Determinants of coronary compliance in patients with coronary artery disease: An intravascular ultrasound study

Objectives. The aim of this study was to elucidate determinants of coronary compliance in patients with coronary artery disease.Background. Intravascular ultrasound potentially enables in vivo evaluation of coronary artery compliance.Methods. Twenty-seven patients (mean age [±SD] 57 ± 11 years, three women) undergoing coronary angioplasty were studied with intravascular ultrasound imaging. A mechanical intravascular ultrasound system (4.8F, 20 MHz) was used. A total of 58 dilferent coronary segments (proximal to the target angiographic lesion) were studied. Of these, 35 were located in the left anterior descending, 9 in the left main, 8 in the left circumflex and 6 in the right coronary arteries. During intravascular ultrasound imaging, 22 segments (38%) appeared normal, but 36 (62%) had plaque (24 fibrotic, 3 lipidic and 9 calcified). Systolic-diastolic changes in area (ΔA) and pressure (ΔP) with respect to vessel area (A) were used to study normalized compliance (Normalized compliance = [ΔA/AJ/ΔP [mm Hg⁻¹×x 10³]).Results. Lumen area and plaque area were 12.6 ± 5.7 and 3 ± 3 mm², respectively. Plaque was concentric (more than two quadrants) at 10 sites, but the remaining 26 plaques were eccentric. Compliance was inversely related to age (r = −0.34, p < 0.05) but was not related to other clinical variables. Compliance was greater in the left main coronary artery (3.9 ± 2.1 vs. 1.8 ± 1.2 mm Hg⁻¹, p < 0.05) and in coronary segments with normal findings on ultrasound imaging (2.9 ± 1.9 vs. 1.6 ± 1.1 mm Hg⁻¹, p < 0.01). Moreover, at diseased coronary segments compliance was lower in calcified plaques than in other types of plaques (1.2 ± 9.7 vs. 2.3 ± 1.6 mm Hg⁻¹, p < 0.01) but was similar in concentric and eccentric plaques (1.6 ± 1.5 vs. 1.6 ± 0.9 mm Hg⁻¹). Plaque area (r = − 0.38, p < 0.01) was inversely correlated with compliance. On multivariate analysis, only age and plaque area were independently related to compliance.Conclusions. Intravascular ultrasound may be used to evaluate compliance in patients with coronary artery disease. Compliance is reduced with increasing age and is mainly determined by the arterial site and by the presence, size and characteristics of plaque on intravascular ultrasound imaging.     

Comparison of body mass index among patients with versus without angiographic coronary artery disease

We examined body mass index (BMI) in kilograms divided by height in meters squared in 842 patients who underwent coronary angiography for suspected coronary artery disease (CAD) in a 2-month period in 2000 at Baylor University Medical Center. Comparison of the BMI in the 624 patients in whom > or =1 coronary artery was narrowed >50% in diameter to the BMI in the 218 patients with absent or lesser degrees of coronary narrowing disclosed the following: the BMI was >30 (obese) in 209 (33%) versus 92 (42%) patients (p 0.008): 26 to 30 (overweight but not obese) in 233 (37%) versus 80 patients (37%) (p = NS), and BMI < or =25 (ideal) in 182 (29%) versus 46 (21%) patients (p 0.01). Compared with the patients > or =65 years of age, the patients <65 years of age in both groups had a higher frequency of obesity and a lower frequency of ideal body weight. In conclusion, patients with coronary narrowing >50% in diameter were less likely to be obese and more likely to be at ideal body weight than the group of patients with absent or lesser degrees coronary narrowing by angiogram.     

Atropine-induced cardioacceleration and myocardial blood flow in subjects with and without coronary artery disease

Thirty-five patients being studied by coronary cineangiography for diagnosis or evaluation of coronary atherosclerotic occlusive disease had myocardial blood flow determinations at rest and after intravenous administration of atropine sulfate, 1.0 mg. Myocardial blood flow was determined by a coincidence counting system and a single bolus injection of ⁸⁴rubidium chloride.In 10 patients without coronary occlusive disease, heart rate increased by 52 percent and myocardial blood flow by 48 percent (P < 0.001, r = 0.888). In 14 patients with single vessel disease or partial occlusion of two vessels, myocardial blood flow increased by 44 percent and heart rate by 37 percent (P <0.05, r = 0.553). In 11 patients with two or three vessel occlusive disease, heart rate increased by 30 percent whereas myocardial blood flow increased by only 15 percent (r = ?0.172).We conclude that patients with two and three vessel involvement by atherosclerotic occlusive disease are unable to increase nutrient myocardial blood flow in response to atropine-induced Cardioacceleration to the same degree as patients without coronary disease or with less extensive disease. The observation may be of therapeutic importance because of the potential that administration of atropine may have for inducing myocardial ischemia in such patients.     

Arterial compliance adds to conventional risk factors for prediction of angiographic coronary artery disease

Background

Arterial compliance is related to left ventricular hypertrophy and risk for cardiovascular disease events; however, its association with coronary artery stenosis remains uncertain. We sought to assess the relation between lower extremity arterial compliance and presence of angiographically defined coronary artery disease.

Methods

Lower extremity arterial compliance was measured with the use of a noninvasive air plethysmography technique in 376 subjects undergoing routine diagnostic coronary angiography.

Results

Measures of calf arterial compliance were significantly associated with the presence of one or more stenoses ≥50% compared with no stenoses, even after adjustment for age, sex, smoking, diabetes, hypertension, hypercholesterolemia, and obesity (P = .03). Measures of thigh arterial compliance were also lower in subjects with disease, although this association did not reach statistical significance (P = .07). Receiver operator curves illustrate the incremental predictive ability of calf arterial compliance over and above age, sex, and conventional risk factors.

Conclusions

Lower extremity arterial compliance is associated with presence of significant coronary stenoses in a cardiac catheterization laboratory referral population. This observation lends support for additional efforts to determine the utility of vascular stiffness measures in both clinical and pre-clinical populations to guide treatment and prevention efforts.     

Coronary artery distensibility assessed by 3.0 Tesla coronary magnetic resonance imaging in subjects with and without coronary artery disease

Coronary vessel distensibility is reduced with atherosclerosis and normal aging, but direct measurements have historically required invasive measurements at cardiac catheterization. Therefore, we sought to assess coronary artery distensibility noninvasively using 3.0 Telsa coronary magnetic resonance imaging (MRI) and to test the hypothesis that this noninvasive technique can detect differences in coronary distensibility between healthy subjects and those with coronary artery disease (CAD). A total of 38 healthy, adult subjects (23 men, mean age 31 ± 10 years) and 21 patients with CAD, diagnosed using x-ray angiography (11 men, mean age 57 ± 6 years) were studied using a commercial whole-body MRI system. In each subject, the proximal segment of a coronary artery was imaged for the cross-sectional area measurements using cine spiral MRI. The distensibility (mm Hg(-1) × 10(3)) was determined as (end-systolic lumen area - end-diastolic lumen area)/(pulse pressure × end-diastolic lumen area). The pulse pressure was calculated as the difference between the systolic and diastolic brachial blood pressure. A total of 34 healthy subjects and 19 patients had adequate image quality for coronary area measurements. Coronary artery distensibility was significantly greater in the healthy subjects than in those with CAD (mean ± SD 2.4 ± 1.7 mm Hg(-1) × 10(3) vs 1.1 ± 1.1 mm Hg(-1) × 10(3), respectively, p = 0.007; median 2.2 vs 0.9 mm Hg(-1) × 10(3)). In a subgroup of 10 patients with CAD, we found a significant correlation between the coronary artery distensibility measurements assessed using MRI and x-ray coronary angiography (R = 0.65, p = 0.003). In a group of 10 healthy subjects, the repeated distensibility measurements demonstrated a significant correlation (R = 0.80, p = 0.006). In conclusion, 3.0-Tesla MRI, a reproducible noninvasive method to assess human coronary artery vessel wall distensibility, is able to detect significant differences in distensibility between healthy subjects and those with CAD.     

C-reactive protein and angiographic coronary artery disease: independent and additive predictors of risk in subjects with angina

OBJECTIVES: The objective of this study was to determine the prognostic value of C-reactive protein (CRP) independent of coronary angiographic findings. BACKGROUND: High sensitivity CRP, a marker of inflammation, predicts risk of cardiovascular events. However, it is uncertain whether it remains predictive once angiographic findings are considered. METHODS: A total of 2,554 patients with angina but without acute myocardial infarction (MI) were studied angiographically; 1,848 patients had coronary artery disease (CAD) and 706 patients did not. Coronary artery disease was quantified in five ways and combined for a CAD score. C-reactive protein was measured and patients were followed for up to five years for death or MI. RESULTS: C-reactive protein correlated with the extent of CAD, but correlation coefficients were low (0.02 to 0.08). Of angiographic measures, the CAD score best predicted future events (hazard ratio [HR] = 1.8 [1.2 to 2.6], p = 0.004, for CAD score > 4). C-reactive protein > or = 1.0 mg/dl was predictive in both patients without CAD (HR = 2.3 [0.9 to 5.5], p = 0.07) and with CAD (HR = 2.1 [1.5 to 3.1], p = 0.0001). Multivariate adjustment resulted in little change in HR. C-reactive protein retained predictive value within each quintile of CAD score. C-reactive protein and CAD independently and additively contributed to the risk prediction: low CRP and lowest CAD score was associated with lowest risk, and high CRP and highest CAD score was associated with the highest risk, with a 10-fold difference between extremes (2.5% vs. 24%). CONCLUSIONS: C-reactive protein correlates with extent of CAD, but the degree of correlation is low. Severity/extent of CAD and CRP are independent and additive predictors of risk. Therapy should target CRP-associated risk as well as angiographically evident stenosis.     

Association of ankle-brachial index with severity of angiographic coronary artery disease in patients with peripheral arterial disease and coronary artery disease

The ankle-brachial index (ABI) was correlated with the severity of coronary artery disease (CAD) in 273 patients, mean age 71 years, with peripheral arterial disease and angiographically obstructive CAD (> 50% occlusion). Of 155 patients with an ABI < 0.40, 130 (84%) had 3- or 4-vessel CAD, 17 (11%) had 2-vessel CAD and 8 (5%) had 1-vessel CAD. Of 80 patients with an ABI of 0.40-0.69, 37 (46%) had 3- or 4-vessel CAD, 33 (41%) had 2-vessel CAD and 10 (13%) had 1-vessel CAD. Of 38 patients with an ABI of 0.70-0.89, 10 (26%) had 3- or 4-vessel CAD, 16 (42%) had 2-vessel CAD and 12 (32%) had 1-vessel CAD. The lower the ABI, the higher the prevalence of 3- or 4-vessel CAD and the lower the prevalence of 1-vessel CAD.     

Inverse association between serum concentrations of neopterin and antioxidants in patients with and without angiographic coronary artery disease

Neopterin is released from human monocyte-derived macrophages upon stimulation with interferon-gamma and is a sensitive indicator for cellular immune activation. Furthermore, reactive oxygen species (ROS) are produced in case of immune activation and inflammation. In a cross-sectional approach, plasma concentrations of neopterin and of antioxidant compounds and vitamins were compared in 1463 patients investigated by coronary angiography, which were recruited within the LUdwigshafen RIsk and Cardiovascular Health (LURIC) study. Serum neopterin concentrations were higher in patients with coronary artery disease (CAD; mean+/-S.D.: 8.7+/-7.3 nmol/L) compared to controls (7.4+/-5.0 nmol/L; Welch's t-test: p<0.001). Mean concentrations of ascorbic acid (p<0.0001), gamma-tocopherol (p<0.05), lycopene (p<0.001), lutein+zeaxanthin (p<0.05), alpha-carotene (p<0.05) and beta-carotene (p<0.05) were lower in CAD than in controls. Neopterin concentrations correlated with CAD-score (r(s)=0.156; p<0.0001) and inversely with antioxidants lycopene (r(s)=-0.277; p<0.0001) and lutein+zeaxanthin (r(s)=-0.175; p<0.0001) levels and with vitamins ascorbic acid (r(s)=-0.207; p<0.0001) and alpha-tocopherol (r(s)=-0.105; p<0.0001). The study demonstrates that higher neopterin production is associated with lower concentrations of antioxidant compounds in patients at risk for atherosclerosis. Results suggest that lower concentrations of antioxidant compounds may relate to higher grade of chronic immune activation in patients.     

Prevalence of coronary artery disease in a general population without suspicion of coronary artery disease: angiographic analysis of subjects aged 40 to 70 years referred for catheter ablation therapy.

BACKGROUND: The prevalence of coronary vessel wall alterations in the general population is not known. Therefore, the aim of our study was to determine the prevalence of coronary artery disease in persons in whom the underlying disease was not related to coronary artery disease and could therefore be regarded as a near normal population. METHODS: We included 331 consecutive patients (173 men, 158 women, aged between 40 and 70 years) who were referred for catheter ablation of an accessory pathway (67.4% ) or atrioventricular-node modification (32.6%) and who underwent coronary angiography as part of their routine baseline evaluation before radiofrequency current application. Most of the patients (79%) of this cohort were free of symptoms of coronary artery disease. Based on visual inspection of coronary angiograms in multiple projections, patients were classified to have one-, two- or three-vessel disease if stenoses greater than 50% of lumen diameter were present. In addition, diffuse vessel wall alterations were assessed using two different score systems. RESULTS: The prevalence of coronary artery disease in this near normal population was 7.3%, with a significant difference in coronary asymptomatic (3.8%) vs symptomatic patients (17.1%). Mean levels of total cholesterol and other risk factors were not significantly different in patients with coronary artery disease compared to those without. But levels of low-density lipoprotein (LDL) cholesterol and lipoprotein(a) were significantly higher and high-density (HDL) cholesterol lower in patients with a stenosis or extent score higher than zero compared to a score of zero. The values of all vessel scores evaluating the extent of critical and diffuse coronary vessel alterations were very low in patients affected with coronary artery disease, indicating a low degree of diffuse alteration of the vessel wall. CONCLUSIONS: The prevalence of coronary artery disease with at least one critical stenosis in subjects aged 40-70 years with an average cholesterol level of 238+/-42 mg. dl(-1)is 7.3%.     

青年男性冠状动脉病临床与冠状动脉造影分析

目的 探讨青年男性（〈４０岁）心绞痛临床与冠状动脉造影（ＣＡＧ）的特点。方法 将９０例青年男性心绞痛患者按心肌梗塞（ＭＩ）（２０例）、典型心绞痛（３４例）、不典型心绞痛（３６例）分为三组并行ＣＡＧ。结果 有冠状动脉病变（ＣＡＤ）者４７例（５２．２％）。ＭＩ组１８例（９０％）,典型组２２例（６４．７％）,不典型组７例（１９．４％）。三组之间ＣＡＤ检出率比较有显著性差异,ＭＩ组〉典型组〉不典型组。冠脉     

Impact of acute caffeine ingestion on endothelial function in subjects with and without coronary artery disease

Although coffee is a widely used, pharmacologically active beverage, its impact on the cardiovascular system is controversial. To explore the effect of acute caffeine ingestion on brachial artery flow-mediated dilation (FMD) in subjects without coronary artery disease (CAD; controls) and patients with CAD, we prospectively assessed brachial artery FMD in 40 controls and 40 age- and gender-matched patients with documented stable CAD on 2 separate mornings 1 week to 2 weeks apart. After overnight fasting, discontinuation of all medications for ≥12 hours, and absence of caffeine for >48 hours, participants received capsules with caffeine 200 mg or placebo. One hour after drug ingestion, participants underwent brachial artery FMD and nitroglycerin-mediated dilation (NTG) using high-resolution ultrasound. As expected, patients with CAD were more often diabetic, hypertensive, obese, dyslipidemic, and smoked more than controls (p <0.01 for all comparisons). Aspirin, Clopidogrel, angiotensin-converting enzyme inhibitors, β blockers, and statins were significantly more common in patients with CAD than in controls (p <0.01 for all comparisons). At baseline, FMD, but not NTG, was significantly lower in patients with CAD compared to controls. Acute caffeine ingestion significantly increased FMD (patients with CAD 5.6 ± 5.0% vs 14.6 ± 5.0%, controls 8.4 ± 2.9% vs 18.6 ± 6.8%, p <0.001 for all comparisons) but not NTG (patients with CAD 13.0 ± 5.2% vs 13.8 ± 6.1%, controls 12.9 ± 3.9% vs 13.9 ± 5.8%, p = NS for all comparisons) and significantly decreased high-sensitivity C-reactive protein (patients with CAD 2.6 ± 1.4 vs 1.4 ± 1.2 mg/L, controls 3.4 ± 3.0 vs 1.2 ± 1.0 mg/L, p <0.001 for all comparisons) in the 2 groups compared to placebo. In conclusion, acute caffeine ingestion significantly improved endothelial function assessed by brachial artery FMD in subjects with and without CAD and was associated with lower plasma markers of inflammation.     

Clinical and angiographic factors associated with progression of coronary artery disease

To characterize the clinical and angiographic factors associated with progression of coronary atherosclerosis, 313 consecutive medically treated patients who had had two coronary arteriograms 3 to 119 months (mean 39 +/- 25) apart were studied. One hundred eighty-one patients underwent recatheterization for stable angina, 52 for unstable angina and 80 for various other reasons. In addition to the conventional angiographic features present at the first angiographic study (number of diseased vessels 1.5 +/- 0.8, ejection fraction 59 +/- 11%), an extent score was defined based on the number of coronary segments with 5 to 75% narrowings from a 15 segment coding system. Multivariate logistic regression identified four independent predictors of progression of coronary artery disease: the interval between studies (p less than 0.0001), unstable angina (p less than 0.0001), a high extent score (p = 0.0001) and young age (p = 0.0026). In a subset of 74 patients aged 50 years or younger with, at the time of the first evaluation, an extent score of 4 or more, the probability of progression between 2 and 4 years and after 4 years was, respectively, 80 and 90% compared with 50% for the other patients. Risk stratification for progression of coronary artery disease can thus be obtained.     

Large brachial artery diameter is associated with angiographic coronary artery disease in women

Background Noninvasive methods are needed for the identification of women at highest risk for coronary artery disease (CAD) who might benefit most from aggressive preventive therapy. Identification of brachial artery atherosclerosis, which correlates with coronary artery atherosclerosis, may be useful to estimate or stratify CAD risk. Because atherosclerosis disrupts the arterial architecture that regulates vessel size, we hypothesized that noninvasively measured large brachial artery diameter is a manifestation of atherosclerosis that is associated with angiographic CAD in women with chest pain. Methods We examined 376 women (mean age, 57.1 years) with chest pain in the National Heart, Lung, and Blood Institute's Women's Ischemia Syndrome Evaluation study who underwent B-mode ultrasound scan measurement of brachial artery diameter at rest and during hyperemic stress (to quantify flow-mediated dilation), quantitative coronary angiography, and risk factor assessment. Results Large resting brachial artery diameter was associated with significant angiographic CAD (3.90 ± 0.79 mm vs 3.52 ± 0.59 mm in women with CAD vs no CAD; P < .001). Impaired flow-mediated dilation, which correlated with resting diameter (r = −0.17; P = .001), was weakly associated with significant CAD (2.74% ± 7.11% vs 4.48% ± 9.52% in CAD vs no CAD; P = .046). After adjustment for age, body size, and CAD risk factors, women with large resting brachial artery diameters (>4.1 mm) had 3.6-fold increased odds (95% confidence interval, 1.8 to 7.1; P < .001) of significant angiographic CAD compared with those with small brachial arteries (≤3.6 mm). Conclusion Large resting brachial artery diameter is an independent predictor of significant CAD in women with chest pain. Therefore, a simple ultrasonographic technique may be useful in the identification of women with chest pain who are at increased risk for CAD. (Am Heart J 2002;143:802-7.)     

Noninvasive and angiographic evaluation of coronary artery disease in patients with peripheral vascular disease

The accuracy of exercise testing for detection of coronary artery disease in a population with a high incidence of claudication was evaluated in 58 consecutive patients with abdominal aortic aneurysms or lower extremity occlusive disease. Each patient was evaluated by history and physical examination, symptom-limited testing with exercise treadmill, arm ergometry and exercise radionuclide ventriculography. An algorithm was designed that retrospectively examined the results of each test in a stepwise fashion to simulate a clinical decision-making process. The results of the clinical examination, each of the exercise tests and the noninvasive diagnostic algorithm were compared with the results of coronary arteriography. The predictive accuracy of the clinical evaluation was 36%, treadmill stress testing 57%, treadmill stress plus arm ergometry 74%, exercise radionuclide ventriculography 57% and the noninvasive diagnostic algorithm 89%. When discriminant analysis was applied to all of the exercise variables, no individual test improved the accuracy of the noninvasive diagnostic algorithm. When the analysis considered only individual variables without the algorithm, the model correctly classified only 67% of the patients. Thus, accurate noninvasive evaluation of coronary artery disease is possible in patients with severe peripheral vascular disease when care is taken to design exercise protocols that allow adequate stress on the cardiovascular system.     

Correlation of coronary angioscopic to angiographic findings in coronary artery disease

An Olympus ultrathin fiberscope, 1.8 mm outer diameter, was inserted intraluminally into 11 stenoses of the left anterior descending and circumflex coronary arteries in 8 patients at coronary bypass surgery. Intraluminal views were obtained by coupling the angioscope to a color video camera and videotape recorder, and compared with preoperative coronary angiographic findings in right and left anterior oblique views. Atherosclerotic plaque was observed as yellow-white mass attached onto the luminal lining, which may be large enough to virtually obliterate the vascular lumen. Angioscopy provided a topographic view and cross-sectional picture of stenosis not observed by angiography. Single-plane angioscopic cross-sectional stenotic lumens correlated well (r = 0.90, p less than 0.001) with calculated angiographic luminal narrowings. However, with subtotal obstruction, lesion length must be assessed angiographically. Coronary angioscopy can be a useful adjunct to angiography by providing the added dimension of the true cross-sectional view of obstruction.     

Fasting plasma glucose correlates with angiographic coronary artery disease prevalence and severity in Chinese patients without known diabetes

Type 2 diabetes mellitus is a risk factor for coronary artery disease (CAD). While there is a clear association of fasting plasma glucose (FPG) with microvascular complications, the risk for CAD conferred by FPG is relatively less clear. Therefore, we investigate the association between different FPG and the prevalence and severity of angiographic CAD in high-risk Chinese patients without known diabetes. Among 1,419 subjects who were to undergo coronary angiography for the confirmation of suspected myocardial ischemia, 906 subjects without known diabetes were included in this study and categorized into four groups according to the level of FPG: group 1, ≤5.5 mmol/l; group 2, 5.6–6.0 mmol/l; group 3, 6.1–6.9 mmol/l; and group 4, ≥7.0 mmol/l. Significant angiographic CAD was defined as ≥50 % lumen diameter reduction in at least one major coronary artery in a given subject. The severity and extent of coronary atherosclerosis were defined as the number of diseased vessels, the proportion of totally occluded vessel and the Gensini score. Associations between FPG and the prevalence and severity of CAD were assessed by logistic and linear stepwise regression analyses. The angiographic CAD prevalence, the number of diseased vessels, the totally occluded vessel, and the Gensini score increased corresponding to increasing FPG levels from ≤5.5 mmol/l to 5.6–6.0 mmol/l to 6.1–6.9 mmol/l to ≥7.0 mmol/l (P < 0.05). The FPG had significant association with angiographic CAD (adjusted OR, 1.53; 95 % CI, 1.19–1.98; P = 0.001) and the Gensini score (standardized regression coefficient = 0.172, P = 0.011). Compared with group 1, group 2, 3 and 4 demonstrated significantly higher CAD prevalence after adjustment (adjusted OR, 1.61 [1.16–2.19]; P = 0.015 for group 2; 1.49 [1.11–2.59]; P = 0.027 for group 3; and 4.19 [2.85–6.16]; P = 0.024 for group 4, respectively). FPG group was also significantly associated with the Gensini score (Standardized coefficients, 0.185; P = 0.007, respectively). FPG was an independent risk factor for the prevalence and severity of significant angiographic CAD in our study population. The severity of angiographic CAD increased along with the increasing FPG levels even in prediabetic state.     

Hyperinsulinemia in subjects with and without coronary artery disease: a preliminary study from North India

BACKGROUND: Hyperinsulinemia has been associated with obesity, hypertension, diabetes, and coronary artery disease. However, it is not clear whether hyperinsulinemia by itself is a risk factor for coronary artery disease in the absence of obesity, diabetes, and hypertension. Therefore, we conducted a study to evaluate the role of hyperinsulinemia in coronary artery disease in the absence of diabetes, hypertension, and obesity. METHODS AND RESULTS: A total of 80 cases and 50 controls were studied. Only non-diabetic, normotensive, nonobese men (body-mass index < or = 25) were included. The presence of valvular heart disease or an acute coronary event in the past 6 weeks were exclusion criteria. Serum insulin levels were measured in fasting samples by ELISA assay. The mean fasting insulin was 17.0+/-16.5 microIU/ml and 13.3+/-12.9 microIU/ml in the control and study groups, respectively (reference range 1.5-15.6 microIU/ml). There was no significant association between coronary artery disease and the surrogate markers of insulin resistance, namely, fasting insulin (p value 0.367) and homeostasis model assessment of insulin resistance (p value 0.589). CONCLUSIONS: A high-normal fasting insulin level was present in non-diabetic, nonhypertensive, and nonobese men in the Indian population. We suggest that insulin resistance may not per se be an independent risk factor for coronary artery disease. It may be an innocent bystander in coronary artery disease in an obese, hypertensive, and diabetic population. However, due to our small sample size, further studies are required in this direction.