardiography (m-TEE; 3.5 mm-diameter probe, 7.5 MHz, axial resolution of 0.25 mm) in the evaluation of atherosclerotic lesions of the thoracic aorta rabbits exposed to a high cholesterol diet. The effects of the ACE inhibitor Alacepril (90 mg/kg) on atherosclerosis were also assessed in normotensive, high cholesterol-diet rabbits by m-TEE, both in situ and in vitro. Oral treatment with Alacepril was begun on confirmation of atherosclerosis after a three month high cholesterol diet (group AL). Ultrasound examination reliably distinguished the lesions of atherosclerosis in situ. A three month course of Alacepril treatment decreased the systolic and diastolic blood pressures by approximately 20 and 5 mmHg, produced a regression of atherosclerosis and significantly decreased the intimal plus medial thickness compared with hyperlipidemic-controls (group HC) (1.0 + 0.3 vs 1.6 + 0.4 mm, p < 0.02). The intimal surface involvement area in group AL was marginally smaller than in group HC (57 + 23 vs 76 + 23%, p = 0.06). The high dose of Alacepril in this study did not affect the serum levels of t-cholesterol, HDL-C, LDL-C, triglycerides, or apoproteins A-I and B. These results suggest that Alacepril can produce regression of atherosclerosis, without changing circulating lipoprotein or apoprotein levels. Further miniature TEE offers high repeatability and is useful both in situ and in vitro for determining changes in arterial wall thickness and the severity of atherosclerosis.