苯那普利对老年高血压病患者血管内皮功能的影响

目的　探讨苯那普利对老年高血压血管内皮功能的影响。方法　采用放射免疫法测定 32例老年高血压患者服用苯那普利前后血管内皮功能的影响变化。结果　治疗前 ET水平升高 ,NO水平降低 ,与对照相比有显著性差异 (P<0 .0 1 )。治疗后 ET水平降低 ,NO水平升高 ,治疗前后比较有显著的差异性。结论　苯那普利可降低 ET,升高 NO,从而改善血管内皮功能。     

老年高血压患者脉压与心功能和血管内皮生长因子及高敏C反应蛋白的关系

目的探讨药物常规治疗下老年高血压患者脉压(PP)与心功能、血管内皮生长因子(VEGF)及高敏C反应蛋白(hs-CRP)的关系。方法将336例老年高血压患者,依据PP水平,分为≤48、49~58、59~68、>68 mm Hg(1 mm Hg=0.133 kPa)4个组,用logistic回归分析各组PP与心功能、VEGF及hs-CRP的相关性。结果随着PP逐渐增大,血清VEGF和hs-CRP水平均明显增高(P<0.01),左心室收缩及舒张功能均明显降低(P<0.05,P<0.01)。logistic回归分析显示,PP与老年高血压患者左心功能不全发生存在明显的相关性。结论老年高血压患者中,PP与VEGF及hs-CRP具有一定的关系,PP是左心功能不全发生的一个重要和独立的相关因素。     

Impaired endothelial function in hypertensive elderly patients evaluated by high resolution ultrasonography.

BACKGROUND: Multiple investigations both in experimental models and in middle-aged patients with essential hypertension have demonstrated impaired endothelium-dependent vasodilation. OBJECTIVE: To determine whether hypertension exerts an additional negative effect on endothelial function of large arteries in hypertensive elderly patients who may already be affected by endothelial dysfunction due to aging. PATIENTS AND METHODS: Thirteen elderly patients with hypertension (69 9 years of age [mean SD]) were compared with 13 matched healthy elderly subjects (72 6 years of age). High resolution vascular ultrasound was used to measure brachial artery responses to reactive hyperemia (with increased flow causing endothelium-dependent dilation) and to sublingual nitroglycerine (causing endothelium-independent dilation). RESULTS: Flow-mediated diameter (FMD) was significantly impaired in the hypertensive elderly group (6.7 3.3% versus 13.3 3.8% in the control group, P<0.05). No significant difference could be found in nitroglycerine-induced dilation between the elderly control group (12.1 4.9%) and the hypertensive elderly (10.2 6.8%). On simple linear analysis, FMD was inversely correlated with age (r=-0.60, P=0. 03) in the healthy elderly group. FMD in the hypertensive elderly was inversely related to age (r=-0.41, P=0.04) and mean blood pressure (r=-0.67, P=0.01). CONCLUSIONS: This study showed decreased FMD with aging even in the healthy elderly, with a further decline in hypertensive elderly compared with healthy elderly subjects. This impairment of FMD in the hypertensive elderly group was related to age and mean blood pressure, indicating that aging and hypertension may impair endothelial function in the brachial artery of elderly patients with hypertension.     

COPD患者血管内皮舒张功能的研究

目的探讨吸烟健康中老年人与慢性阻塞肺病（COPD）患者血管内皮舒张功能水平变化。方法采用高分辨超声检测肱动脉基础动脉内径（DO）、内皮依赖性血流介导的舒张功能（FMD）、非内皮依赖性硝酸甘油介导的舒张功能（NID）,观察正常吸烟对照者、慢性阻塞性肺病及正常不吸烟对照者共78名血流介导的和硝酸甘油介导的肱动脉内径变化。结果COPD组及吸烟健康对照组人群FMD值较正常不吸烟对照组减低（P〈0．05）,同时,COPD组随着疾病分级加重,FMD值亦逐渐减低（P〈0．05）。吸烟、不吸烟对照组及轻度COPD组的NID值统计学无显著性差异（P〉0．05）,而中度至极重度COPD组随肺功能逐渐减退,NID值亦逐渐减低（P〈0．05）,与对照组比较更有显著统计学意义（P〈0．01）。结论吸烟及COPD早期即出现血管内皮功能紊乱,并随疾病进展更趋严重。     

Effects of low‐dose aspirin on endothelial function in hypertensive patients

Background: It has been reported that administration of low‐dose aspirin significantly reduces the frequency of major cardiovascular events in patients with hypertension and coronary artery disease. It is generally considered that the preventative effects of long‐term aspirin administration on major cardiovascular events are due to the inhibition of platelet aggregation. Hypothesis: It is not known whether administration of low‐dose aspirin restores endothelium‐dependent vasodilatation, and this study was undertaken to prove or disprove this question in patients with hypertension. Methods: Flow‐mediated endothelium‐dependent dilatation and glyceryl trinitrate‐induced endothelium‐independent dilatation were investigated in 18 hypertensive patients and 10 normotensive control subjects. In the hypertensive patients, flow‐mediated dilatation was investigated and cyclic guano‐sine monophosphate plasma (cGMP) was measured before and at 8 weeks after the administration of 162 mg of aspirin. Results: Flow‐mediated dilatation before aspirin administration was more reduced in the hypertensive patients than in the control subjects (6.4 ± 2.0% vs. 11.3 ± 2.3%, p< 0.0001). Glyceryl trinitrate‐induced dilatation before aspirin administration was similar in hypertensive patients and control subjects. Flow‐mediated dilatation after aspirin administration was improved compared with that before aspirin administration (10.4 ± 3.5% vs. 6.4 ± 2.0%, p<0.0004). The cGMP product after aspirin administration was significantly higher than that before aspirin administration. Conclusions: Administration of low‐dose aspirin may restore the endothelium‐dependent vasodilatation in hypertensive patients. Furthermore, increased nitric oxide production may play a partial role in the improvement in endothelial function induced by administration of low‐dose aspirin.     

Effects of cyclooxygenase inhibition on endothelial function in hypertensive patients treated with angiotensin-converting enzyme inhibitors

BACKGROUND: Cyclooxygenase inhibition restores endothelium-dependent vasodilatation in hypertension, but it is unknown whether it restores endothelial function in hypertensive patients treated with angiotensin-converting enzyme (ACE) inhibitors. HYPOTHESIS: The purpose of the present study was to evaluate the effects of cyclooxygenase inhibition on endothelial function in hypertensive patients treated with ACE inhibitors. METHODS: Endothelium-dependent flow-mediated dilatation (FMD) and endothelium-independent glyceryl trinitrate-induced dilatation were investigated in 10 patients treated with enalapril (ACE group), 11 patients treated with manidipine and metoprolol (non-ACE group), and 12 normotensive control subjects. After administration of 1000 mg of aspirin, FMD was investigated once again. Plasma cyclic guanosine monophosphate (cGMP) and eicosanoids were also measured during reactive hyperemia before and after aspirin administration. RESULTS: Flow-mediated dilatation was more impaired in the non-ACE group than in the ACE group (8.3 +/- 3.8%, 5.7 +/- 1.7%, respectively, p<0.04). Glyceryl trinitrate-induced dilatation was similar in the ACE group, the non-ACE group, and in the control subjects. In the ACE group, FMD was reduced after administration of aspirin (5.3 +/- 4.2%, p<0.05). The percent change in FMD after administration of aspirin correlated significantly with percent change in cGMP (r=0.77, p<0.03; y-intercept, -62.1%, p<0.01). After aspirin administration, levels of thromboxane B2 and 6-keto-prostaglandin(1alpha) were significantly decreased compared with those before aspirin administration in all groups. CONCLUSIONS: Cyclooxygenase inhibition may reduce the beneficial effect on endothelium-dependent vasodilatation induced by ACE inhibitors. The results suggested that prostacyclin in addition to nitric oxide plays a significant role in the restoration of endothelial function in hypertensive patients treated with ACE inhibitors.     

福辛普利对老年高血压患者内皮依赖性血管舒张功能的影响

目的探讨福辛普利对老年高血压患者内皮依赖性血管舒张功能(FMD)的影响及机制。方法应用高频彩色多普勒超声检测仪对68例老年高血压患者进行FMD的无创检查,并观察福辛普利治疗前后患者FMD的变化。结果福辛普利治疗后老年高血压患者血管内径和硝酸甘油诱发的肱动脉内径变化率与治疗前无明显差异(P>0.05),但反应性充血诱发的肱动脉内径变化率较治疗前明显增加(P<0.05)。结论老年高血压患者出现明显FMD障碍,福辛普利治疗可改善老年高血压患者血管内皮功能。     

氯沙坦对高血压病患者血管内皮功能的影响及其临床意义

目的探讨氯沙坦对高血压病患者血管内皮功能的影响及其临床意义。方法采用血浆内皮素（ET）,一氧化氮（NO）,血小板α-颗粒膜蛋白（GMP140）和血管性假血友病因子（vWF）水平作为内皮功能指标,观察45例高血压病患者氯沙坦治疗4周前后血管内皮功能的改变。结果高血压组治疗前血浆ET、vWF和GMP140均显著高于正常对照组,NO/ET较正常对照显著降低（P<0.05,P<0.01）。治疗4周,高血压组的血浆ET、vWF、GMP140较前显著降低（P<0.05,P<0.01）。血浆NO及NO/ET较前显著升高,并且NO显著高于正常对照组（P<0.05,P<0.01）。ET与血总胆固醇（TC）、SBP正相关,NO和NO/ET与空腹血糖、SBP和三酰甘油显著负相关,NO/ET还与HDL正相关,vWF、GMP140与HDL负相关,GMP140与TC正相关（P<0.05,P<0.01）。结论高血压患者存在血管内皮功能减退,内皮功能与收缩压、血糖、血脂相关联。氯沙坦能够改善高血压患者的血管内皮功能。     

Effects of nebivolol versus bisoprolol on endothelial function in hypertensive patients

OBJECTIVE:

To determine the effects of two beta-blockers, nebivolol and bisoprolol, on endothelial function in newly diagnosed hypertensive patients.

METHODS:

Twenty-five hypertensive patients with a mean (± SD) age of 45.3±11.5 years were randomly assigned to receive either nebivolol or bisoprolol for eight weeks in an open-label, crossover design. Flow-mediated endothelial-dependent vasodilation (FMD) was measured at baseline and after each eight-week treatment period. At the end of each treatment period, 24 h ambulatory blood pressure (BP) monitoring was performed.

RESULTS:

The effect of the two beta-blockers on BP was similar. The mean FMD before initiation of treatment was 4.14±3.55%. After treatment with nebivolol, FMD increased to 8.99±4.21%, with a statistically significant difference from baseline (P<0.001). The effect of bisoprolol treatment on FMD was not as dramatic (3.72±6.84%), with no statistically significant difference from baseline. Comparing FMD after each therapeutic regimen, nebivolol treatment resulted in a marked increase in the reactivity of the brachial artery (ie, improvement of endothelial function) compared with bisoprolol treatment (P<0.001).

CONCLUSION:

Nebivolol treatment of untreated hypertensive patients led to a significant improvement in endothelial function compared with bisoprolol treatment, despite the similar effect on BP with either therapeutic agent.     

A new noninvasive method for evaluation of coronary endothelial function in hypertensive patients based on change in diameter of the left main coronary artery induced by cold pressor test using echocardiography

BACKGROUND: Coronary endothelial function is frequently studied by measuring the vasodilator response of coronary arteries to acetylcholine or to cold pressor test by invasive quantitative coronary angiography. Because invasive methods have substantial inherent limitations, studies should attempt to evaluate coronary endothelial function noninvasively. HYPOTHESIS: We attempted to evaluate the accuracy of measurement of the percent change in diameter of the left main trunk induced by cold pressor test with two-dimensional (2-D) echocardiography. Furthermore, we applied this method to the evaluation of coronary artery endothelial function in hypertensive patients. METHODS: We measured the left main trunk diameter in 21 subjects (51 +/- 4 years) before and after cold pressor test using quantitative coronary angiography followed immediately by 2-D echocardiography. The accuracy of measurement of the left main trunk diameter and its percent change by echocardiography was evaluated by comparing the values obtained by the two methods. In addition, using echocardiography, we compared left main trunk diameter responses to cold pressor test in 16 hypertensive patients [51 +/- 5 years (mean +/- standard deviation)] and 16 matched healthy subjects (50 +/- 4 years). RESULTS: Although there was only a weak correlation between the absolute values of the left main trunk diameter measured by the two methods (r = 0.61; p = 0.04), a strong correlation was found between the percent change in diameter measured by the two methods (r = 0.93; p = 0.0001). The percent change in diameter of the left main trunk induced by cold pressor test in hypertensive patients (-3.7 +/- 10.6%) was significantly lower than that in control subjects (13.2 +/- 6.8%, p = 0.0001). CONCLUSIONS: Percent change in diameter of the left main trunk induced by cold pressor test can be evaluated accurately using 2-D echocardiography. Our study showed reduced vasodilation or vasoconstriction of the left main trunk after cold pressor test in hypertensive patients compared with healthy subjects, indicating impaired coronary endothelial function in hypertensive patients. The present echocardiographic method is a potentially useful new noninvasive method for evaluating coronary endothelial function.     

Non-invasive evaluation of endothelial function in hypertensive elderly patients

Impaired endothelium-dependent vasomotion is a diffuse disease process resulting in abnormal regulation of blood vessel tone and loss of several atheroprotective effects of the normal endothelium. The aim of the present study was to investigate the effects of aging and hypertension on endothelial function. Sixty-six geriatric subjects with ages over 60 (48 hypertensive and 18 healthy) and 40 middle-aged subjects (16 hypertensive and 24 healthy) were included in the study. Systemic vascular endothelial function was evaluated through measuring brachial arterial vasodilation, a physiologic answer to reactive hyperemia occured with increased blood flow in the vessel after transient ischemia (flow-mediated dilation, FMD%), and with carotid artery intima-media thickness (IMT) measurement, using high-resolution ultrasonography. Endothelial independent vasodilation was also measured after administration of sublingual isosorbide dinitrate (isosorbide dinitrate mediated dilation, IDNMD%). FMD% was significantly decreased in elderly and/or hypertensive (HT) patients (geriatric HT: 9.5 +/- 4.7%, geriatric non-HT: 12.7 +/- 5.5%, middle-aged HT: 12.9 +/- 4.3% and middle-aged non-HT: 18.9 +/- 8.1%) (geriatric HT versus geriatric non-HT (P = 0.02), geriatric HT versus middle-aged HT (P = 0.01), geriatric non-HT versus middle-aged non-HT (P = 0.008)). Both FMD% and IDNMD% were inversely correlated with age, baseline vessel diameter and carotid artery intima-media thickness. FMD% was also inversely correlated with diastolic blood pressure. No correlation was found between FMD% and systolic blood pressure, serum cholesterol and triglyceride levels. Endothelium dependent (EDD) and independent dilatation of large arteries decreased with aging even in the healthy elderly, and FMD further declined in HT elderly patients, indicating that age and hypertension independently impair endothelial function. Positive correlations with age and hypertension, and significant inverse correlation with FMD, makes carotid artery IMT a possible indicator of endothelial function.     

冷加压试验超声心动图评价高脂血症患者的冠状动脉内皮功能

目的 :应用冷加压试验超声心动图评价高脂血症患者的冠状动脉内皮功能。方法 :将 80例研究对象对分为两组 :高脂血症组、正常对照组。高脂血症组又分为高胆固醇血症、高三酰甘油血症和混合性高脂血症三个亚组。应用超声心动图仪显示静息状态下、冷加压负荷试验后、舌下含服硝酸甘油后的冠状动脉左主干图像 ,测量其内径并计算内径变化百分率。结果 :与正常对照者相比 ,高脂血症患者冷加压负荷试验前后冠状动脉左主干内径变化百分率明显降低 [(15 .6± 6 .0 ) %∶(9.8± 3.5 ) %、(9.9± 3.5 ) %、(8.0± 3.4 ) % ,均P <0 .0 5 ],其中又以混合性高脂血症者为甚。结论 :冷加压试验超声心动图可用于检测冠状动脉内皮功能 ;高脂血症患者冠状动脉内皮功能异常。     

Valsartan and retinal endothelial function in elderly hypertensive patients

BACKGROUND: The aim of this study was to investigate the impact of short-term treatment with the angiotensin II receptor blocker (ARB) valsartan on retinal endothelial function in elderly patients with mild to moderate essential hypertension. METHODS: In an open-labeled study, 20 elderly, male patients with arterial hypertension (WHO I-II) were treated with the ARB valsartan (80-160 mg once daily) over 8 days. Central retinal artery perfusion at rest and during flicker light stimulation was measured before and after treatment using pulsed wave Doppler sonography. Retinal capillary flow was assessed with scanning laser Doppler flowmetry at rest and following systemic infusion of the nitric oxide synthase (NOS) inhibitor NG-monomethyl-L-arginine (L-NMMA). RESULTS: While valsartan significantly lowered blood pressure, central retinal artery perfusion at rest as well as after flicker light stimulation was similar before and after treatment. Similarly, retinal capillary flow at rest and after infusion of L-NMMA did not change with valsartan after 7 days of treatment. Subgroup analysis revealed that changes in retinal capillary flow in response to L-NMMA might be dependent on serum low-density lipoprotein (LDL) cholesterol levels of study participants. After treatment with valsartan, retinal capillary flow in response to L-NMMA decreased more in patients with low (< 3.54 mmol/l) than with high LDL-cholesterol levels (-12.6 +/- 20.2% vs 12.3 +/- 19.5%, p < 0.05). CONCLUSION: Short-term treatment with valsartan did not improve retinal endothelial function in elderly hypertensive patients.     

Impaired endothelial function in patients with myocardial bridge

OBJECTIVE: The relationship between myocardial bridging (MB) and ischemic heart disease is still controversial. In this study, we aimed to evaluate the existing atherosclerosis and noninvasive endothelial function of brachial artery in patients with MB. METHODS: The present study included 50 patients (group I) who had MB in left anterior descending (LAD) on coronary angiography. All of the coronary artery segments were evaluated by intravascular ultrasound (IVUS). Endothelial function was assessed with measurement of flow-mediated dilatation (FMD) and nitrate-dependent dilatation in the brachial artery. The study also included 30 healthy control subjects (group II). Patients in the group I were further subdivided into two subgroups based on the findings on IVUS: group IA included 20 patients without atherosclerotic lesions and group IB included 30 patients with atherosclerotic coronary artery disease in addition to MB. RESULTS: FMD values were found to be significantly lower in the patients with MB (group I) than in the control (6.4 +/- 3% vs 11 +/- 4%, P <0.001). In regard to FMD values in subgroups, FMD was 7 +/- 2% in the group IA and 5.8 +/- 1% in the group IB (P = 0.023). On IVUS, atherosclerotic plaque was found proximal to the bridge in the same coronary artery segment in addition to MB in 75% of the patients in group I (group IB). No atherosclerotic plaque was found in within or distal segments of MB. CONCLUSION: Endothelial function is impaired in patients with MB and there is an increased tendency for atherosclerosis proximal to the bridge in the patients with MB. Endothelial dysfunction is more severe in the patients with atherosclerosis proximal to the bridge.     

高频超声评价高血压患者血管内皮功能的研究

目的:探讨高血压对血管内皮功能的影响。方法:应用高频超声检测48例原发性高血压患者和45例血压正常的健康人在静息状态、反应性充血后以及舌下含服硝酸甘油后的肱动脉内径变化。结果:原发性高血压患者反应性充血引起肱动脉内径扩张显著低于血压正常的健康人(7.62%±5.10%)vs(14.53%±3.82%),P<0.01,舌下含服硝酸甘油引起肱动脉内径扩张差异无统计学意义(18.23%±3.20%)vs(18.87%±4.35%),P>0.05。结论:原发性高血压患者存在血管内皮依赖性舒张功能受损,高频超声可以是评价血管内皮功能的无创、简单、可靠的方法。     

组织多普勒成像技术评价老年高血压患者右心室功能的临床研究

目的探讨组织多普勒成像(TDI)技术评价老年高血压患者右心室功能的临床价值。方法选择老年高血压患者34例(高血压组)和健康老年人44例(对照组)。经胸超声心动图检查,应用TDI技术于心尖四腔观获取右心室侧壁三尖瓣环处心肌运动频谱图,测量舒张早期峰值速度(Em)、舒张晚期峰值速度(Am),并计算Em和Am比值。同时测量收缩期峰值速度(Sm)、等容收缩期心肌加速度。结果高血压组Em(5.91±1.56)cm/s、Am(12.79±2.63)cm/s、Sm(10.82±1.45)cm/s均明显低于对照组Em(7.57±2.11)cm/s、Am(14.27±2.03)cm/s、Sm(12.68±2.33)cm/s,差异有统计学意义(P=0.000,P=0.006,P=0.000);Em/Am高血压组(0.47±0.12)明显低于对照组(0.54±0.15),差异有统计学意义(P=0.048)。结论 TDI可以准确、直观地评价老年高血压患者右心室功能。     

富钾盐对高血压患者血压、内皮功能影响及安全性评价

目的观察富钾盐（氯化钠、氯化钾各占50%）对高血压患者血压、内皮功能的影响及安全性。方法纳入河北省清河县某农村自愿参加富钾盐试验的198户家庭,采用单盲的方法,随机将纳入家庭分入普通盐组（氯化钠〉99%）和富钾盐组（氯化钠、氯化钾各占50%）。采用统一调查问卷,对受试人群进行基线调查。在进行1年的膳食盐的干预后,从高血压患者中随机抽取资料完整的患者93例（普通盐组46例,富钾盐组47例）。测定与比较两组高血压患者干预前、后血压水平,干预后的血清一氧化氮（NO）和内皮素-1（ET-1）水平,胱抑素C（CysC）和尿微量白蛋白/肌酐（mAlb/Cr）水平等指标的变化。结果改变膳食钠、钾含量后,富钾盐组血压较基线时下降7.9/3.6mmHg,具有统计学差异（P〈0.05）;普通盐组干预前、后血压无统计学差异（P〉0.05）;干预前、后两组患者血压均无统计学差异（P〉0.05）;干预后两组患者血清NO及ET-1水平,均有统计学差异（P〈0.05）;两组血清CysC水平及mAlb/Cr值比较,均无统计学差异（P〉0.05）。两组患者血钾均在正常值范围。结论食用富钾盐具有降低高血压患者血压水平趋势、保护血管内皮功能,且具有良好的安全性。     

氯沙坦对糖尿病合并原发性高血压患者内皮细胞功能的影响

目的观察血管紧张素Ⅱ受体拮抗剂氯沙坦对糖尿病合并高血压患者内皮细胞功能及其分泌因子的影响。方法入选48例糖尿病合并1～2级高血压患者,给予氯沙坦50mg／d治疗4周,如血压未得到控制[收缩压≥140mmHg和（或）舒张压≥90mmHg],将药物剂量加倍继续治疗4周。采取静脉血测定治疗前、后血浆降钙素基因相关肽（CGRP）、一氧化氮（NO）、前列环素（PGI2）、内皮素（ET）、血管紧张素Ⅱ（AngⅡ）水平及血压的变化。结果31例治疗2周末血压降至正常,收缩压（162．3±23．8）mmHg比（131．5±17．3）mmHg（P〈0．05）,舒张压（106．4±14．9）mmHg比（85．3±13．5）mmHg（P〈0．01）,其后血压稳定。治疗4周后血浆CGRP和PGI2显著升高,分别为（117．3±19．5）ng／L比（164．2±23．1）ng／L（P〈0．01）和（116．6±69．1）pg／ml比（223．5±84．9）pg／ml（P〈0．01）;血浆AngⅡ水平显著降低[（539．8±226．2）pg／ml比（441．3±161．1）pg／ml,P〈0．05]。其余17例治疗4周后,因收缩压或舒张压未降至正常水平,药量加倍再治疗4周,血压显著下降,收缩压（167．2±21．7）mmHg比（144．2±13．5）mmHg,P〈0．05,舒张压（112．7±13．7）mmHg比（96.3±12．1）mmHg,P〈0．01;血浆CGRP水平显著升高[（112．7±13．7）ng／L比（171．6±37．1）ng／L,P〈0．05],和健康人水平[（178．1±34．7）ng／L]差异无统计学意义（P〉0．05）。结论氯沙坦是一种安全有效的降压药物,同时可以改善糖尿病合并高血压患者血管内皮细胞功能。     

高同型半胱氨酸血症诱导eNOS脱偶联损害冠状动脉内皮功能

目的探讨高同型半胱氨酸血症（HHcy）患者冠状动脉内皮功能是否被损伤,以及这种损伤是否通过内皮型一氧化氮合酶（eNOS）脱偶联实现的。方法 71例参与者被分成健康对照组（n=50）和HHcy组（n=21）,利用多普勒超声心动测定腺苷诱导下冠状动脉左前降支的舒张功能的改变,冠脉血流速度储备（CFVR）由最大血流速度与基线水平的比值计算得出。采用ELISA以及高效液相色谱法测定血浆一氧化氮（NO）、四氢生物蝶呤（BH4）的水平。结果与健康对照组相比,HHcy组患者血浆NO、BH4的水平降低（P〈0.05）;HHcy组CFVR低于健康对照组（P〈0.05）;血浆Hcy水平与NO及CFVR呈负相关（P〈0.05）。结论 HHcy可能通过降低BH4生物利用度,诱导eNOS脱偶联,而导致冠状动脉内皮功能损伤,进而促进不良冠脉事件的发生。