The predictive value of flow-mediated dilation and carotid artery intima-media thickness for occult coronary artery disease

Background: Multidetector row computed tomography (MDCT) is an attractive noninvasive alternative to assess overall coronary artery disease (CAD) burden and may reveal coronary plaques, which may be underestimated by conventional coronary angiography. The aim of this study was to determine whether brachial artery flow‐mediated dilation (FMD) and carotid artery intima‐media thickness (CIMT) might accurately predict patients with occult coronary plaques whose conventional coronary angiographies revealed normal coronary arteries (NCA). Methods: Thirty‐five patients with angiographically NCA were consecutively recruited into the study. They underwent MDCT and were divided into NCA group (18 patients; 8 male; 47 ± 9 years) and occult CAD group (17 patients; 11 male; 50 ± 10 years) according to presence of coronary plaque. Nineteen consecutive patients with evident CAD (16 male; 54 ± 7 years) and 19 healthy subjects (10 male; 50 ± 6 years) were included as control groups. FMD and CIMT were measured by brachial and carotid artery ultrasonography. Results: Occult CAD group had significantly lower FMD and insignificantly higher CIMT than NCA group whereas they had significantly higher FMD and insignificantly lower CIMT than evident CAD group. NCA group had significantly lower CIMT than evident CAD group. Receiver operating characteristic curve analysis demonstrated FMD < 8% (sensitivity: 94.4%; specificity: 73.0%; PPV: 77.3%; NPV: 93.1%) and CIMT ≥ 0.65 cm (sensitivity: 72.2%; specificity: 62.2%; PPV: 65.0%; NPV: 69.7%) could predict patients with CAD. FMD and CIMT were independent predictors of CAD (P < 0.001; OR: 45.630; 95%CI: 5.38–386.983 and P = 0.015; OR: 14.226; 95%CI: 1.666–121.467, respectively). Conclusion: FMD and CIMT might predict patients with occult CAD and be helpful in selecting patients for MDCT. (Echocardiography 2011;28:1141‐1147)     

颈动脉内中膜厚度与冠心病的关系分析

目的：通过颈动脉内-中膜厚度（IMT）的测定,分析颈动脉粥样硬化与冠心病的关系。方法：对158例接受脉造影的患者行颈动脉IMT及斑块超声检查,比较有无冠脉病变及不同程度冠脉病变与颈动脉IMT的关系。结果：无冠心病者50例,冠心病单支病变组53例,多支病变组55例。冠心病患者的颈动脉IMT[单支病变（0．91±0．1）mm）,多支病变（1．08±0．15）min]分别明显高于非冠心病者[（0．83±0．08）mm,P均〈0．057,冠心病患者的斑块检出率[单支病变52．6％,多支病变65．7％]分别明显高于非冠心病者的32％（P均〈0．05）。多支冠状动脉病变组的颈动脉IMT及斑块检出率明显高于单支冠状动脉病变组（P均〈0．05）。结论：颈动脉粥样硬化对冠心病有一定的预测价值,颈动脉IMT可作为间接反映冠状动脉病变程度的指标。     

Carotid artery intima-media thickness is associated with coronary artery disease

OBJECTIVE: The intima-media thickness (IMT) of the carotid artery is dependent on the risk factor load during life and correlates well with the degree of atherosclerosis, also in other vascular beds. METHODS: We reviewed our database of IMT measurements, from January 2002 to February 2007. We compared the mean IMT values of patients without a history of coronary artery disease (group 1) with those with a history of coronary artery disease (group 2). For both groups we divided the results of measurements according to age. We compared the IMT between both groups and looked for a correlation with increasing age. The IMT was measured with high-resolution echography at the posterior wall of the common carotid artery, using an automated edge-tracking method. RESULTS: The database contained 598 IMT measurements in group 1 and 672 in group 2. In both groups we observed a significant increase in IMT with increasing age. Within a certain age group, a significant difference in IMT between group 1 and 2 occurred at an age of 40 years or above (age 40-65: IMT 645.54 versus 671.71 microm, respectively, P = 0.04, and age > 65 years: IMT 715.2 versus 772.91 microm, respectively, P = 0.01). CONCLUSIONS: IMT increases with age and is higher in patients with a history of vascular disease. This difference is significant in patients of 40 years or older. This finding supports the recommendations of the prevention conference of the American Heart Association, that carefully performed IMT measurement can add incremental information to traditional risk factor assessment in asymptomatic individuals above the age of 45 years.     

The carotid intima-media thickness as a marker of the presence of severe symptomatic coronary artery disease

High resolution ultrasound can be used for the accurate measurementof intima-media thickness (IMT). The within-observer coefficientof variation of the IMT of two carotids measured seven timeseach on different days by two different observers was between4% and 8%, and the mean absolute difference of the IMT of 68carotids measured independently by two observers was 0.11 ±0.11 mm (mean value ± SD). Seventy-five consecutive male patients who underwent coronaryangiography for assessment of chest pain and 40 normal controlsmatched for age and sex, were examined with high resolutionB-mode ultrasound. The IMT of the common carotid artery forthe controls was 0.71 ± 0.16 mm and for the patients0.91 ± 0.18 mm (P<0.005). In patients with normalcoronary angiogram the IMT was 0.73 ± 0.1 mm, and thisincreased in each of the subgroups with coronary stenosis comparedto patients who had a normal coronary angiogram. In the groupwith one-vessel disease it was 0.9± 0.17 mm (P<005,ANOVA), in the group with two-vessel disease it was 0.96 ±0.17 mm (P<0.01), and in the group with three-vessel diseaseit was 0.99 ± 0.21 mm (P<0.01). There was a significantlinear trend between IMT and the number of involved vessels(P<0.0001, r=0.44). An IMT>0.85 mm was derived from thestudied population of 75 patients as a criterion for the predictionof coronary artery disease (CAD). This criterion was prospectivelyevaluated in a further group of 32 consecutive patients, inwhom it could predict the presence of CAD with a specificityof 77%, a sensitivity of 43% and a positive predictive valueof 83%. Thus, an increased carotid IMT is a marker of coronary vasculardisease which can be measured non-invasively and may be usedas a biological marker of CAD in observational studies and clinicaltrials. In addition, an increased IMT may have considerableimportance as a screening tool for coronary atheroma.     

心外膜脂肪组织及颈动脉内中膜厚度与冠心病的相关性研究

目的评价经高频超声测量的心外膜脂肪组织厚度(epicardial adipose tissue,EAT)和颈动脉内中膜厚度(intima-media thickness,IMT)对冠状动脉狭窄程度的预测价值。方法 92例接受冠状动脉血管内超声检查的患者,根据结果分为非冠心病(coronary artery disease,CAD)组25例和CAD组67例,CAD组依据病变程度分为轻、中、重三亚组;经超声测量EAT和IMT,对各组之间的EAT值和颈动脉IMT进行比较,将EAT和颈动脉IMT与CAD进行相关性分析。结果 CAD组与非CAD组比较,EAT和颈动脉IMT值明显升高[(6.54±1.21)mmvs.(4.98±1.33)mm,P<0.05;(1.02±0.20)mm vs.(0.83±0.18)mm,P<0.05];CAD三亚组之间随着病变程度的加重,EAT和颈动脉IMT值逐渐升高。直线相关分析显示EAT(r=0.624,P<0.001)及颈动脉IMT(r=0.392,P<0.001)与冠状动脉面积狭窄率呈直线正相关,Logistic回归分析表明EAT和颈动脉IMT均是CAD的独立危险因子,P值分别是0.028和0.032(P<0.05)。以EAT值≥5.16 mm诊断CAD,诊断敏感性83.6%,特异性68.0%,受试者工作曲线下面积为82.2%(P=0.001);以颈动脉IMT≥0.87 mm预测CAD的敏感性77.6%,特异性64.0%,受试者工作曲线下面积为76.6%(P=0.001)。结论经超声测量EAT和颈动脉IMT可作为评价冠状动脉病变程度简便、可靠和实用的评价指标,可作为CAD患者无创的协同诊断方法。     

Carotid intima-media thickness and coronary artery disease: an Indian perspective

To determine whether carotid intima-media thickness is associated with coronary artery disease and cardiovascular risk factors in the Indian population, carotid intima-media thickness was measured using high-resolution B-mode ultrasonography in 101 patients with coronary artery disease and 140 control subjects. Carotid intima-media thickness was measured at 3 predefined sites on each side. The maximum carotid intima-media thickness was significantly higher in the coronary disease group compared to the controls (1.02 vs. 0.80 mm). The average intima-media thickness was also significantly higher in the coronary disease group (0.82 vs. 0.67 mm). On multivariate logistic regression analysis, carotid intima-media thickness was the only factor found to be an independent predictor of coronary artery disease. There was a significant association between risk factor count and the average and maximum intima-media thickness values in the combined study population. These results indicate that raised values of average and maximum carotid intima-media thickness are significantly associated with the presence of coronary artery disease and this association is independent of the presence of other conventional cardiovascular risk factors.     

Usefulness of flow-mediated dilation of the brachial artery and/or the intima-media thickness of the carotid artery in predicting coronary narrowing in patients suspected of having coronary artery disease.

It has been reported that flow-mediated dilation (FMD) of the brachial artery and the carotid intima-media thickness (IMT), markers of atherosclerosis, are altered in patients with coronary artery disease (CAD), but it is still not known if the presence of CAD can be detected using these markers. We examined whether the presence of CAD can be detected by FMD of the brachial artery and/or IMT. Eighty-one patients who underwent coronary angiography for the first time were enrolled. In each patient, brachial artery diameter responses to FMD and the administration of nitroglycerin spray, and carotid IMT were measured using high-resolution ultrasound (10 MHz) before coronary angiography. CAD was defined as >50% stenosis of a major coronary artery. Fifty-six patients had CAD. FMD was lower and IMT was greater in patients with CAD (FMD, 2.9 +/- 0.2% vs 9.4 +/- 0.5%; IMT, 1.09 +/- 0.05 vs 0.79 +/- 0.04 mm, both p <0.0001). Nitroglycerin-induced dilation did not differ in the 2 groups. Multivariate analysis showed that FMD was the only predictor of the presence of CAD (p = 0.0026). Receiver-operating characteristic analysis demonstrated that a cutoff value for FMD for detecting the presence of CAD was 6%, with a sensitivity of 0.93 (52 of 56) and a specificity of 0.88 (22 of 25). These findings suggest that FMD but not IMT may be used to detect the presence of CAD in patients with suspected CAD.     

Relation of brachial artery flow-mediated vasodilation to significant coronary artery disease in patients with peripheral arterial disease

In patients at risk for coronary atherosclerosis, brachial artery flow-mediated dilation (FMD) rules out significant coronary artery disease (CAD). However, the value of this approach is unknown in patients with peripheral arterial disease who are at increased risk for CAD. This study assessed whether the noninvasive evaluation of endothelial function by brachial artery FMD rules out significant CAD by dipyridamole myocardial perfusion imaging (MPI) in patients with peripheral arterial disease who are asymptomatic for CAD. Forty-four patients with peripheral arterial disease who were asymptomatic for CAD underwent, in the same day, FMD evaluation and dipyridamole MPI using technetium-99m sestamibi single photon-emission computed tomography. MPI results were abnormal in 17 of 44 patients (39%). FMD was significantly less (6.0 +/- 2.3%) in patients with abnormal MPI results compared with those with normal MPI results (7.3 +/- 1.8%, p = 0.04). By multivariate analysis, FMD was the only significant predictor of abnormal MPI results (odds ratio 0.63, p = 0.02). Receiver-operating characteristic curve analysis assessing the ability of FMD to identify patients with summed stress scores > or =3 yielded an area under the curve of 0.74 (p = 0.009). A FMD value >6% provided 92% negative predictive power to rule out abnormal MPI results, with sensitivity of 79% and specificity of 73%. In conclusion, the noninvasive evaluation of endothelial function by FMD has high negative predictive accuracy and good sensitivity and specificity to detect abnormal MPI results in patients with peripheral arterial disease. Thus, it may represent a valuable screening test to rule out significant CAD in these patients.     

Gender-based differences in brachial artery flow-mediated vasodilation as an indicator of significant coronary artery disease

Ultrasound of the brachial artery is widely used to assess endothelial function, but whether brachial artery flow-mediated vasodilation (FMD) differs between women and men who have coronary artery disease (CAD) has not been examined. To investigate gender-based differences in brachial artery FMD as an indicator of significant CAD, FMD was measured in women and men outpatients who had CAD (coronary stenosis >50%, n = 64) and those who did not have significant CAD (n = 145). FMD in women who had CAD (n = 33, 9.1 +/- 0.8%) was higher than that in similarly aged men who had CAD (n = 31, 6.4 +/- 0.5%; p = 0.008). The FMD cutpoint that maximized sensitivity with least effect on specificity for screening CAD was 15% (91% sensitivity, 25% specificity) in women but 10% (90% sensitivity, 43% specificity) in men. If the cutpoint as defined in men were used to evaluate women, brachial artery ultrasound would fail to diagnose 42% of women who do not have significant CAD; thus, a higher FMD cutpoint is required to optimize the sensitivity of FMD for identifying women who have significant CAD compared with similarly aged men. In studies using FMD to evaluate cardiovascular risk, different standards should be applied for women and men.     

Diagnostic accuracy of 64-slice multislice computed tomography in the noninvasive evaluation of significant coronary artery disease

The purpose of the present study was to determine the diagnostic accuracy of current 64-slice multislice computed tomography (MSCT) in the detection of significant coronary artery disease, using conventional coronary angiography as the gold standard. In 61 patients scheduled for conventional coronary angiography, 64-slice MSCT was performed and evaluated for the presence of significant (>or=50% luminal narrowing) stenoses. One patient had to be excluded because of a heart rate>90 beats/min during data acquisition. In the remaining 60 patients (46 men, 14 women; average age 60+/-11 years), 854 segments were available for evaluation. Of these segments 842 (99%) were of sufficient image quality. Conventional coronary angiography identified 73 lesions, of which 62 were detected by MSCT. The corresponding sensitivity and specificity were 85% and 97%, respectively. On a patient-per-patient analysis, sensitivity, specificity, and positive and negative predictive values were 94%, 97%, 97%, and 93%, respectively. In conclusion, the present study confirms that 64-slice MSCT enables the accurate and noninvasive evaluation of significant coronary artery stenoses.     

Correlation between flow-mediated vasodilatation of the brachial artery and intima-media thickness in the carotid artery in men

Endothelial dysfunction has been reported to be the initial step in atherosclerosis. A noninvasive technique that uses ultrasound to measure the intima-media thickness of the carotid artery has been applied to evaluate localized atherosclerosis. This study was undertaken to elucidate whether endothelial dysfunction in the brachial artery is related to the intima-media thickness of the carotid artery. Thirty-four men with atherosclerosis (mean+/-SE age 61+/-2 years) and 33 age-matched men without clinical atherosclerosis were examined. The intima-media thickness and plaque formation of the common carotid artery were assessed by B-mode ultrasonography. We also noninvasively measured brachial artery diameter by the same ultrasound machine when the subjects were at rest, during reactive hyperemia, which causes endothelium-dependent vasodilatation, and after sublingual administration of nitroglycerin, which causes endothelium-independent vasodilatation. The atherosclerosis group had a significantly greater intima-media thickness of the common carotid artery than did the control group (1. 02+/-0.04 versus 0.91+/-0.03 mm, P<0.05). The flow-mediated diameter (FMD) increase (percent FMD=DeltaD/D x 100) in the atherosclerosis group was significantly smaller than that in the control group (2. 8+/-0.4% versus 5.1+/-0.6%, P<0.01). A significant negative correlation between the intima-media thickness of the carotid artery and percent FMD was found in all of the subjects. On multiple regression analysis, percent FMD showed a significant negative correlation with the intima-media thickness of the common carotid artery. These findings support the concept that endothelial dysfunction is significantly related to atherogenesis.     

颈动脉内-中膜厚度与冠状动脉粥样硬化性心脏病相关性研究

目的:探讨颈动脉内-中膜厚度在预测冠心病及其程度中的价值.方法:收集361例研究对象的体重、身高、血压、血脂等数据.行颈部血管超声分别测量左右颈总动脉、颈内动脉、颈外动脉和颈动脉分叉的内-中膜厚度.采用标准的Judkins技术行冠状动脉造影.根据造影结果分为正常组、单支病变组、双支病变组、3支病变组共4组.进行颈动脉内-中膜厚度与冠心病的相关性研究.结果:冠心病不同严重程度组中颈动脉不同位点内-中膜厚度值与正常组比较均差异有统计学意义,其冠心病不同严重程度组间颈动脉不同位点内-中膜厚度值比较也均存在统计学差异.颈动脉内-中膜厚度值随冠状动脉病变程度的加重而增厚.左、右颈动脉分叉的特异度、阳性预测值、阴性预测值、准确度、约登指数及阳性似然比最高.年龄、TC、TG、LDL是颈动脉内-中膜的危险因素,而HDL是其保护因素.结论:颈动脉内-中膜厚度与冠心病严重程度明显相关.颈动脉内-中膜厚度可以作为筛选冠心病的指标.     

肱动脉血流介导的舒张功能与冠状动脉病变的关系

目的:观察冠心病(CHS)患者肱动脉血流介导的舒张功能与冠状动脉(冠脉)病变之间的关系。方法:选择冠脉造影(CAG)患者107例,根据cAG结果分为冠脉正常组28例、冠脉早期病变组31例、CHD组48 例,CHD组采用Gensini评分进一步分为轻度病变(1-20分)26例,重度病变(≥20分)22例。在CAG前24 h 内应用高分辨率超声检测肱动脉血流介导的舒张功能,与CAG结果作对照分析。结果:CHD组中轻度病变与重度病变者较冠脉早期病变组及冠脉正常组的肱动脉内皮依赖的舒张功能(EDD)明显降低[(4．75±0．94)％、 (3．67±1．01)％:(5．98±0．89)％、(6．15±0．97)％,P<0．05或0．01];重度冠脉病变者EDD较轻度冠脉病变者明显下降[(3．67±1．01)％:(4．75±0．94)％,P<0．05]。而硝酸甘油介导的血管扩张功能(非EDD)在各组间差异无统计学意义(P>0．05)。肱动脉EDD与冠脉病变积分呈负相关(r=0．72,P<0．01)。结论: CHD患者常存在肱动脉EDD受损,肱动脉EDD可间接反映冠脉病变程度。     

Association between periodontal disease and its treatment,flow-mediated dilatation and carotid intima-media thickness: A systematic review and meta-analysis

Objective

This meta-analysis sought to investigate the association between carotid intima-media thickness (c-IMT), flow-mediated dilation (FMD) and periodontitis (PD) and to assess the effect of periodontal treatment on c-IMT and FMD.

Methods

Electronic database searching, hand searching of bibliographic references of included papers, related reviews, and journals in relation to oral, cardiovascular and ultrasound imaging field was carried out. Random effects meta-analyses were performed to investigate the association of co-existence of increased c-IMT, impaired FMD and PD with potential changes in these variables following periodontal intervention.

Results

2009 citations and 101 full text articles were screened, with 35 meeting the review inclusion criteria of which 22 suitable for quantitative analysis. Meta-analysis demonstrated that the diagnosis of PD was associated with a mean increase in c-IMT of 0.08 mm (95% C.I. = 0.07–0.09) and a mean difference in FMD of 5.1% compared to controls (95% C.I. = 2.08–8.11%). A meta-analysis of the effects of periodontal treatment on FMD showed a mean improvement of 6.64% between test and control (95% C.I. = 2.83–10.44%).

Conclusions

This review demonstrated an association between increased c-IMT, impaired FMD and PD. Data from intervention studies suggested a beneficial effect of periodontal treatment on FMD indicating an improvement in endothelial function. The findings support investigation of periodontitis treatment on cardiovascular outcomes.     

Relationship between carotid artery intima-media thickness and brachial artery flow-mediated dilation in middle-aged healthy men

OBJECTIVES: We aimed to determine the relationship between carotid intima-media thickness (IMT) and brachial artery flow-mediated dilation (FMD) in healthy middle-age men. BACKGROUND: Carotid IMT and brachial artery FMD are frequently used as surrogate measures of subclinical atherosclerosis. Whereas carotid IMT identifies early structural abnormalities, brachial artery FMD, considered a bioassay of endothelial function, measures functional vascular integrity. The relationship between carotid IMT and brachial artery FMD has not been well studied. METHODS: We measured traditional risk factors, carotid IMT, and brachial artery FMD in 1,578 middle-aged men without known cardiovascular disease and analyzed the relationship between carotid IMT and brachial FMD. RESULTS: Carotid IMT correlated with age, systolic blood pressure, body mass index, fasting glucose, total and low-density lipoprotein (LDL) cholesterol, and with the overall Framingham risk score (p < 0.001 for all), whereas impaired brachial artery FMD correlated with systolic and diastolic blood pressure (p < 0.01). No relationship was observed between carotid IMT and brachial artery FMD for the entire cohort (r = -0.006, p = 0.82) and in subgroups defined by traditional risk factors or by quintiles of carotid IMT and brachial FMD. CONCLUSIONS: In middle-aged healthy men, there is no significant correlation between carotid IMT and brachial artery FMD. This finding suggests that these are unique, independent surrogates that measure different aspects and stages of early atherosclerosis. Further studies are needed to define their role in clinical research and in cardiovascular risk assessment.     

颈动脉内-中膜厚度检测在老年冠心病患者冠状动脉病变中的预测价值

目的 采用彩色多普勒超声检测老年冠状动脉粥样硬化性心脏病（冠心病）患者颈动脉内-中膜厚度（intima-media thickness,IMT）,探讨其在老年患者冠状动脉病变中的预测价值.方法 选择拟诊为冠心病的老年患者121例,按冠状动脉造影结果分组.按冠状动脉狭窄程度分组：阴性对照组（冠状动脉狭窄＜50％）;50％≤冠状动脉狭窄＜70％组;冠状动脉狭窄≥70％组.按累及冠状动脉病变支数分组：阴性对照组（冠状动脉狭窄＜50％）;单支病变组（仅1支冠状动脉狭窄≥50％）;2支病变组（2支冠状动脉狭窄≥50％）;多支病变组（3支及以上的冠状动脉狭窄≥50％）.彩色多普勒超声仪测量颈动脉IMT,对不同冠状动脉病变组的颈动脉IMT、斑块发生率进行比较分析.结果 阴性对照组、50％≤冠状动脉狭窄＜70％组和冠状动脉狭窄≥70％组IMT分别为（0.80±0.22） mm、（0.98±0.17）mm和（1.01±0.25）mm;颈动脉斑块检出率分别为35.0％、94.8％和83.7％.不同冠状动脉狭窄程度组的颈动脉IMT、斑块发生率均显著高于阴性对照组,差异有统计学意义（P＜0.05）;但不同冠状动脉狭窄程度组各组之间颈动脉IMT、斑块发生率比较,差异无统计学意义（P＞0.05）.阴性对照组、单支病变组、二支病变组和三支病变组颈动脉IMT分别为（0.80±0.22）mm、（0.96±0.15）mm、（0.98±0.17）mm和（1.00±0.15）mm;颈动脉斑块检出率分别为35.0％、84.0％、86.7％和83.9％.不同冠状动脉病变支数组的颈动脉IMT、斑块发生率均显著高于阴性对照组,差异有统计学意义（P＜0.05）;但不同冠状动脉病变支数各组之间颈动脉IMT、斑块发生率比较,差异无统计学意义（P＞0.05）.结论 彩色多普勒超声测量颈动脉IMT对冠心病有着重要的预测作用,可望为老年冠心病高危人群筛选提供新的临床手段.