高频体表超声检测急性冠状动脉综合征患者颈动脉结构及功能

应用高频体表超声观察急性冠状动脉综合征患者颈动脉结构及血管内皮功能的变化 ,探讨动脉粥样硬化结构和功能与急性冠状动脉综合征的关系。对 35例急性冠状动脉综合征患者检测了颈动脉粥样硬化斑块、内膜中膜厚度、肱动脉内皮功能的变化 ,并与 2 7例稳定型心绞痛及 31例正常对照组进行比较。结果发现 ,内膜中膜厚度和内皮依赖性血管舒张功能在急性冠状动脉综合征组 (分别为 0 .10± 0 .0 2和 3.98± 1.6 5 )和稳定型心绞痛组(分别为 0 .11± 0 .0 4和 4 .76± 2 .37)与对照组 (分别为 0 .0 7± 0 .0 1和 9.33± 3.4 7)有显著差异 (P <0 .0 5 ) ,斑块积分和斑块指数在急性冠状动脉综合征组 (分别为 4 .0 6± 2 .2 1和 3.14± 1.97)与稳定型心绞痛组 (分别为 4 .17± 1.76和3.2 1± 1.88)间无差异 (P >0 .0 5 ) ,急性冠状动脉综合征组颈动脉粥样硬化斑块以不稳定型为主。研究结果提示 ,外周血管超声检查可观察动脉粥样硬化病变 ,颈动脉结构及血管内皮功能与冠状动脉粥样硬化有关。     

Comparison of carotid intima-media thickness in patients with stable angina pectoris versus patients with acute coronary syndrome

In this study, we found that carotid intima-media thickness (IMT) was significantly increased and carotid artery atherosclerotic plaques were detected more frequently in patients who had early-onset coronary artery disease compared with control subjects (0.73 +/- 0.10 vs 0.60 +/- 0.10 mm, p <0.001, and 40% vs 11%, p <0.001, respectively). Further, patients who had coronary artery disease and presented with an acute coronary syndrome were found to have significantly increased carotid IMT compared with patients who had stable angina pectoris (0.76 +/- 0.10 vs 0.70 +/- 0.10 mm, p <0.05). The IMT was greater in the patients who had acute coronary syndrome than in those who had stable angina pectoris.     

Impaired endothelium-dependent vasodilation in the brachial artery in variant angina pectoris and the effect of intravenous administration of vitamin C

Endothelial dysfunction in the coronary artery contributes to the pathogenesis of variant angina, and endothelial dysfunction in variant angina may be associated with increased oxidant stress in the systemic arteries. We investigated whether endothelial dysfunction exists in the peripheral artery in patients with variant angina, and also examined the effect of vitamin C, an antioxidant, on endothelium-dependent vasodilation. Using high-resolution ultrasound, both the flow-mediated vasodilation (FMD, endothelium-dependent vasodilation) and sublingual nitroglycerin-induced vasodilation (NTG-D, endothelium-independent vasodilation) in the brachial artery were measured in 28 patients with variant angina and 24 control subjects who had normal coronary arteries. FMD was significantly impaired in patients with variant angina compared with control subjects (1.8 +/- 2.2% vs 6.4 +/- 4.9%, p <0.001). FMD and NTG-D before and after intravenous administration of either vitamin C or placebo were measured in 17 patients with variant angina. FMD significantly improved after the administration of vitamin C (from 2.2 +/- 2.4% to 4.5 +/- 1.6%, p <0.01), but not after administration of the placebo (from 2.0 +/- 2.6% to 1.7 +/- 1.9%). The improved FMD due to vitamin C in patients with variant angina, however, was not significantly different from that in the control subjects. NTG-D was not significantly different between patients with variant angina and control subjects (14.0 +/- 7.8% vs 13.6 +/- 5.0%) and it was also not affected by vitamin C. In conclusion: (1) FMD in the brachial artery is impaired in patients with variant angina, and (2) the acute administration of the antioxidant, vitamin C, was observed to reverse this endothelial dysfunction. These findings support the theory that the systemic inactivation of nitric oxide due to oxidative stress might exist in patients with variant angina.     

External counterpulsation therapy improves endothelial function in patients with refractory angina pectoris

OBJECTIVES: The goal of this study was to investigate the influence of short-term external counterpulsation (ECP) therapy on flow-mediated dilation (FMD) in patients with coronary artery disease (CAD). BACKGROUND: In patients with CAD, the vascular endothelium is usually impaired and modification or reversal of endothelial dysfunction may significantly enhance treatment. Although ECP therapy reduces angina and improves exercise tolerance in patients with CAD, its short-term effects on FMD in patients with refractory angina pectoris have not yet been described. METHODS: We prospectively assessed endothelial function in 20 consecutive CAD patients (15 males), mean age 68 +/- 11 years, with refractory angina pectoris (Canadian Cardiovascular Society [CCS] angina class III to IV), unsuitable for coronary revascularization, before and after ECP, and compared them with 20 age- and gender-matched controls. Endothelium-dependent brachial artery FMD and endothelium-independent nitroglycerin (NTG)-mediated vasodilation were assessed before and after ECP therapy, using high-resolution ultrasound. RESULTS: External counterpulsation therapy resulted in significant improvement in post-intervention FMD (8.2 +/- 2.1%, p = 0.01), compared with controls (3.1 +/- 2.2%, p = 0.78). There was no significant effect of treatment on NTG-induced vasodilation between ECP and controls (10.7 +/- 2.8% vs. 10.2 +/- 2.4%, p = 0.85). External counterpulsation significantly improved anginal symptoms assessed by reduction in mean sublingual daily nitrate consumption, compared with controls (4.2 +/- 2.7 nitrate tablets vs. 0.4 +/- 0.5 nitrate tablets, p <0.001 and 4.5 +/- 2.3 nitrate tablets vs. 4.4 +/- 2.6 nitrate tablets, p = 0.87, respectively) and in mean CCS angina class compared with controls (3.5 +/- 0.5 vs. 1.9 +/- 0.3, p <0.0001 and 3.3 +/- 0.6 vs. 3.5 +/- 0.5, p = 0.89, respectively). CONCLUSIONS: External counterpulsation significantly improved vascular endothelial function in CAD patients with refractory angina pectoris, thereby suggesting that improved anginal symptoms may be the result of such a mechanism.     

Systemic endothelial function is preserved in men with both active and inactive variant angina pectoris

To test the hypothesis that coronary spasm could be a coronary manifestation of systemic endothelial dysfunction and that the activity of coronary spasm could influence systemic endothelial function, we examined brachial flow-mediated, endothelium-dependent vasodilation and nitroglycerin-induced endothelium-independent vasodilation with high-resolution ultrasound in 11 men with variant angina pectoris (6 active and 5 inactive) without established coronary atherosclerosis. Endothelium-dependent vasodilation in peripheral circulation was preserved in men with active and inactive variant angina pectoris, suggesting that systemic endothelial dysfunction is not involved in either the pathogenesis or the activity of coronary spasm.     

Vitamin E administration improves impairment of endothelium-dependent vasodilation in patients with coronary spastic angina

Objectives. We examined the effects of oral administration of vitamin E, an antioxidant, on endothelium-dependent vasodilation in patients with coronary spastic angina.Background. We have recently reported that endothelium-dependent vasodilation is impaired in patients with coronary spastic angina (CSA). Furthermore, it is known that oxidative stress may play an important role in the impairment of endothelium-dependent vasodilation in cardiovascular diseases.Methods. With the ultrasound technique, flow-dependent vasodilation of the brachial arteries during reactive hyperemia was examined before and after treatment for a month with either oral administration of vitamin E (α-tocopherol acetate, 300 mg/day) or placebo, which is randomly assigned, in patients with CSA (n = 60).Results. Before treatment, patients with CSA had impaired flow-dependent vasodilation, lower plasma levels of α-tocopherol and higher plasma levels of thiobarbituric acid reactive substances (TBARS), as compared with age- and sex-matched control subjects (n = 60) (flow-dependent vasodilation: 3.1 ± 1.8 vs. 7.1 ± 2.5%, p < 0.001; α-tocopherol levels: 8.9 ± 1.8 vs. 10.8 ± 1.8 μg/ml, p < 0.001). In patients with CSA, treatment with vitamin E restored flow-dependent vasodilation (3.1 ± 1.7 vs. 8.3 ± 2.0%, p < 0.001), and this improvement was associated with the decreases in plasma TBARS levels and anginal attacks.Conclusions. The results indicate that vitamin E treatment improved endothelium-dependent vasodilation and decreased plasma TBARS levels in patients with CSA. Thus, increased oxidative stress may contribute to endothelial dysfunction and anginal attacks in patients with CSA.     

Baroreflex sensitivity normalization after cardiac resynchronization therapy

To evaluate the relation between peripheral vascular endothelial function and coronary flow reserve (CFR), we assessed flow mediated dilation (FMD) of brachial artery and the intima-media thickness (IMT) of the carotid artery in 32 subjects (mean age 58+/-9 years, M/F=9:23 ) with chest pain and normal coronary angiogram. The subjects were divided into 2 groups according to CFR >or=2.1 or <2.1 measured with transthoracic echocardiography in distal left anterior descending coronary artery. We found % FMD was decreased in the group with CFR <2.1 than those of CFR >or=2.1 and CFR was correlated with peripheral FMD. However, IMT was not different between two groups. These results suggest that microvascular dysfunction is primarily related to endothelial dysfunction rather than advanced atherosclerosis and because it is a generalized process that involves the whole arteries, the measurement of brachial FMD can be a useful diagnostic tool to evaluate microvascular dysfunction in patients with chest pain and normal coronary angiogram.     

老年女性冠心病患者颈动脉粥样硬化和血管内皮依赖性舒张功能的探讨

目的　观察老年女性冠心病患者颈动脉内中膜厚度 (IMT)、粥样斑块发生率及肱动脉内皮依赖性舒张功能的情况。方法　用高分辨超声技术对 89例老年女性行肱动脉血流介导的舒张功能 (FMD)、IMT及颈动脉粥样斑块的检测。结果　老年女性冠心病组FMD较对照组明显减弱 ,分别为 (3.5± 3.1) %及 (7.6± 3.5 ) % ,P <0 .0 0 1,老年女性冠心病组及对照组IMT分别为 (0 .88± 0 .2 0 )mm及 (0 .6 5± 0 .2 3)mm ,颈动脉粥样斑块发生率分别为 6 2 .2 %及11.4 % ,两组比较差异具有显著性意义 ,P <0 .0 0 1。结论　老年女性冠心病患者存在着严重的血管内皮依赖性舒张功能障碍以及颈动脉粥样硬化 ,颈动脉B超及肱动脉血流介导的舒张功能对老年女性冠心病患者有一定的预测价值。     

Relation of vasodilator response of the brachial artery to inflammatory markers in patients with coronary artery disease

Endothelial dysfunction of the coronary artery is closely related to elevated levels of systemic inflammatory markers and cardiovascular events in patients with coronary artery disease (CAD). We hypothesized that patients with CAD may have a higher risk of endothelial dysfunction of the peripheral artery than patients without evidence of CAD, and that endothelial dysfunction of the peripheral artery also may be related to elevated levels of inflammatory markers. Using high resolution ultrasound, we assessed the brachial vasodilator response to reactive hyperemia (endothelium-dependent) and sublingual nitroglycerin (endothelium-independent). As inflammatory markers, serum C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) levels, and lipid profiles were measured in patients with CAD (n = 30, 16 male and 14 female) and normal subjects without evidence of CAD (n = 45, 23 male and 22 female). Patients with CAD (Group II) showed a significantly reduced endothelium-dependent vasodilation as compared with normal subjects (Group I) (4.4 +/- 3.6 vs 7.4 +/- 6.1%, P < 0.05). However, endothelium-independent vasodilation was not significantly different between the two groups (7.7 +/- 7.1 vs 9.7 +/- 8.0%, P > 0.05). In Group II, CRP level was inversely related to endothelium-dependent vasodilation (r = -0.398, P = 0.029). In contrast, ESR level was not significantly associated to endothelium-dependent vasodilation (r = -0.113, P = 0.552). On multivariate analysis, CRP and low density lipoprotein cholesterol levels were significant independent predictors of a blunted endothelium-dependent vasodilation in Group II. Our study showed that elevated CRP level was associated with blunted endothelium-dependent vasodilation of the brachial artery in patients with CAD. Thus, identification of elevated CRP levels combined with demonstration of endothelial dysfunction of the brachial artery may have a possible clinical application for the detection of high risk CAD patients.     

Brachial artery flow-mediated vasodilation in patients with cardiac syndrome X

Cardiac syndrome X (CSX) differs from coronary artery disease (CAD) and is characterized by angina, positive stress test, and patent coronary arteries. The probable mechanism is a microvascular disorder associated with endothelial dysfunction. In this study, brachial artery flow-mediated vasodilation was used as well as the endothelin-1 assay to assess endothelial function in patients with cardiac syndrome X (CSX), coronary artery disease (CAD), and healthy controls. All subjects underwent a 2-step brachial artery flow-related vasodilatation test. Serum endothelin-1, one of the most potent constricting factors, was measured for all participants. Patients with CSX had a lower brachial artery dilation ratio than controls but higher than that of CAD patients. Control subjects and CSX patients had higher endothelin-1 levels than CAD patients. CSX patients were found to have worse endothelial function than healthy volunteers, but patients with CAD had even worse endothelium function than CSX patients.     

内皮功能变化与冠状动脉病变程度相关研究

目的探讨内皮功能变化与冠状动脉病变程度的关系。方法冠状动脉造影确定冠心病患者37例,其中稳定型心绞痛组17例,不稳定型心绞痛组20例。对照组23例,测定血清内皮素-1(ET-1)、一氧化氮(NO)浓度,及肱动脉内皮依赖性舒张功能(FMD),冠状动脉病变程度采用Gensini积分。结果冠心病组ET-1显著升高,NO、FMD显著降低,不稳定型心绞痛组较稳定型心绞痛组NO降低有显著性意义。NO、ET-1、FMD均与冠脉病变Gensini积分明显相关。结论冠心病患者血管内皮功能受损,其受损程度与冠脉病变严重程度有关。     

Enhanced coronary calcification determined by electron beam CT is strongly related to endothelial dysfunction in patients with suspected coronary artery disease

BACKGROUND: Coronary artery calcification determined by electron beam CT (EBCT) is strongly associated with total plaque burden but is not related to systemic vascular inflammation.Aims: We sought to test the hypothesis that enhanced coronary artery calcification, a marker of atherosclerosis and plaque burden, was related to endothelial dysfunction in patients with suspected coronary artery disease (CAD). METHODS AND RESULTS: One hundred twenty-four subjects with suspected CAD were enrolled. Coronary artery calcification was detected by EBCT. A noninvasive method of brachial ultrasound was used to measure endothelium-dependent flow-mediated vasodilation (FMD) and endothelium-independent nitroglycerin-mediated vasodilation (NMD). Serum high-sensitivity C-reactive protein (hsCRP) and monocyte chemoattractant protein-1 (MCP-1) levels were also determined. Of the 124 patients, the calcium scores ranged from 0 to 4,394. All subjects were classified into three groups according to coronary calcium scores: group 1, score 0 (n = 26); group 2, scores 1 to 199 (n = 50); group 3, scores > or = 200 (n = 48). There was an inverse association between the degree of coronary artery calcification and the endothelium-dependent FMD in the three groups (6.9 +/- 0.6% vs 5.3 +/- 0.3% vs 3.7 +/- 0.3%, respectively; p < 0.001) but not the endothelium-independent NMD. Besides, no significant difference in serum levels of hsCRP and MCP-1 were found among the three groups. However, both the serum levels of hsCRP and MCP-1 were correlated significantly with endothelium-dependent FMD (r = - 0.211, p = 0.019; and r = - 0.188, p = 0.037, respectively). By multivariate analysis, enhanced coronary calcification was a strong independent predictor of endothelial dysfunction (p < 0.001). CONCLUSION: Enhanced coronary artery calcification strongly predicted endothelial dysfunction in patients with suspected CAD. Also, serum levels of hsCRP and MCP-1 were significantly correlated with endothelial function. These findings suggested that both calcium deposition and inflammation were involved in endothelial dysfunction.     

Effects of angiotensin-converting enzyme inhibition on exercise-induced angina and ST segment depression in patients with microvascular angina

Objectives. This study was conducted to test the hypothesis that angiotensin-converting enzyme inhibition may lessen myocardial ischemia in patients with microvascular angina.Background. Patients with syndrome X (angina pectoris, positive findings on exercise testing and normal coronary arteriogram) have reduced coronary vasodilator reserve (“microvascular angina”, and may show an increased sympathetic drive. Angiotensin-converting enzyme inhibition attenuates sympathetic coronary vasoconstriction in patients with coronary artery disease.Methods. Ten patients (seven women and three men, mean age [±SD] 53 ± 6 years) with syndrome X and a reduced coronary flow reserve underwent a randomized, single-blind, crossover, placebo-controlled study of the effects of the angiotensin-converting enzyme inhibitor enalapril on angina and exercise-induced ST segment depression. Assessment was by symptom-limited treadmill exercise testing after 2 weeks of treatment with 10 mg/day of enalapril and after 2 weeks of placebo administration.Results. All patients had positive findings on exercise testing (≥1 mm ST segment depression and angina) white taking placebo, whereas six patients had a positive test results (four with angina) during enalapril therapy. Total exercise duration and time to 1 mm of ST segment depression were prolonged by enalapril over those obtained with placebo (mean 779 ± 141 vs. 690 ± 148s, p = 0.006 and 690 ± 204 vs. 485 ± 241 s, p = 0.007, respectively). The magnitude of ST segment depression was also less with enalapril than with placebo (mean 1.1 ± 0.4 vs. 1.5 ± 0.2 mm, p = 0.004). Heart rate and blood pressure at peak exercise and at 1 mm of ST depression were not significantly different during placebo and enalapril treatment.Conclusions. Angiotensin-converting enzyme inhibition lessens exercise-induced ischemia in patients with syndrome X and microvascular angina, probably by a direct modulation of coronary microvascular tone, which results in an increased myocardial oxygen supply.     

Impaired endothelial function in patients with rapidly stabilized unstable angina: assessment by noninvasive brachial artery ultrasonography.

BACKGROUND: Endothelial dysfunction may contribute to symptoms of instability in patients with acute coronary syndromes. High-resolution external ultrasound assessment of the brachial artery responses allows noninvasive determination of endothelial function. HYPOTHESIS: This study was conducted to assess endothelial function in patients with unstable angina using a noninvasive technique. METHODS: We studied 189 patients who were subdivided into three groups. Group 1: 60 apparently healthy subjects with no cardiovascular risk factors or symptoms of coronary artery disease; Group 2: 105 subjects with cardiovascular risk factors--arterial hypertension, hypercholesterolemia, cigarette smoking, diabetes, and obesity, but no evidence of coronary artery disease; and Group 3: 24 patients with unstable angina (chest pain at rest within the 24 h preceding study entry). All patients underwent pre- and postischemic brachial artery test evaluation with measurements of internal arterial diameters and blood flow. RESULTS: Results are expressed as percentage change from basal values. Subjects in Groups 1 and 2 showed a diameter increase of 19.1 and 11.9%, respectively, whereas patients in Group 3 showed a diameter change of 1.2% (p < 0.002 and < 0.0001, respectively). Calculated blood flow did not differ significantly in Groups 1 or 2 (74.4 and 56.4%), but was notably lower in Group 3 (18.4%, p < 0.005 vs. Groups 1 and 2). In nine patients of Group 3, the brachial studies were repeated 4 weeks after symptom stabilization and showed values comparable with those in Group 2. CONCLUSIONS: Patients with unstable angina showed endothelial dysfunction compared with control individuals. It is of interest that in patients whose symptoms were stabilized by medical therapy, endothelial function was restored 4 weeks after hospital discharge.     

Endothelial Tissue-Type Plasminogen Activator Release in Coronary Heart Disease: Transient Reduction in Endothelial Fibrinolytic Reserve in Patients With Unstable Angina Pectoris or Acute Myocardial Infarction

Objectives. We sought to examine whether the disturbed fibrinolytic system in patients with an acute coronary syndrome is associated with a reduced endothelial fibrinolytic capacity.Background. Intracoronary thrombus formation is a frequent finding in acute coronary syndromes. Systemic alterations of coagulation and fibrinolysis are known to occur, but possible disturbances of endothelial fibrinolytic function have not been investigated.Methods. We compared 42 patients with an acute coronary syndrome (acute myocardial infarction in 11 and unstable angina pectoris in 31) with 25 patients with stable angina. Venous blood was sampled serially for determination of markers of the fibrinolytic system and of hypercoagulability from admission to day 10. An occlusion test to determine the maximal endothelial tissue-type plasminogen activator (t-PA) release was also performed.Results. Both on day 0 and day 10, patients with an acute coronary syndrome had a marked elevation of t-PA mass concentration (mean value ± SEM 14.4 ± 1.6 [day 0], 18.9 ± 2.5 ng/ml [day 10]) and of plasminogen activator inhibitor (PAI) (9.4 ± 2.2 [day 0], 11.3 ± 2.6 AU/liter [day 10], p < 0.05 vs. patients with stable angina). There was also a hypercoagulative state with elevated thrombin activity and increased D-dimers (p < 0.05 vs. patients with stable angina). Maximal endothelial t-PA release was initially reduced (p < 0.05 vs. patients with stable angina) to 2.3 ± 0.9 ng/ml, but levels recovered during follow-up to 4.4 ± 1.4 ng/ml (vs. 5.7 ± 1.5 ng/ml in patients with stable angina).Conclusions. Despite the known prolonged systemic alteration of fibrinolysis in acute coronary syndromes, endothelial fibrinolytic capacity is reduced only during the acute phase and becomes normalized during follow-up, and thus is linked more to intravascular thrombus formation than to steady state levels of markers of the fibrinolytic system.     

Structural and functional changes in peripheral vasculature of Fabry patients

Summary Objective: Fabry disease is a lysosomal storage disorder due to deficient α-galactosidase A activity, which leads to glycosphingolipid accumulation especially in vascular smooth-muscle and endothelial cells. Little is known about the effects of Fabry disease on peripheral artery function and structure. Therefore, we aimed to further characterize the peripheral vascular structural and functional changes in Fabry disease. Methods and results: We measured structural and functional vascular parameters, including intima-media thickness (IMT) of brachial and carotid arteries and abdominal aorta, carotid and aortic compliance, and brachial artery flow-mediated dilatation (FMD) in 17 Fabry patients and 34 healthy controls matched for age, sex and smoking. Carotid IMT (0.64 ± 0.15 vs 0.57 ± 0.12 mm), brachial IMT (1.02 ± 0.25 vs 0.74 ± 0.18 mm), and aortic IMT (0.31 ± 0.09 vs 0.26 ± 0.04 mm) were significantly increased, and brachial FMD was significantly impaired (6.3 ± 5.0 vs 9.7 ± 3.9%) in Fabry patients compared to healthy controls (p < 0.05 in all comparisons after adjustments for age, LDL-cholesterol, and systolic blood pressure). No differences were observed in arterial compliance between the groups. Conclusions: These data suggest that Fabry disease affects arterial function and structure by disturbing peripheral endothelial function and promoting intima-media thickening. Competing interests: None declared     

Noninvasive assessment of endothelial dysfunction by brachial artery flow-mediated dilatation in prediction of coronary artery disease in Indian subjects

BACKGROUND: A noninvasive technique for testing endothelial function by ultrasound measurement of flow-mediated dilatation has recently generated considerable interest as a marker of atherosclerosis, and in the prediction of clinical coronary events and coronary artery disease. METHODS AND RESULTS: We measured the flow-mediated dilatation of the brachial artery (endothelium-dependent vasodilatation) in 136 subjects, with or without evidence of coronary artery disease. Endothelial dysfunction was diagnosed if flow-mediated dilatation was less than 4.5%. Of the 136 subjects (age group 40-70 years) recruited for the study, 94 were males and 42 females. Sixty-eight subjects had evidence of coronary artery disease as diagnosed by documented hospitalization due to myocardial infarction or acute coronary syndrome, proved by coronary angiography when feasible or noninvasive cardiac evaluation. Endothelial dysfunction was detected in 90 subjects (66.2%). Prevalence of coronary artery disease was higher among subjects with endothelial dysfunction compared to those without (57.5% v. 34.7%, p=0.013). Prevalence of endothelial dysfunction was significantly higher among subjects with coronary artery disease as compared to those without coronary artery disease (76.4% v. 55.8%, p=0.012). The present study showed a sensitivity of 76%, specificity of 44%, positive predictive value of 58% and negative predictive value of 65% for endothelial dysfunction in the prediction of coronary artery disease. Multiple regression analysis using coronary artery disease as a dependent variable revealed a statistically significant association with endothelial dysfunction (p=0.033) even after the inclusion of traditional risk factors into the model. CONCLUSIONS: We conclude that endothelial dysfunction shows a strong association with coronary artery disease and can be a useful noninvasive tool for the evaluation of coronary artery disease.     

可溶性OX40配体与颈动脉内膜中膜厚度的关系

目的 观察冠心病稳定型心绞痛患者及高危因素患者血浆中可溶性OX40配体水平,同时测定颈动脉内膜中膜厚度,分析两者的相关性,进一步探讨可溶性OX40配体与冠心病的关系.方法 采用酶联免疫吸附法测定35例稳定型心绞痛患者、30例高危因素者及20例正常对照者血浆中可溶性OX40配体浓度,同时利用彩色超声仪测量颈动脉内膜中膜厚度.结果 稳定型心绞痛患者血浆可溶性OX40配体水平(24.95±15.60 ng/L)高于正常对照者(16.44±11.31 ng/L;P<0.05);稳定型心绞痛患者和高危因素者的颈动脉内膜中膜厚度高于正常对照者(P<0.05),且与血浆可溶性OX40配体显著正相关(r=0.376,P=0.001).多因素回归分析显示,在控制年龄、血脂及血压影响后,可溶性OX40配体水平对内膜中膜厚度有独立的贡献(P=0.019).结论 冠心病患者可溶性OX40配体水平显著增高,且与颈动脉内膜中膜厚度独立相关,提示可溶性OX40配体可作为判断冠心痛及动脉粥样硬化新的炎症指标.     

Increased levels of soluble adhesion molecules E-selectin and P-selectin in patients with cardiac syndrome X

The role of endothelial dysfunction and platelet activation in patients with cardiac syndrome X is controversial. The aim of this study was to investigate the plasma levels of circulating E- and P-selectin molecules in patients with syndrome X. The study included 21 patients with cardiac syndrome X (11 men and 10 women, mean age = 56 +/- 5 years) and 20 patients with significant coronary artery disease who had stable angina pectoris (11 men and 9 women, mean age = 60 +/- 8 years). Twenty-two age- and sex-matched subjects (12 men and 10 women, mean age = 58 +/- 8 years) undergoing diagnosis of atypical chest pain in whom coronary arteries were found normal and exercise test had no signs of ischemia served as the control group. Syndrome X was defined as presence of typical chest pain on exertion or at rest with positive exercise test and angiographically normal epicardial coronary arteries with no evidence of coronary spasm after intracoronary infusion of ergonovine maleate. The mean plasma concentrations of P-selectin were significantly elevated both in patients with coronary artery disease and syndrome X as compared with control subjects (49.15 +/-7.47 and 42.80 +/- 8.93 vs 22.63 +/-6.47 ng/mL, p < 0.001). Similarly, both patients with coronary artery disease and syndrome X had higher plasma concentrations of E-selectin than the control group (78.85 +/- 16.69 and 68.38 +/- 15.30 vs 36.43 +/- 4.72 ng/mL, p < 0.001). In conclusion, patients with syndrome X had increased plasma concentrations of soluble adhesion molecules, E-selectin and P-selectin, reflecting an ongoing chronic inflammation involved with endothelial dysfunction and enhanced platelet activation/damage in this setting.     

Chinese Adults Are Less Susceptible Than Whites to Age-Related Endothelial Dysfunction

Objectives. We sought to assess the effects of aging on the endothelial physiology of a group of Chinese adults.Background. Several studies have documented an association between aging and progressive arterial endothelial dysfunction in white subjects. We hypothesized that age-related endothelial dysfunction, an important event in atherosclerosis, might be less marked in southern Chinese subjects, in whom the prevalence of coronary heart disease is only ∼20% of that in industrialized countries.Methods. We studied endothelial function in 76 healthy adults aged 16 to 70 years: 38 Chinese from a village of 3,000 people in southern China and 38 white subjects from Sydney, Australia. In each ethnic group, there were 19 younger persons (16 to 40 years) and 19 older adults (55 to 70 years). None had evidence of diabetes, hypertension or clinical vascular disease or had ever been regular cigarette smokers. With the use of high resolution external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilation) and after sublingual nitroglycerin (an endothelium-independent dilator).Results. Endothelium-dependent dilation was similar in young Chinese (mean ± SD 8.3 ± 2.5%), young whites (7.9 ± 2.0%) and older Chinese (6.8 ± 2.9%), but it was significantly impaired in older whites (1.8 ± 2.5%, p < 0.001 by analysis of variance). On multivariate analysis, older age was associated with impaired endothelium-dependent dilation (p < 0.001) (independent of the effects of serum cholesterol, gender and vessel size) in the white but not in the Chinese subjects (p = 0.83). Nitroglycerin-induced dilation was not significantly different with aging in either ethnic group.Conclusions. Endothelium-dependent dilation is similar in the arteries of healthy young Chinese and white adults. With older age, however, Chinese subjects are less susceptible to impaired endothelial function.(J Am Coll Cardiol 1997;30:113–8)