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81.
82.
目的:探讨颈动脉狭窄≤50%的颈动脉斑块患者的MRI斑块特征及临床因素与发生缺血性脑卒中的关系。方法:选取2014年9月—2016年2月超声筛选颈动脉狭窄≤50%的颈动脉斑块患者43例,所有患者行核磁共振黑血成像检查,分析MRI斑块特征及其他危险因素与缺血性脑卒中的关系。结果:43例患者的颈动脉斑块狭窄程度5%~50%,随访时间1.9~19.4个月。随访期间发现脑梗死患者共4例。单因素与多因素Logistic回归分析结果显示,仅MRI的斑块内出血与缺血性脑卒中的发生有明显关系(OR=297.797,95%CI=2.638~33620,P=0.018),而其他斑块特征及临床因素均无明显关系(均P0.05)。Kaplan-Meier生存分析显示,有斑块内出血者较无斑块内出血者的中位无脑卒中时间明显缩短(14.3个月vs. 18.6个月,P=0.001);有冠心病者较无冠心病者的中位无脑卒中时间也明显缩短(12.1个月vs. 18.7个月,P=0.029);Cox回归分析显示,斑块内出血(HR=18.2,95%CI=2.7~123.3,P=0.003)及冠心病(HR=27.4,95%CI=1.6~464.3,P=0.022)是缺血性脑卒中发生的独立危险因素。结论:在颈动脉狭窄≤50%的颈动脉斑块患者中,斑块内出血与冠心病是缺血性卒中的发生密切相关。 相似文献
83.
Buchanan DN Lindenmaier T McKay S Bureau Y Hackam DG Fenster A Parraga G 《Ultrasound in medicine & biology》2012,38(7):1145-1153
The relationship of three-dimensional ultrasound (3DUS)-derived carotid vessel wall volume (VWV) was evaluated with respect to age and sex. B-mode and 3DUS images were acquired for 316 subjects from diverse groups including obese primary prevention, diabetic nephropathy, renal transplant and rheumatoid arthritis populations. The relationship for intima-media thickness (IMT) and VWV with age and sex were determined using Pearson-product-moment correlations. Mean IMT (r = 0.18, p = 0.001) and VWV (r = 0.24, p < 0.01) correlated modestly with age. There were modest correlations in males (IMT, r = 0.19, p = 0.003; VWV, r = 0.34, p < 0.001) and in females for IMT and age (r = 0.30, p = 0.007) but not between 3DUS VWV and age in females (r = 0.10, p = 0.4). Significant associations between plaque and VWV (r = 0.36, p = 0.001) but not IMT suggest different correlations in females that may be attributed to plaque. 相似文献
84.
Allison L. Kuipers Candace M. Kammerer Iva Miljkovic Genevieve A. Woodard Clareann H. Bunker Alan L. Patrick Victor W. Wheeler Anne B. Newman Joseph M. Zmuda 《Atherosclerosis》2013
Objective
Intima-media thickness, adventitial diameter and lumen diameter are indicators of cardiovascular disease risk. The influence of genetic factors on these measures in African ancestry populations is not well defined. Therefore, we estimated heritability and performed genome-wide linkage analysis of carotid ultrasound traits in 7 multigenerational families of African ancestry.Methods
A total of 395 individuals (7 pedigrees; mean family size = 56; 2392 relative pairs) aged ≥18 years had a common carotid artery ultrasound scan. Statistical analyses were conducted using pedigree-based maximum likelihood methods.Results
Significant covariates included age, sex, body mass index or height and waist, and systolic blood pressure. Residual heritabilities ranged from 0.35 ± 0.10 to 0.64 ± 0.12 (P < 0.0001). We identified a novel quantitative trait locus for adventitial and lumen diameters on chromosome 11 (max LOD = 4.09, 133 cm).Conclusion
Further fine mapping of this region may identify specific mutations predisposing to subclinical vascular disease among African ancestry individuals. 相似文献85.
P. Shen Y. Zhou A. Song Y. Wan Z. Fan R. Xu 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(8):2376-2381
Background and aimsWe aimed to evaluate the association between different obese phenotypes with carotid artery plaque (CAP) event.Method and resultsThe current retrospective cohort study was performed in 32,778 Chinese adults (19,221 men and 13,557 women, aged 41.9 ± 11.0 years). Obese phenotypes were assessed based on baseline body mass index (<24.0 vs. ≥24.0 kg/m2) and metabolic characteristics (health vs. unhealth). All the participants were further classified into four groups: metabolic health and normal weight (MHNW), metabolic unhealth and normal weight (MUHNW), metabolic health and overweight (MHO), and metabolic unhealth and overweight (MUHO). Ultrasound B-mode imaging was annually performed to evaluate CAP throughout the study. We have identified 2142 CAP cases during 5-year follow-up. Comparing with the MHNW group, the hazard ratios for the risk of incident CAP was 2.44 (95% CI:1.92 and 3.09) for the MUHNW group, 1.52 (95% CI:1.06 and 2.18) for the MHO group, and 1.8 (95% CI:1.4 and 2.33) for the MUHO group. The association was more pronounced in young adults (<65 y) than that in aged adults (≥65 y). Sensitivity analysis generated similar results with the main analysis.ConclusionMUHNW, MHO, and MUHO were associated with the risk of CAP. 相似文献
86.
Carotid intima-media thickness is increased in subjects with ischemic heart disease having a familial incidence 下载免费PDF全文
Chiharu Kishimoto Miki Hirata Kaori Hama Masami Tanaka Kazushi Nishimura Shigeru Kubo Kinzo Ueda Tatsuo Fujioka Shunichi Tamakil 《Experimental & Clinical Cardiology》2006,11(1):8-10
OBJECTIVES: A family history of ischemic heart disease (IHD) is an independent risk factor for cardiovascular events. However, the mechanisms underlying this susceptibility have not been fully elucidated. The authors hypothesized that an important mediator of the familial incidence of IHD is subclinical atherosclerosis, which is detectable by noninvasive imaging. METHODS: One hundred forty-seven consecutive subjects (mean age 61.9 years, 57% men) were studied for one year using carotid ultra-sonogrophy for general medical screening, and familial IHD events were validated. Using a 7.5 MHz linear array transducer, carotid intima-media thickness (IMT) and carotid plaque were assessed. Subjects were subsequently divided into four groups based on the severity of IMT. RESULTS: The familial incidence of IHD and incidence of plaque were associated with the severity of IMT. No significant differences in risk factors were found between subjects with and without a family history of IHD. CONCLUSIONS: These findings suggest that subclinical atherosclerosis, as assessed in the carotid arteries, is more prevalent in individuals with a family history of IHD. 相似文献
87.
李立 《临床超声医学杂志》2006,8(5):270-272
目的探讨2型糖尿病与颈动脉粥样硬化的关系及高频超声检测糖尿病患者颈动脉的意义。方法对临床确诊的2型糖尿病患者58例及正常对照组人群60例行高频超声检测。测量颈动脉内膜-中膜(IMT)厚度,观察管壁有无斑块、斑块性质、分类血流动力学变化。结果糖尿病组颈动脉IMT增厚与斑块形成的发生率与对照组比较差异有显著意义。糖尿病合并脑卒中的患者中,颈动脉IMT增厚的发生率为100%,粥样硬化斑块的发生率达到92.3%。结论糖尿病是颈动脉粥样硬化的易患因素,高频超声能清晰显示糖尿病患者的颈动脉病变情况,为临床诊断和治疗提供重要依据。 相似文献
88.
目的:探讨藏族人群高血糖症与颈动脉粥样硬化的关系。方法:以拉萨市藏族人群为研究对象,进行临床调查、生化检查和颈动脉检查。检查并分析449例藏族人的糖耐量,糖基化血红蛋白、血压、血脂、空腹胰岛素含量和颈总动脉内中膜厚度。结果:根据糖耐量试验的结果,将研究对象分为3组:正常糖耐量组(NGT)352例,糖耐量低减组(IGT)62例,糖尿病组(DM)35例。患者糖耐量异常的程度越高,患者年龄越大(P<0.01),高血压发病率越高(P<0.05),胰岛素抵抗指数(HOMA-IR)越大(P<0.001),糖基化血红蛋白值越高(P<0.01),血糖(P<0.001)、甘油三酯浓度(P<0.05)越高,高密度脂蛋白-胆固醇水平越低(P<0.05)。IGT和DM组的颈动脉粥样硬化程度远比NGT组严重(P<0.001)。多元回归分析表明,增龄、胆固醇、甘油三酯、低密度脂蛋白、糖基化血红蛋白和胰岛素抵抗指数的自然对数ln(HOMA-IR)是颈动脉粥样硬化的独立危险因素(P<0.05)。结论:高糖血症的藏族人群动脉粥样硬化程度严重。糖基化血红蛋白、增龄、血脂异常、胰岛素抵抗是颈动脉粥样硬化的重要因素。 相似文献
89.
目的:观察老年单纯收缩期高血压(EISH)患者降压治疗前、后颈动脉粥样硬化的改变。方法:以彩色多普勒超声仪检查109例EISH患者降压治疗前、后颈动脉的形态、结构和血流动力学等指标,并进行分析。结果:降压治疗使斑块性质改变(P<0.01),阻力指数(RI)降低、搏动指数(PI)降低(P<0.01)。结论:EISH患者在良好控制血压后,可改善颈动脉硬化程度。 相似文献
90.
Marcela Hernández Hoyos Piotr Orłowski Ewa Piątkowska-Janko Piotr Bogorodzki Maciej Orkisz 《International journal of computer assisted radiology and surgery》2006,1(1):51-61
The accuracy of 2D phase contrast (PC) magnetic resonance angiography (MRA) depends on the alignment between the vessels and
the imaging plane. PC MRA imaging of blood flow is challenging when the flow in several vessels is to be evaluated with one
acquisition. For this purpose, semi-automatic determination of the plane most perpendicular to several vessels is proposed
based on centerlines extracted from 3D MRA. Arterial centerlines are extracted from 3D MRA based on iterative estimation-prediction,
multi-scale analysis of image moments, and a second-order shape model. The optimal plane is determined by minimizing misalignment
between its normal vector and the centerlines’ tangent vectors. The method was evaluated on a phantom and on 35 patients,
by seeking the optimal plane for cerebral blood flow quantification simultaneously in internal carotids and vertebral arteries.
In the phantom, difference of orientation and of height between known and calculated planes was 1.2° and 2.5 mm, respectively.
In the patients, all but one centerline were correctly extracted and the misalignment of the plane was within 12° per artery.
Semi-automatic centerline extraction simplifies and automates determination of the plane orthogonal to one vessel, thereby
permitting automatic simultaneous minimization of the misalignment with several vessels in PC MRA. 相似文献