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61.
目的:探讨原发性高血压患者颈动脉粥样硬化程度与中医辨证分型的关系。方法:用高频(11.4 MHz)彩色多普勒超声检测了130例原发性高血压及心脑血管并发症患者的颈动脉,与37例非高血压心脑血管病患者作对照。结果:高血压各组颈动脉内中膜厚度及斑块检出率均高于对照组,以合并脑血管疾病组内中膜厚度高于单纯高血压组。高血压中医证型之间比较,以痰湿壅盛型内中膜厚度明显高于其他证型,斑块检出率以阴虚阳亢和痰湿壅盛型明显高于其他证型。结论:高血压是引起颈动脉内中膜厚度增加的重要因素。颈动脉粥样硬化程度可作为预测心脑血管病存在的参考指标。动脉硬化的病因病机与痰、瘀密切相关。  相似文献   
62.
Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.  相似文献   
63.
BackgroundThe ability of coronary CT angiography (CTA) findings such as plaque characteristics to predict future coronary events remains controversial.ObjectiveWe investigated whether noncalcified atherosclerotic lesions (NCALs) detected by coronary CTA were predictive of future coronary events.MethodsA total of 511 patients who underwent coronary CTA were followed for cardiovascular events over a period of 3.3 ± 1.2 years. The primary end point was defined as hard events, including cardiac death, nonfatal myocardial infarction, or unstable angina that required urgent hospitalization. Early elective coronary revascularizations (n = 58) were excluded. The relationship between features of NCALs and outcomes is described.ResultsA total of 15 hard events (2 cardiac deaths, 7 myocardial infarctions, 6 cases of unstable angina that required urgent hospitalization) were documented in the remaining 453 patients with modest risks during a follow-up period of 3.3 ± 1.2 years. For these hard events, a univariate Cox proportional hazard model showed that the hazard ratio for the presence of >50% stenosis was 7.27 (95% CI, 2.62–21.7; P = .0002). Although the presence of NCAL by itself was not statistically significant, NCALs with low attenuation and positive remodeling (low-attenuation plaque [LAP] and positive remodeling [PR]; plaque CT number ≤34 HU and remodeling index ≥1.20) showed an adjusted hazard ratio of 11.2 (95% CI, 3.71–36.7; P < .0001). With C-statistics analysis, when both LAP and PR and >50% stenosis were added, the C-statistic was significantly improved compared with the basal model adjusted for age, sex, and log2 (Agatston score +1) (0.900 vs 0.704; P = .0018).ConclusionsIdentification of NCALs with LAP and PR characteristics by coronary CTA provides additional prognostic information to coronary stenosis for the prediction of future coronary events.  相似文献   
64.
目的:探讨阿司匹林联合氯吡格雷治疗伴易损斑块的症状性颈动脉狭窄患者的疗效和安全性。方法利用颈动脉超声检查筛选205例存在颈动脉易损斑块,且颈动脉狭窄<50%的缺血性卒中患者,随机分为阿司匹林治疗组(单抗组)102例和阿司匹林联合氯吡格雷治疗组(双抗组)103例,比较两组治疗90 d内外周血基质金属蛋白酶-9(MMP -9)的变化,以及卒中和血管性意外事件的发生率。结果治疗21 d后,双抗组血液中M M P -9浓度下降值高于单抗组[(77.26±13.71)ng/ml比(96.86±16.52)ng/ml ,P<0.01]。双抗组90 d内脑梗死总复发率和同侧复发率均低于单抗组(3.88%比11.76%,P =0.035;1.94%比8.82%,P =0.029),两组对侧脑梗死复发率差异无统计学意义(1.94%比2.94%,P=0.643)。双抗组同单抗组相比,出血事件(0.97%比0,P>0.05)和急性冠脉综合征的发生率(1.94%比5.88%, P =0.145)差异均无统计学意义。结论对于伴易损斑块的症状性颈动脉狭窄患者,阿司匹林联合氯吡格雷双联抗血小板治疗相对阿司匹林单抗治疗更具优势。  相似文献   
65.
目的:回顾性总结应用颈动脉内膜切除术(CEA)治疗症状性颈动脉狭窄的早期效果和经验。方法:对82例(男66例,女16例,年龄48~84岁,平均68.6岁)症状性颈动脉狭窄病人行CEA。全组均经颈部血管多普勒超声和数字减影血管造影术(DSA)确诊颈动脉粥样斑块形成、颈动脉狭窄。手术采用气管内插管全身麻醉39例,颈丛麻醉43例。术中放置动脉临时转流管56例,其中全麻应用39例,颈丛麻醉17例。结果:全组无死亡病例,脑缺血症状明显改善者65例,症状好转者14例,术后并发脑梗死2例,颈动脉内血栓形成1例。结论:CEA是治疗症状性颈动脉狭窄的有效方法。  相似文献   
66.
目的 探讨数字眼底照相技术在脑小血管病临床初筛中的应用价值,为脑小血管病在基层社区临床 初筛提供依据。 方法 选取脑小血管病患者36例(72眼)为观察组,另选取30例(60眼)同期同年龄层非脑小血管病 的志愿者为对照组。比较两组一般资料、眼底血管改变和颈动脉斑块等情况。 结果 观察组眼底动静脉交叉征率(77.78% vs 23.33%)、眼底血管改变总发生率(88.89% vs 56.67%)、眼底动脉硬化3级比例(30.56% vs 0)均高于对照组(P <0.001,P =0.003,P =0.002)。 Logistic多元回归分析提示眼底动静脉交叉征是脑小血管病的重要危险因素[比值比(odds ratio,OR) 10.678,95%可信区间(confidence interval,CI )2.943~38.742,P <0.001]。观察组中有眼底血管改变者 32例,无眼底血管改变者4例,有眼底血管改变者的颈动脉斑块发生率、颈动脉斑块数均较无眼底 血管改变者高(P =0.010,P =0.013)。 结论 本研究中半数以上脑小血管病患者出现眼底动静脉交叉征,数字眼底照相技术或可作为脑小 血管病在基层社区临床初筛常规手段之一。  相似文献   
67.
Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
68.
This study investigated the role of dual-energy computed tomography (CT) for lesion characterization in patients with peripheral arterial disease manifesting with chronic total occlusions (CTOs). Forty-one symptomatic patients with CTOs underwent dual-energy CT angiography before endovascular treatment. The lesions were subsequently analyzed in a dedicated workstation, and 2 indexes—dual-energy index (DEI) and effective Z (Zeff)—were calculated, ranging from 0.0027 to 0.321 and from 6.89 to 13.02, respectively. Statistical analysis showed a significant correlation between the DEI and Zeff values (P < .001). The interobserver intraclass correlation coefficient was 0.91 for the mean Zeff values and 0.86 for the mean DEI values. This technique could potentially provide useful information regarding the composition of a CTO.  相似文献   
69.
An important advantage of computed tomography coronary angiography (CCTA) is its ability to visualize the presence and severity of atherosclerotic plaque, rather than just assessing coronary artery stenoses. Until recently, assessment of plaque subtypes on CCTA relied on visual assessment of the extent of calcified/non-calcified plaque, or visually identifying high-risk plaque characteristics. Recent software developments facilitate the quantitative assessment of plaque volume or burden on CCTA, and the identification of subtypes of plaque based on their attenuation density. These techniques have shown promise in single and multicenter studies, demonstrating that the amount and type of plaque are associated with subsequent cardiac events. However, there are a number of limitations to the application of these techniques, including the limitations imposed by the spatial resolution of current CT scanners, challenges from variations between reconstruction algorithms, and the additional time to perform these assessments. At present, these are a valuable research technique, but not yet part of routine clinical practice. Future advances that improve CT resolution, standardize acquisition techniques and reconstruction algorithms and automate image analysis will improve the clinical utility of these techniques. This review will discuss the technical aspects of quantitative plaque analysis and present pro and con arguments for the routine use of quantitative plaque analysis on CCTA.  相似文献   
70.
BackgroundPretest probability (PTP) calculators utilize epidemiological-level findings to provide patient-level risk assessment of obstructive coronary artery disease (CAD). However, their limited accuracies question whether dissimilarities in risk factors necessarily result in differences in CAD. Using patient similarity network (PSN) analyses, we wished to assess the accuracy of risk factors and imaging markers to identify ≥50% luminal narrowing on coronary CT angiography (CCTA) in stable chest-pain patients.MethodsWe created four PSNs representing: patient characteristics, risk factors, non-coronary imaging markers and calcium score. We used spectral clustering to group individuals with similar risk profiles. We compared PSNs to a contemporary PTP score incorporating calcium score and risk factors to identify ≥50% luminal narrowing on CCTA in the CT-arm of the PROMISE trial. We also conducted subanalyses in different age and sex groups.ResultsIn 3556 individuals, the calcium score PSN significantly outperformed patient characteristic, risk factor, and non-coronary imaging marker PSNs (AUC: 0.81 vs. 0.57, 0.55, 0.54; respectively, p ?< ?0.001 for all). The calcium score PSN significantly outperformed the contemporary PTP score (AUC: 0.81 vs. 0.78, p ?< ?0.001), and using 0, 1–100 and ?> ?100 cut-offs provided comparable results (AUC: 0.81 vs. 0.81, p ?= ?0.06). Similar results were found in all subanalyses.ConclusionCalcium score on its own provides better individualized obstructive CAD prediction than contemporary PTP scores incorporating calcium score and risk factors. Risk factors may not be able to improve the diagnostic accuracy of calcium score to predict ≥50% luminal narrowing on CCTA.  相似文献   
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