Low serum bilirubin concentrations are associated with impaired aortic elastic properties, but not impaired left ventricular diastolic function

Elevated serum bilirubin concentrations protect from atherosclerotic diseases; however, it is not clear whether higher serum bilirubin concentrations in physiological ranges do the same. To investigate the association of high and low serum bilirubin concentrations with left ventricular diastolic function and aortic elastic properties. We evaluated left ventricular diastolic function and aortic elastic properties of 42 healthy subjects with hypobilirubinemia (total bilirubin 0.40 ± 0.08 mg/dl; mean age 37.0 ± 3.9) and 40 healthy subjects with hyperbilirubinemia (total bilirubin 1.56 ± 0.49 mg/dl; mean age 36.2 ± 6.0) using transthoracic second harmonic Doppler echocardiography. Age, gender, body mass index and coronary risk factors were similar between the groups, except high‐sensitivity C‐reactive protein (hsCRP). Left ventricular diastolic parameters were similar between the two groups. Aortic distensibility (AoD) was found to be significantly lower (11.1 ± 3.9 vs. 13.2 ± 4.9, p = 0.03) and aortic stiffness index (AoSI) (1.99 ± 0.30 vs. 1.85 ± 0.26, p = 0.02) and elastic modulus (AoEM) (2.06 ± 0.83 vs. 1.73 ± 0.68, p = 0.03; the low and high bilirubin groups, respectively) higher in the low bilirubin group. Serum total bilirubin concentration correlated with hsCRP levels, AoD, AoSI and AoEM. In conclusion, left ventricular systolic and diastolic functions were similar between hypo‐ and hyperbilirubinemic subjects, but aortic elastic properties were impaired in subjects with lower serum bilirubin concentrations.     

Associations of methylenetetrahydrofolate reductase C677T polymorphism with markers of subclinical atherosclerosis: the Cardiovascular Risk in Young Finns Study

OBJECTIVE: To study whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism or serum homocysteine concentration is associated with carotid artery intima media thickness (IMT), carotid artery compliance (CAC) or brachial artery flow mediated dilatation (FMD) in a healthy Finnish adult population. METHODS: Cross-sectional data obtained in 2001 for the Cardiovascular Risk in Young Finns Study were used. Carotid artery IMT, CAC and brachial FMD were measured by ultrasound and serum homocysteine concentrations using a commercial immunoassay kit. We studied 1,440 subjects (aged 24-39 years). Genotyping was performed using the 5' nuclease TaqMan assay. RESULTS: Homocysteine values differed between genotypes in women and men (ANOVA, p<0.001 for both sex groups): the genotype raised values in the order of CC, CT, TT. There was a significant difference in CAC values between the MTHFR genotypes in men (ANOVA, p = 0.008), and the CC genotype had the lowest values. In multivariate linear regression analysis adjusted for other major coronary risk factors (e.g. age, smoking, body mass index, systolic blood pressure, C-reactive protein), the association remained significant (R (2) = 25.8 %, beta = 0.091; p = 0.02). Homocysteine level was directly associated with CAC in the whole population (R (2) = 18.0 %, beta = 0.012; p = 0.014) and in women (R (2) = 9.3%, beta = 0.02; p = 0.013), but not in men (R (2) = 15.2 %, beta = 0.004; p = 0.444). We found no association between homocysteine level or the MTHFR polymorphism and carotid IMT or brachial artery FMD. CONCLUSIONS: The findings suggest that the MTHFR polymorphism does not influence IMT or FMD, but that the T allele may have an effect on CAC in men.     

超声评价稳定型心绞痛患者颈总动脉结构及功能与肱动脉血管内皮功能的关系

目的探讨稳定型心绞痛患者肱动脉内皮功能与颈总动脉血流动力学、结构的改变及其相互关系。方法30例稳定型心绞痛患者和20例健康者对照组,超声检测并计算血流介导的肱动脉血管舒张功能（FMD）和硝酸甘油介导的肱动脉血管舒张功能（NMD）,颈总动脉内中膜复合体厚度（IMT）、弹性指数（Ep）、僵硬指数（p）及最大剪切率。结果与对照组比较,稳定型心绞痛组FMD降低,颈总动脉IMT增厚,Ep指数、β指数增高,最大剪切率降低,差异均有统计学意义（P〈0．01）。稳定型心绞痛FMD与颈总动脉IMT（r=-0．69,P〈0．01）、Ep指数（r=-0．48,P〈0．01）、β指数（r=-0．54,P〈0．01）呈负相关,与最大剪切率（r=0．57,P〈0．01）呈正相关。结论稳定型心绞痛患者颈动脉血流动力学及结构改变与肱动脉血管内皮功能的变化相关。     

A methodological study of arterial wall function using ultrasound technique

We aimed to establish reference values for three important properties of the arterial wall using a conventional ultrasound scanner. We measured: (1) intima–media thickness (IMT) of the carotid arteries with the internal trace function of the ultrasound system; (2) wall stiffness by pulsatile diameter changes in the right common carotid artery assessed by M-mode; and (3) endothelial function expressed as flow-mediated dilatation (FMD) of the brachial artery. IMT and wall stiffness measurements and reproducibility were compared with those obtained by external analysing systems. All variables were obtained in healthy subjects (n = 20), 29–53 years old. IMT increased with age (P<0·01). There was no difference in IMT between men and women. The inter-operator variability for measuring IMT was 6–9%. The same order of reproducibility was obtained with an external PC-based analysing system. Regarding wall stiffness, no correlation was found with age, nor any difference between men and women. A low intra-operator variability (CV < 10%) was found for measurements of wall stiffness with both M-mode and an external wall tracking system. FMD of the brachial artery diminished with age (P<0·01). There was a relation between FMD and brachial artery size (P<0·01) and, therefore, as men have larger arterial diameters (P<0·01), smaller FMD in men. We conclude that it is possible to characterize arterial wall function non-invasively in an adequately reproducible manner using a conventional ultrasound system in healthy middle-aged men and women.     

Cardiovascular magnetic resonance imaging for non-invasive assessment of vascular function: validation against ultrasound.

Ultrasound is an established modality for quantification of vascular function in clinical studies of cardiovascular disease. We determined whether cardiovascular magnetic resonance imaging (CMR) can provide a comparable assessment of vascular function. In seventeen control subjects, we used CMR to quantify endothelium-dependent (flow mediated dilatation, FMD) and endothelium-independent dilatation of the brachial artery, brachial and carotid distensibility, aortic compliance, and pulse wave velocity. These were compared to brachial and carotid measurements obtained by established ultrasound protocols. Twelve of the volunteers then underwent repeated measurements with both modalities. There was good agreement between imaging modalities for measures of endothelial function and arterial structure in the same subjects (difference between CMR and ultrasound for FMD = 0.14 +/- 6.8%, and brachial artery area = - 0.7 +/- 2.2 mm2, correlation between modalities for FMD = 0.62, p = 0.01 and for area = 0.87, p = < 0.0001). Inter-study reproducibility was also similar (coefficient of variation (CV) for FMD: CMR = 0.3, ultrasound = 0.3, CV for brachial artery area: CMR = 0.1, ultrasound = 0.1). Comparability and reproducibility were not as strong for functional measures if repeated studies were several days apart (CV for FMD by ultrasound on the same day = 0.1 and several days apart = 0.4). CMR and ultrasound show good agreement for quantitative measures of vascular structure and function with good reproducibility for both modalities. The major advantage of CMR is that it allows one-stop integrated assessment of both peripheral and central measures of vascular function.     

Tracking of Noninvasive Ultrasound Measurements of Subclinical Atherosclerosis in Adulthood: Findings from the Cardiovascular Risk in Young Finns Study

We examined tracking of ultrasound measurements of vascular structure and function in adulthood using data collected in the 2001 and 2007 follow-ups of Cardiovascular Risk in Young Finns Study. B-mode ultrasound measures of carotid artery intima-media thickness (IMT), carotid artery distensibility (CDist) and brachial artery flow-mediated dilatation (FMD) was obtained on 1809 apparently healthy Finnish adults aged 24 to 39 years in 2001 (1014 females; 795 males). Significant 6-year tracking was observed for IMT (males, r = 0.56; females, r = 0.46), CDist (males, r = 0.35; females, r = 0.36) and FMD (males, r = 0.23; females, r = 0.20). Subjects with 10-year risk of CVD (according to the SCORE risk score) above sex-specific median had improved IMT (r = 0.44; r = 0.57, p = 0.0001) and CDist (r = 0.31; r = 0.40, p = 0.03) tracking compared with those below median. Body mass index (BMI) ≥ 30 kg/m² decreased tracking of CDist (r = 0.36; r = 0.19, p = 0.01). In conclusion, ultrasound measurements tracked low to moderate over 6-years and was influenced by cardiovascular disease (CVD) risk factor status. (E-mail: juho.raiko@utu.fi)     

糖耐量低减患者颈动脉内-中膜厚度与肱动脉血管内皮舒张功能的超声研究

目的应用高频超声检查糖耐量低减（IGT）患者颈动脉内一中膜厚度（IMT）及肱动脉血管内皮舒张功能,对IGT患者早期动脉粥样硬化病变进行评估。方法高频超声检查50例IGT患者和50例正常对照组颈动脉IMT及粥样硬化斑块,同时检测肱动脉血流介导的内皮依赖性（EDD）及非内皮依赖性（EID）舒张功能,并进行对比分析。结果IGT患者颈动脉IMT及斑块发生率均高于正常对照组（P≤0．01）,IGT组内皮依赖性血管舒张功能较正常对照组减低（P〈0．01）;硝酸甘油介导的非内皮依赖性血管舒张功能两组间无差异（P〉0．05）。IGT组颈动脉IMT与年龄,体重指数及2h血糖、总胆固醇及低密度脂蛋白胆固醇水平,均呈正相关（P〈0．01）,与EDD呈负相关（P〈0．01）;经多元逐步回归,年龄和EDD是颈动脉IMT增厚的独立危险因素。结论高频超声检查IGT患者颈动脉IMT和肱动脉内皮舒张功能,可提供干预治疗及预防心血管疾病的客观依据。     

Brachial artery diameter is related to cardiovascular risk factors and intima-media thickness

Background  Previous reports showed inconsistent results about the potential role of flow-mediated dilatation (FMD) in cardiovascular(CV) risk prediction. Few data are available about the role of nitroglycerin-mediated dilatation (NMD), but recently, brachial artery diameter(BAD) appeared to have predictive value in CV risk prediction.We determined the relation of FMD, BAD and NMD with known CV risk factors and intima-media thickness (IMT), a well-established surrogate marker of atherosclerosis, in a community-based population, the Nijmegen Biomedical Study (NBS).
Materials and methods  FMD, BAD and NMD were measured in the brachial, and IMT in the common carotid artery ultrasononically in 337 participants, aged 50–70 years. Traditional clinical and biochemical parameters were determined.
Results  Both FMD and NMD were not correlated with most CV risk factors or prevalent CVD. However, both IMT and BAD did show significant correlations with CV risk factors. In accordance, both IMT and BAD were significantly correlated with prevalent CVD ( r  = 0·62 and r  = −0·37, respectively) . Furthermore, FMD was not correlated with IMT and did hardly ( R ² = 1·1%) improve the prediction of IMT by CV risk factors in regression analysis. However, both BAD and NMD did correlate with IMT ( r  = −0·29 and r  = 0·25, respectively).
Conclusion  In our study, FMD and NMD were not related to known CV risk factors and prevalent CVD, and FMD was not correlated with IMT, a surrogate marker of atherosclerosis. Most intriguingly, BAD was significantly correlated with some CV risk factors, prevalent CVD and IMT. So, BAD is a potential valuable tool in CV risk prediction in middle-aged low-risk populations, whereas FMD is not.     

2型糖尿病患者肱动脉内皮依赖性血管舒张功能、踝臂指数及颈动脉的检测分析

目的探讨2型糖尿病患者肱动脉内皮依赖性血管舒张功能(endothelium-dependenf,EDD)、踝臂指数(ankle brachial index,ABI)、颈动脉内膜中层厚度(inti ma-media thickness,IMT)的相关性及颈动脉血流动力学的改变。方法 31例健康志愿者为对照组,62例2型糖尿病患者分为两组:病程≤5年的患者为A组,病程>5年的患者为B组。利用高频超声检测所有观察对象肱动脉的EDD及颈动脉IMT、血流收缩期峰值血流速度(S)、舒张期末血流速度(D)、S/D、加速时间(AT)、阻力指数(RI),利用血压计测量所有观察对象的四肢血压,计算ABI。结果糖尿病A组较对照组EDD降低(P<0.01),两组间IMT、ABI及血流动力学参数的差异无统计学意义(P>0.05)。糖尿病B组与A组及对照组比较,IMT增厚(P<0.01),EDD、ABI降低(P<0.01),S/D升高(P<0.05),S、D降低(P<0.01),AT、RI均增高(P<0.01)。EDD与IMT呈负相关(r=-0.575,P<0.01),与ABI呈正相关(r=0.492,P<0.01),IMT与ABI之间呈负相关(r=-0.521,P<0.01)。结论糖尿病对EDD的损伤要早于IMT及ABI的改变;EDD的损伤加速了动脉粥样硬化的发展,导致IMT增厚和ABI下降,使血流动力学发生改变。     

温胆片改善高血压病血管内皮功能障碍的超声研究

目的 探讨温胆片对痰浊型原发性高血压病患者血管内皮功能障碍的调节作用.方法 选择低危、中危组痰浊型原发性高血压患者43例,按随机数字表法分为治疗组23例,对照组20例.在氨氯地平有效控制血压基础上治疗组口服温胆片,对照组口服安慰剂.应用彩超检测治疗前和治疗6个月后患者颈动脉内膜-中膜厚度(IMT),肱动脉充血性和含服硝酸甘油后肱动脉内径的变化.结果 治疗后内皮依赖性舒张功能改善治疗组优于对照组(P<0.05),但硝酸甘油诱发的非内皮依赖性舒张功能2组相比无显著性差异(P>0.05).痰浊型原发性高血压病患者肱动脉内皮依赖性舒张功能与颈动脉IMT呈负相关(r＝-0.596,P<0.05).结论 痰浊型高血压病颈动脉IMT与肱动脉内皮依赖性舒张功能呈负相关,温胆片对肱动脉内皮依赖性舒张功能异常有较好的改善作用.     

Investigation of early atherosclerotic changes in acromegalic patients

Background: Functional and morphological changes of endothelium were risk factors for mortality attributed to atherosclerosis. Studies investigating early atherosclerotic alterations and the effect of the treatment of acromegaly on these alterations gave conflicting results. Objective: Surrogate markers of early atherosclerotic changes, i.e. brachial artery flow‐mediated dilation (FMD) and carotid artery intima‐media‐thickness (IMT) in active and inactive acromegalic patients were compared with control subjects matched to patients for age, sex and cardiovascular risk factors to find out the direct effects of growth hormone (GH)/insulin‐like growth factor‐1 excess. Methods: In 14 active acromegalics and their 14 matched controls, 14 inactive acromegalics and their 14 matched controls, carotid artery IMT and FMD of brachial artery were measured. Inactive acromegalics were in remission for at least 1 year. Results: Active acromegalics had higher IMT than matched controls and inactive acromegalics (0.85 ± 0.20 mm, 0.64 ± 1.77 mm, 0.66 ± 0.20 mm respectively; p < 0.005, p < 0.05) and IMT of inactive acromegalics was not different from their matched controls (0.61 ± 0.12 mm). FMD was significantly lower in active acromegalics than in matched controls and inactive acromegalics (2.910 ± 2.00 mm, 6.5 ± 2.81 mm, 5.68 ± 2.9 mm respectively; p < 0.005, p < 0.05). FMD of inactive acromegalics was not significantly different from their matched controls (7.96 ± 3.12 mm). A significant inverse relationship was found between GH and FMD in active acromegalics (r = ?0.659, p = 0.010). Conclusion: In active acromegalics, early atherosclerotic changes are not only attributed to the high prevalence of risk factors, but also to the abnormal GH secretion itself.     

高血压患者血管内皮功能及颈动脉内膜中层厚度与室间隔厚度的关系

目的探讨高血压患者室间隔厚度与血管内皮功能及颈动脉内膜中层厚度的关系。方法选择中老年高血压患者85例,应用彩色多普勒超声检测心脏室间隔厚度、肱动脉内皮依赖性舒张功能(FMD)及颈动脉内膜中层厚度(IMT),根据室间隔厚度分为室间隔肥厚组和室间隔正常组,并测定一氧化氮(NO)、内皮素-1(ET-1)、空腹血糖、总胆固醇、低密度脂蛋白等生化指标,同时选择我院体检中心健康人群30名作为健康对照组。结果室间隔肥厚组FMD、NO含量较室间隔正常组及对照组显著降低,颈动脉IMT明显增厚,ET-1浓度明显增高,差异有统计学意义(P0.05)。相关性分析提示室间隔厚度与IMT(r=0.533)、ET-1(r=0.673)呈正相关,与FMD(-0.628)、NO(r=-0.629)呈负相关,颈动脉IMT与肱动脉FMD呈负相关(r=-0.706)。结论高血压患者存在血管功能障碍,且室间隔肥厚患者血管内皮功能及颈动脉损害程度更严重。     

Correlation between the intima-media thickness of the carotid artery and aortic pulse-wave velocity in patients with type 2 diabetes. Vessel wall properties in type 2 diabetes.

OBJECTIVE: The aim of this study was to assess the relationship between atherotic (structural) and sclerotic (functional) changes in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Aortic distensibility and carotid intimal-media thickness (IMT) were evaluated using carotid-femoral aortic pulse-wave velocity (a-PWV) and high-resolution B-mode ultrasonography in 271 patients with type 2 diabetes and 285 age-matched control subjects. RESULTS: a-PWV and carotid IMT were significantly higher in the patients than in the control subjects in all age-groups (P < 0.0001, respectively). The carotid IMT and a-PWV were significantly correlated with age in both the patients with type 2 diabetes and control subjects. There was a significant positive relationship between the carotid IMT and a-PWV in both the patients (r = 0.482, P < 0.0001) and control subjects (r = 0.424, P < 0.0001). The slope of the regression line for the carotid IMT to the a-PWV was significantly steeper in the diabetic patients than in the control subjects (P < 0.05). Multiple regression analysis in all subjects showed that age, diabetic state, and cigarette smoking were independently common risk factors for the increase in carotid IMT and a-PWV. In the diabetic patients, the independent risk factors associated with the carotid IMT were age, hyperlipidemia, and duration of diabetes (R2 = 0.232, P < 0.0001), while those associated with a-PWV were age and duration of diabetes (R2 = 0.334, P < 0.0001). CONCLUSIONS: The results indicated that diabetic patients showed more advanced changes in atherosis than that in sclerosis as compared with age- and sex-matched control subjects. Such atherotic changes in diabetic patients may be associated with hyperlipidemia.     

高血压合并颈动脉斑块患者内皮功能的变化及其影响因素

目的：评价高血压合并颈动脉斑块患者的内皮功能的变化并探讨可能的影响因素。方法选取2011年1月至2012年1月在我院就诊的高血压合并颈动脉斑块患者71例,同期选取来我院体检的健康者20例作为正常对照组。以血流介导的内皮依赖性血管舒张功能（ FMD）和硝酸甘油引起的非内皮依赖性血管舒张功能（NMD）作为内皮功能的检测指标。另外检测入选人群的内中膜厚度（IMT）、尿微量白蛋白、血清肌肝（Cr）、尿酸（UA）、血糖（Glu）、血脂、超敏C反应蛋白（hs-CRP）等生化指标,并计算尿白蛋白排泄率（ UAER ）、内生肌酐清除率（ Ccr ）。结果（1）两组间 FMD、NMD、IMT、收缩压（ SBP ）、舒张压（DBP）、Cr、UA、Glu、总胆固醇（TC）、低密度脂蛋白（LDL）、hs-CRP、UAER的对数（LgUAER）差异均有统计学意义（ P＜0.05）。（2）△FMD％与 SBP （ r ＝-0.442, P ＝0.000）、IMT （ r ＝-0.217, P ＝0.040）、Glu （ r ＝-0.356,P＝0.001）、TC （ r＝-0.381, P＝0.000）、LDL （ r＝-0.267, P＝0.011）、hs-CRP （ r＝-0.234, P＝0.026）、LgUAER（r＝-0.596,P ＝0.000）呈负相关;△NMD％与年龄（r ＝-0.207,P ＝0.049）、SBP（r ＝-0.271,P＝0.009）、IMT（r＝-0.296,P＝0.004）、Glu（r＝-0.220,P＝0.036）、LgUAER（r＝-0.311,P＝0.003）呈负相关。（3）多元线性回归分析 FMD 的主要危险因素是 UAER、TC （调整的 R2＝0.329, P ＝0.027）;NMD的主要危险因素是UAER、年龄（调整的R2＝0.076,P＝0.044）。结论高血压合并颈动脉斑块患者的内皮功能减低,UAER、TC、年龄是其内皮功能障碍的主要危险因素。     

Associations of methylenetetrahydrofolate reductase C677T polymorphism with markers of subclinical atherosclerosis: The Cardiovascular Risk in Young Finns Study

Objective. To study whether the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism or serum homocysteine concentration is associated with carotid artery intima media thickness (IMT), carotid artery compliance (CAC) or brachial artery flow mediated dilatation (FMD) in a healthy Finnish adult population. Methods. Cross‐sectional data obtained in 2001 for the Cardiovascular Risk in Young Finns Study were used. Carotid artery IMT, CAC and brachial FMD were measured by ultrasound and serum homocysteine concentrations using a commercial immunoassay kit. We studied 1,440 subjects (aged 24–39 years). Genotyping was performed using the 5′ nuclease TaqMan assay. Results. Homocysteine values differed between genotypes in women and men (ANOVA, p<0.001 for both sex groups): the genotype raised values in the order of CC, CT, TT. There was a significant difference in CAC values between the MTHFR genotypes in men (ANOVA, p = 0.008), and the CC genotype had the lowest values. In multivariate linear regression analysis adjusted for other major coronary risk factors (e.g. age, smoking, body mass index, systolic blood pressure, C‐reactive protein), the association remained significant (R² = 25.8?%, beta = 0.091; p = 0.02). Homocysteine level was directly associated with CAC in the whole population (R² = 18.0?%, beta = 0.012; p = 0.014) and in women (R² = 9.3%, beta = 0.02; p = 0.013), but not in men (R² = 15.2?%, beta = 0.004; p = 0.444). We found no association between homocysteine level or the MTHFR polymorphism and carotid IMT or brachial artery FMD. Conclusions. The findings suggest that the MTHFR polymorphism does not influence IMT or FMD, but that the T allele may have an effect on CAC in men.     

Impaired brachial endothelial function in patients with primary anti-phospholipid syndrome

Although the precise pathophysiology of thrombosis is unknown in primary anti-phospholipid syndrome (PAPS), it is assumed that autoantibodies developed against endothelial cells and platelets might be one of the primary mechanisms. However, whether interaction between autoantibodies and endothelium leads to an impaired vasodilator response has not been investigated yet. In this study, we aimed to investigate the endothelial functions in patients with PAPS. Thirty-one patients with PAPS (22 female, nine male, mean age: 34.6+/-8.9 years) and 27 age- and sex-matched, healthy controls were included in the study. Brachial artery responses to reactive hyperaemia (endothelium-dependent dilatation) [EDD] and sublingual nitroglycerine (endothelium-independent dilatation) [EID] were measured by using high-resolution vascular ultrasound both in patients with PAPS and in the controls. The results were expressed as percentage of change in baseline values. Regarding cardiovascular risk factors, there was no significant difference between the two groups. EDD in patients with PAPS was significantly lower than those of controls (6.9+/-4.9 vs. 14.8+/-4.1%; p<0.0001). EID measurements were not significantly different between the groups. In the PAPS group, EDD in patients with arterial involvement (17 patients) was significantly lower than those of patients with venous involvement (12 patients) (4.6+/-3.9 vs. 7.4+/-4.1%; p = 0.02). This study showed that endothelial functions determined by using brachial artery ultrasound were impaired in patients with PAPS, and this was more prominent in the subgroup of patients with arterial involvement compared to patients with venous involvement.     

Automated edge detection versus manual edge measurement in analysis of brachial artery reactivity: a comparison study

High resolution ultrasound, combined with computer imaging technology, is commonly used to measure changes in brachial artery diameter for the determination of endothelial-dependent vasodilation (EDD) and endothelial independent-vasodilation (EID). Currently, two methods of computerized edge-detection systems are in use to measure changes in artery diameter. One system involves the sonographer manually tracking the artery walls while the second system involves a computer automated edge-detection system that automatically tracks the artery wall. The purpose of this study was to compare the two types of computerized edge-detection systems for measuring vascular function and structure. One hundred fifty (female = 70, male = 80) participants agreed to participate. Baseline brachial diameter, carotid intima-medial thickness (cIMT), EDD and EID were measured by the two computerized edge-detection systems utilizing the same ultrasound B-mode image. Mean values (+/-standard error) for baseline diameter, cIMT, EDD and EID were 3.53 (+/-0.10) mm, 0.43 (+/-0.01) mm, 5.72 (+/-0.20)% and 22.17 (+/-0.60)%, respectively for the manual edge-detection software system. Mean values for baseline diameter, cIMT, EDD and EID were 3.59 (+/-0.10) mm, 0.44 (+/-0.01) mm, 7.33 (+/-0.30)% and 25.77 (+/-0.60)%, respectively for the automated edge-detection software system. Bland-Altman plots displayed large variations between the two edge-detection methods for assessing cIMT and changes in artery diameter following brachial EDD and EID. The results of the study demonstrate that manual and automated computerized edge-detection systems track dynamic changes in brachial artery diameter and cIMT measures differently. Therefore, caution should be used when comparing research utilizing different computerized edge-detection systems for measuring vascular function and structure. (E-mail: will0188@umn.edu).     

吸烟者血管内皮舒张功能与颈、股动脉内-中膜厚度相关性的超声研究

目的探讨吸烟者肱动脉流量介导的舒张功能(FMD)与颈、股动脉内-中膜厚度(IMT)的相关性。方法利用高频超声检测34例健康吸烟者及34例健康不吸烟者肱动脉流量介导的舒张功能及颈、股动脉内-中膜厚度。结果健康吸烟者肱动脉FMD明显低于对照组,并且健康吸烟者颈、股动脉IMT明显高于对照组,与颈、肱动脉FMD呈负相关。结论吸烟可导致动脉内皮功能障碍,高频超声能够早期发现吸烟者动脉内皮功能障碍,健康吸烟者无心血管疾病症状时已有颈、股动脉内-中膜厚度的改变。     

Impaired endothelium-dependent flow-mediated dilation in Behçet's disease: more prominent endothelial dysfunction in patients with vascular involvement

Brachial artery endothelial dysfunction was shown previously in a small group of Behçet's disease (BD) patients. This study aimed to compare the endothelial function in BD patients with and without vascular involvement. The study group consisted of 25 BD patients with vascular involvement, 25 BD patients without any vascular disease and 46 healthy controls. Brachial artery flow‐mediated (endothelium‐dependent) dilation (FMD), nitroglycerine‐induced dilation and carotid artery intima‐media thickness were measured. FMD was impaired in patients with BD (10.41 ± 3.85%) compared to healthy controls (14.41 ± 3.39%, p < 0.001). FMD was significantly lower in BD patients with vascular involvement (8.80 ± 3.63%) than those without any vascular disease (12.02 ± 3.43%, p = 0.003). This study reveals that endothelial dysfunction documented by brachial artery FMD is a feature of BD, and it is more prominent in patients with vascular involvement.     

流量介导的肱动脉扩张和颈动脉内中膜厚度对冠心病患者发生心血管事件的预测作用

目的探讨流量介导的肱动脉扩张（FMD）和颈动脉内中膜厚度（IMT）能否预测冠心病患者心血管事件的发生。方法150例经冠状动脉造影明确患有冠心病的患者作为观察对象,分别测量每位患者的肱动脉FMD和颈动脉IMT,随访24个月,观察150例患者心血管事件的发生率,并比较心血管事件发生者与未发生者肱动脉FMD和颈动脉IMT的差别。结果150例患者中有21例在24个月的随访时间内发生心血管事件,未发生心血管事件者的肱动脉FMD较发生心血管事件者低,颈动脉IMT在未发生心血管事件者和发生心血管事件者中相差不显著（P〉0．05）。结论肱动脉FMD可以帮助预测冠心病患者心血管事件的发生。