Plasma homocysteine level and development of coronary artery disease

BACKGROUND: The plasma level of homocysteine is an independent risk factor for atherosclerotic vascular disease. The relationship between plasma homocysteine level and the onset of coronary artery disease (CAD) has not been established. OBJECTIVE: To investigate the relationship between plasma homocysteine level and the age at which CAD was diagnosed. METHODS: Fifty-seven male patients aged < or = 65 years (mean age 53 years) with angiographically proven symptomatic CAD seen consecutively and 138 age-matched male control subjects (mean age 52 years) free from atherosclerotic vascular disease were studied. They were divided into two subgroups, a group of younger subjects (aged < or = 55 years) and a group of older subjects (aged 56-65 years). RESULTS: Plasma homocysteine levels in CAD patients significantly exceeded those of control subjects (means 13.4 versus 10.6 nmol/ml, P = 0.0002). Plasma homocysteine level of subjects in younger CAD group was significantly higher than that of subjects in older CAD group (15.0 versus 11.3 nmol/ml, P = 0.03), and age and logarithmically transformed plasma homocysteine level exhibited a significant negative correlation (r = -0.28, P = 0.03) for subjects in CAD group. Among control subjects, members of our two age subgroups had similar plasma homocysteine levels. Younger CAD patients had significantly higher plasma homocysteine levels than did younger controls (15.0 versus 10.4 nmol/ml, P < 0.0001). However, for older groups there was no significant difference between plasma homocysteine levels in CAD patients and controls (11.3 versus 10.9 nmol/ml). Multiple regression analysis showed that only logarithmically transformed plasma homocysteine level was a significant predictor for age of onset of CAD. CONCLUSION: An elevated level of plasma homocysteine is more important in the development of premature CAD than it is in that of late-onset CAD among men.     

Poor coronary collateral circulation is associated with higher concentrations of soluble adhesion molecules in patients with single-vessel disease

OBJECTIVE: As the endothelium and inflammatory cells play a crucial role in the development of collaterals after a sudden or slowly progressing stenosis of coronary arteries, the levels of soluble endothelial adhesion molecules (CAMs) including vascular cell adhesion molecule (VCAM-1) intercellular adhesion molecule-1 (ICAM-1) and E-selectin were compared between patients with poor coronary collaterals and patients with well-developed collaterals. METHODS: In the study, 97 non-diabetic subjects with single-vessel disease were included. Collateral supply to the stenotic coronary artery was determined by angiographic grading system of 0-3 (Rentrop et al. J Am Coll Cardiol 1985; 5:587-592). Serum levels of adhesion molecules were measured by enzyme-linked immunosorbent assay. RESULTS: Patients were divided into two groups according to the collateral degree (group A: 50 patients with grade 0 and 1; group B: 47 patients with grade 2 and 3 collaterals). The groups were well matched with respect to baseline clinical and angiographic characteristics. Levels of soluble VCAM-1 (mean+/-SEM; 875+/-26.6 versus 742.7+/-35.1 ng/ml; P=0.004), ICAM-1 (322.4+/-12.4 versus 269.4+/-13.3 ng/ml; P=0.005), and E-selectin (43.6+/-2.6 versus 33+/-2.4 ng/ml; P=0.004) were found to be significantly higher in group A in comparison with group B. In addition, when patients were divided into four groups according to the collateral degree, patients with grade 0 collaterals had the highest values and those with grade 3 collaterals had the lowest values for all these molecules. CONCLUSIONS: We concluded that poor collateral circulation is associated with increased levels of soluble CAMs in patients with obstructive coronary artery disease. However, further studies are needed to elucidate the exact role of these inflammatory markers in the setting of poor collateral circulation.     

Pravastatin promotes coronary collateral circulation in patients with coronary artery disease

BACKGROUND: Previous studies suggested that hydroxymethylglutaryl coenzyme A reductase inhibitor (statin) promotes collateral circulation in ischemic limbs of rabbits. The present study was designed to determine the association between treatment with pravastatin and the development of coronary collateral circulation as assessed by the Rentrop Score in patients with coronary artery disease (CAD) in a case-control study. DESIGN: The study included patients who had one (1-V), two (2-V) or three (3-V) significantly stenosed vessels. Patients who did and did not receive pravastatin were defined as case participants (n = 42) and control participants (n = 100), respectively. RESULTS: The case participants included a higher percentage of 3-V patients with a Rentrop Score 1 compared to the control participants but there was no difference among 1-V and 2-V patients, suggesting that pravastatin was associated with coronary collateral circulation independent of the number of stenosed vessels. Patients with 3-V disease who were treated with pravastatin were most likely [odds ratio (confidence interval), 17.4 (4.4-115)] to develop collateral circulation, as assessed by multiple logistic regression analysis. CONCLUSIONS: Treatment with pravastatin was associated with the development of collateral circulation in patients with CAD, suggesting that such action constitutes part of the pleiotropic effects of statin.     

Angiotensin-converting enzyme inhibitor promotes coronary collateral circulation in patients with coronary artery disease.

Previous studies have suggested that angiotensin-converting enzyme inhibitors (ACEI) promote collateral circulation in ischemic limbs of rabbits. The present study was designed to determine the association between treatment with ACEI and the development of coronary collateral circulation, as assessed by the Rentrop Score, in patients with coronary artery disease (CAD) in a case - control study. Subjects included 456 patients with angina who underwent coronary angiography. Those who had one (1-V), two (2-V) or three (3-V) significantly stenosed vessels, and who received only ACEI without any other anti-hypertensive medication were defined as cases (n=33), and age, sex and body mass index-matched subjects (n=56) were selected as controls. Among 1-V patients, but not 2-V or 3-V patients, the cases included a higher percentage of patients with Rentrop Score of at least 1 than the controls, suggesting that ACEI was associated with coronary collateral circulation. Patients with 1-V disease who were treated with ACEI were most likely [odds ratio (confidence interval): 6.1 (1.4-30.1)] to develop collateral circulation, as assessed by a multiple logistic regression analysis. Therefore, treatment with ACEI was associated with the development of collateral circulation in patients with CAD, suggesting that such an action is associated with bradykinin production by ACEI.     

冠心病患者冠状动脉侧支循环形成的相关因素

目的:探讨冠状动脉侧支循环形成的意义及影响侧支循环形成的相关因素。方法:冠状动脉造影中发现有侧支循环形成者47例作为研究组,以病变程度相同但无侧支循环形成者58例作为对照组;同时超声心动图检查病变局部室壁运动情况。结果:侧支循环形成与糖尿病、吸烟呈负相关,与服用他汀类药物呈正相关,而与性别、年龄、胸痛时间、有无高血压病、有无高脂血症、家族史、冠状动脉病变支数、服用ACEI类、硝酸酯类药物无关。结论:侧支循环多出现在病变严重的冠心病患者,糖尿病、吸烟是侧支循环形成的不利因素,服用他汀类药物能促进侧支循环形成;糖尿病患者即使形成侧支循环,对心功能的保护作用也较差。     

Hematological parameters and coronary collateral circulation in patients with stable coronary artery disease

BACKGROUND:

Although hematological parameters have been associated with prognosis in patients with various cardiovascular diseases, their relationship with coronary collateral (CC) circulation in patients with stable coronary artery disease (CAD) is unknown.

OBJECTIVE:

To investigate the relationship between hematological parameters and CC vessel development in patients with stable CAD.

METHODS:

A total of 96 patients who underwent coronary angiography were retrospectively enrolled. All study participants had at least one occluded major coronary artery. Development of CCs was classified using the method of Rentrop. Rentrop grades of 0 and 1 indicate poor CCs, whereas grades 2 and 3 indicate good CCs. Hematological parameters, including mean platelet volume (MPV) and neutrophil/lymphocyte (N/L) ratio, were measured. Multivariate logistic regression analysis was performed to identify independent variables.

RESULTS:

The MPV and N/L ratio were significantly higher in the poor CC group compared with the good CC group. Negative correlations were found in the analyses comparing Rentrop score with MPV and N/L ratio (r=−0.274; P=0.012 and r=−0.339; P=0.001, respectively). In multivariate analysis, the N/L ratio was independently related to CC circulation (OR 0.762 [95% CI 0.587 to 0.988]; P=0.04).

CONCLUSION:

The results suggest that N/L ratio and MPV are associated with poor CCs, and a high N/L ratio is a significant predictor of poor CC development in patients with stable CAD.     

Plasma homocysteine level and the angiographic extent of coronary artery disease

Recent epidemiologic studies have shown that moderately elevated plasma homocysteine concentrations are associated with an increased risk for the development of atherosclerotic cardiovascular diseases. But, it is not known whether moderate hyperhomocysteinemia is associated with the angiographic extent of atherosclerotic cardiovascular disease in patients with coronary artery disease (CAD). A possible relationship was investigated between admission plasma homocysteine level and the angiographic extent of coronary artery disease in patients with CAD. In this study, 156 consecutive patients presenting with coronary artery disease (group 1) and control group (group 2) of 35 age-matched persons with normal coronary angiography were enrolled. Blood samples for homocysteine were obtained on admission. Plasma homocysteine concentration was measured with high-performance liquid chromatography with fluorescence detection. Radiographs from coronary angiography were viewed and scored using Sullivan's method to assess the atherosclerotic involvement of coronary artery disease. There were significant elevations in homocysteine level in group 1 compared to group 2 (15.59 +/-5.7 micromol/L, 9.24 +/-1.50 micromol/L; respectively, p < 0.001). All scores (demonstrated angiographic extension of CAD) correlated significantly with plasma homocysteine levels; however, the Sullivan's extent score correlated more closely (r = 0.68, p < 0.001) than both the stenosis score (r = 0.44, p < 0.01) and vessel score (r = 0.35, p < 0.05). Elevated homocysteine levels in patients with coronary artery disease correlated with the angiographic extent of atherosclerotic disease.     

Significance of collateral circulation in patients with left main coronary artery disease

Fifty patients with left main coronary artery disease were studied to evaluate the functional role of collateral circulation. The left main was narrowed 50-70% in 22 patients (group I), and more than 70% in 28 patients (group II). Significant disease in the other vessels was equally common in each group. There was no significant difference in the incidence of inter- and intracoronary collaterals in the two groups. Fifteen patients with no collaterals were compared with 35 patients with collaterals, and to a subset of 11 patients with very rich right-to-left collaterals, and there was no significant difference in historic or ECG evidence of old infarction, duration of angina, incidence of unstable angina, left ventricular end-diastolic pressure, cardiac index, ejection fraction, or segmental contraction abnormalities. We conclude that there is no evidence of protective effect of collateral vessels in patients with left main disease.     

Mildly decreased glomerular filtration rate is associated with poor coronary collateral circulation in patients with coronary artery disease

Background:

The aim of this study was to evaluate the association between mildly decreased glomerular filtration rate (GFR) and coronary collateral circulation (CCC).

Hypothesis:

There would be an association between mildly decreased GFR and CCC.

Methods:

Patients who had an occlusion in at least 1 major coronary artery were included in this study. Patients with severely and moderately decreased GFR were excluded. Patient data were obtained from their files. To classify CCC, we used the Rentrop classification. Patients were classified as having poor CCC (Rentrop grades 0 to 1) or good CCC (Rentrop grades 2 to 3). We used the Modification of Diet in Renal Disease (MDRD) equation to calculate GFR. Mildly decreased GFR was defined as 60 mL/min per 1.73 m² ≥ eGFR ≤89 mL/min per 1.73 m² according to the MDRD definition. Multivariate logistic regression analysis was performed to determine independent variables.

Results:

The study group consisted of 299 patients. Ninety‐three patients had poor CCC and 206 patients had good CCC. The frequency of mildly decreased GFR was higher in the poor CCC group than in the good CCC group (P<0.001). Also, the frequency of diabetes and dyslipidemia, and the plasma high sensitive C‐reactive protein levels, were higher in the poor CCC group (P = 0.003, P = 0.018, P<0.001, respectively). Logistic regression analysis revealed that eGFR is an independent predictor of CCC (B = 1.68; odds ratio = 5.4; P<0.001; 95% confidence interval, 3.1–9.4).

Conclusions:

We found that CCC was worse in patients with mildly decreased GFR compared to patients with normal GFR in patients with coronary artery disease. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Impact of coronary collateral circulation on QT dispersion in patients with coronary artery disease

OBJECTIVE: The aim of this study was to assess the effect of coronary collateral circulation (CCC) on QT dispersion (QTD) in coronary artery disease. BACKGROUND: A prolonged QTD has been linked to increased heterogeneity of ventricular repolarization implicated in the genesis of ventricular arrhythmias and has been associated with an adverse prognosis in patients with coronary artery disease. METHOD: CCC and corrected QTD (QTcD) were established in patients who had at least 85% stenosis in the left anterior descending coronary artery or in proximal part or in the body of the right coronary artery. Furthermore, left ventricular function score was determined for all the patients. RESULTS: While CCC was not present (CCC grade 0) in 32 patients, 68 patients were observed with CCC (CCC grade > or =1). Mean QTcD was higher in patients who had CCC grade > or =1 than in patients with grade 0 (64.3+/-3.5 and 46.8+/-2.7, respectively, P=0.002). We detected a significant correlation between the collateral score and QTcD (r=0.354, P=0.001). CCC grade > or =1 patients had higher mean left ventricular function scores than grade 0 patients (P=0.048). Left ventricular function score and QTcD were observed to be correlated (r=0.200, P=0.046). CONCLUSION: CCC in chronic coronary artery disease was not established to have a positive decreasing effect on QTcD. On the contrary, QTcD values were observed to be even higher in patients with well developed CCC. Further research including larger series and long-term follow-up is required to investigate this issue.     

冠心病预后与冠状动脉侧支循环的关系

目的：研究冠心病（CHD）预后与冠状动脉侧支循环的关系。方法：依据冠状动脉造影结果98例患者被分为CHD无侧支循环组（62例）、CHD有侧支循环组（20例）、正常对照组（16例）,分析各组患者的临床资料。结果：CHD组（无论有无侧支循环）与正常对照组相比,除糖尿病发病率较高外（P〈0.01）,其他CHD易患因素差异均无显著性（P〉0.05）;有侧支循环与无侧支循环CHD患者相比,主要CHD易患因素、不稳定型心绞痛的发生率差异均无显著性（P〉0.05）;但无侧支循环患者左室射血分数〈50%患者比率（29.0%比10.0%）,心肌梗死（61.3%比30.0%）、室壁瘤（22.6%比0）的发生率较有侧支循环患者显著增加（P〈0.01）。结论：侧支循环存在与否与冠心病患者预后有关。     

Relation of coronary collateral circulation with epicardial fat volume in patients with stable coronary artery disease

Objective

To investigated the relationship between epicardial fat volume (EFV) and coronary collateral circulation (CCC) in patients with stable coronary artery disease (CAD).

Methods

The study population consisted of 152 consecutive patients with CAD who underwent coronary angiography and were found to have at least 95% significiant lesion in at least one major coronary artery. EFV was assessed utilizing 64-multislice computed tomography. The patients were classifield into impaired CCC group (Group 1, Rentrop grades 0−1, n = 58), or adequate CCC (Group 2, Rentrop grades 2−3, n = 94).

Results

The EFV values were significantly higher in paitients with adequate CCC than in those with impaired CCC. In multivariate logistic regression analysis, EFV (OR = 1.059; 95% CI: 1.035−1.085; P = 0.001); and presence of angina were independent predictors of adequate CCC. In receiver-operating characteristic curve analysis, the EFV value > 106.5 mL yielded an area under the curve value of 0.84, with the test sensitivity of 49.3%, and with 98.3% specifity.

Conclusions

High EFV, and the presence of angina independently predict adequate CCC in patients with stable coronary artery disease. This association offers new diagnostic opportinities to assess collateral flow by conventional ultrasound techniques.     

Comparison of coronary collateral circulation in diabetic and nondiabetic patients suffering from coronary artery disease.

BACKGROUND AND HYPOTHESIS: Although it is well established that diabetes mellitus (DM) induces more severe coronary artery disease (CAD), it is not known whether it contributes to the development of coronary collateral circulation. The present study examines coronary collateral circulation in diabetic and nondiabetic patients with angiographically verified CAD. METHODS: The study group consisted of 463 diabetic patients (382 men, 81 women) with a mean age of 60.3 +/- 8.8 years, and 227 nondiabetic subjects (159 men, 68 women) with a mean age of 59.2 +/- 9 years. The extension and functional capacity of coronary collateral circulation was assessed according to the Cohen and Rentrop grading system of 0 to III. RESULTS: We found that diabetic patients had grade III collateral circulation more frequently than nondiabetic subjects (13.2 vs. 8.5%, p < 0.01). This finding was even more pronounced in diabetic men aged < 55 years compared with both nondiabetic men (20 vs. 3.4%, p < 0.001) and diabetic women (20 vs. 2.2%, p < 0.001). Grade III collateral circulation was found to develop mainly at the left anterior descending (LAD) coronary artery and the right coronary artery (RCA), where complete occlusions of coronary arteries usually occur. CONCLUSIONS: Diabetic patients with CAD develop more extensive coronary collateral circulation than nondiabetic subjects, especially men aged < 55 years. The collateral circulation mainly develops at the LAD and RCA.     

Effect of obesity on coronary collateral vessel development in patients with coronary artery disease

The purpose of this study was to compare coronary collateral circulation and with other risk factors in patients with coronary artery disease and different body mass index. Between January 1999 and December 2001, of 867 patients who underwent angiography for the first time, 90 patients (24 women and 66 men), with occlusion in only 1 coronary artery participated in the study. Information regarding age, body mass index, sex, smoking, hypertension, diabetes mellitus, hyperlipidemia, preinfarction angina, and use of oral beta blockers and nitrates were recorded for all patients. The patients were separated into 2 groups in accordance with development of their coronary collateral circulation; those with insufficient (Rentrop 0, 1, and 2) and those with sufficient coronary collateral circulation. They were also divided into 3 groups on the basis of body mass index as follows: (I) 18.0-24.9 kg/m(2), (II) 25.0-29.9 kg/m(2), and (III) more than 30 kg/m(2). In the obesity and overweight groups, hyperlipidemia, diabetes mellitus, and nitrate use were identified more frequently than in the other groups (p < 0.05). Use of oral nitrates more than 6 months before the myocardial infarction and existence of preinfarction angina affected collateral coronary vessel development in the positive direction (p = 0.01, p = 0.03, respectively). There was no correlation between coronary artery disease and coronary collateral vessel development in the obese patients (p = 0.6). Although it has been shown that coronary collateral vessel development was affected negatively in obese patients with coronary artery disease, no statistical significance was identified.     

Plasma vascular endothelial growth factor level is elevated in patients with multivessel coronary artery disease

BACKGROUND: Vascular endothelial growth factor (VEGF) has been implicated in both angiogenesis and ischemia. However, the relationship between plasma VEGF level and coronary artery disease remains unknown. HYPOTHESIS: Plasma VEGF level may be associated with severe coronary artery disease and other cardiovascular risk factors. METHODS: We examined plasma VEGF concentration and coronary risk factors in 73 patients who underwent coronary angiography and 70 apparently healthy control subjects. According to the number of the three major coronary vessels with significant (> or = 75%) stenosis, we divided the patients into two groups: the mild stenosis group (0- and single-vessel disease, n = 36) and the severe stenosis group (double- and triple-vessel disease, n = 37). RESULTS: The log VEGF value of the severe stenosis group was significantly higher than that of the mild stenosis (p < 0.05) and control groups (p < 0.05). Furthermore, there was a significant positive trend in the log VEGF value according to the number of vessels with significant stenosis (p = 0.016). However, there was no significant difference in log VEGF value between the mild stenosis and control groups. Soluble vascular cellular adhesion molecule, soluble intracellular adhesion molecule, and other coronary risk factors were found to be associated with the presence of vessel stenosis. CONCLUSION: Unlike established coronary risk factors, the plasma VEGF level may be associated with only severe coronary ischemia such as multiple coronary vessel disease.