Causation Of Coronary Artery Disease Research Articles

PRESENCE OF LOW VITAMIN D AND HIGH SERUM LIPOPROTEIN 'A' LEVELS IN CAD: DO THEY IMPART RISK IN SYNERGISM?

Aims: Coronary artery disease (CAD) is an inflammatory disorder. Recently low vitamin D and high lipoprotein ‘a’ (Lp‘a’) have been linked in causation of coronary artery disease. This study was conducted to see the the combined effect of these two modifiable risk factors i.e. low vitamin D and high Lp‘a’ in etiology of CAD. Methods: It was a cross sectional study. Triple vessel disease patients (n=31) admitted for bypass surgery were taken as cases and age and gender matched healthy persons were taken as controls (n=30). Serum vitamin D estimation was done by competitive ELISA method. Serum Lp‘a’ estimation was done by immunoturbidimetric assay. Results: when subjects were compared for dual risk factor (Vitamin D deficiency and Hyperlipoproteinemia‘a’), it was observed that the odds of having disease were very high (OR=30.00; p=0.0004) than the single risk factor (OR for Hypovitaminosis D = 3.33; p=0.03 and OR for Hyperlipoproteinemia ‘a’ = 5.00; p=0.004). The Pearson’s correlation coefficient for the relationship between serum Vitamin D and Lipoprotein ‘a’ shows no correlation (r = ̶ 0.1019). Conclusion: Risk of having CAD increases many folds when subject has vitamin D deficiecy as well as high Lp‘a’.

Role of Lipids in type 2 diabetes mellitus for causation of coronary artery disease

Diabetes is characterized by chronic hyperglycemia and disturbances of carbohydrate, protein and lipid metabolism. The present study was undertaken to research the association between serum lipid profile, its abnormalities and the increase risk of coronary artery disease. The study compromised of total 60 subjects out of which 30 were diabetic pateints with T2D and 30 healthy indiviuals, both from the age group 35-50 years. The results indicated that there was a considerable increase in the lipid and its parameters. Keywords: Diabetes mellitus, HDL-c, LDL-c, Lipid profile, Total cholesterol, VLDL-c.

Current Concepts in Management of Lipid Abnormalities in Patients With Coronary Artery Disease

Lipid disorders play a major pathogenic role in the development of coronary artery disease, which is the major cause of mortality worldwide. In this review, the authors discuss the role of various lipid abnormalities in the causation of coronary artery disease and also highlight the ways to manage them. The roles of a healthy lifestyle and dietary patterns have been emphasized in this regard besides the significant role of drug treatment, which mostly revolves around the statin therapy.

Relationship between Body Iron Status and Cardiovascular Risk Factors in Patients with Coronary Artery Disease

Background: Iron is an essential trace element. It has a pivotal role in maintaining various cellular functions and enzyme reactions; whereas, iron overload has been known as a risk factor in progression of atherosclerosis. Objectives: The aim of this study was to investigate the role of the serum iron, serum ferritin and total iron binding capacity (TIBC) in the causation of coronary artery disease (CAD) and their relationship with other risk factors of CAD. Material and Methods: The study group consisted of 40 angiographically confirmed cases of CAD and 40 healthy controls. Serum lipids, serum lipoproteins, serum iron and TIBC were estimated by autoanalyzer (Dxc 900 Beckman coulter). Serum ferritin was measured on Mini VIDAS and malondialdehyde (MDA) was being done by Thiobarbituric acid method. Results: Significant difference was found among the controls and CAD patients regarding the occurrence of weight, height, BMI, Hip circumference and Waist circumference and FBS. The ratio of Total cholesterol and HDL was significantly raised in CAD patients (4.80) than controls (3.48). Serum iron and Serum ferritin levels were significantly elevated in patients with CAD when compared with control groups (118.2 ± 22.7mg/dl versus 105 ± 19.6mg/dl, p Conclusion: Study concluded that increased levels of serum iron, ferritin might consider as risk factor for CAD in conjunction with other risk factors. Key words: CAD, Ferritin, Iron, MDA,TIBC.

PROFILE OF CONVENTIONAL RISK FACTORS IN PATIENTS PRESENTING FOR CORONARY ANGIOGRAPHY IN A TERTIARY CARE HOSPITAL

ABSTRACT: Introduction: The conventional risk factors for coronary artery disease (CAD) include hypertension, diabetes mellitus, hyperlipidaemia and cigarette smoking(1). There is a large body of evidence, which implicates these factors in the causation of coronary artery disease. Objective: To study the pattern of the above-mentioned as well as additional risk factors including age, gender, family history, obesity and hepatitis B and C seropositivity in the population of patients undergoing coronary angiography at our tertiary care hospital. Methodology: In this cross-sectional survey, 465 patients undergoing coronary angiography were studied using a questionnaire as well as clinical and laboratory data. The information obtained included age, sex, clinical presentation, past medical history, family history, the presence or absence of previous ischemic heart disease, diabetes, hypertension and a history of smoking. A history of duration of diabetes and hypertension, their treatment and the presence or absence of complications was also noted. A proportion of patients had their fasting blood lipid levels measured. Height, weight and waist circumference as well as HepBsAg and anti-HCV levels were also determined. Results: The 465 patients studied included 383 males and 82 females. The mean age of all patients was 49.68 ± 0.464 years and the difference between genders was not significant. A past history of ischaemic heart disease was present in 31% of patients. Diabetes mellitus was present in 23% of males and 45% of females. A history of hypertension was present in 30.8% males and 70.7% of the females. Of the patients who could be studied, the mean LDL was 110.29 ± 1.706 mg/dL, the mean HDL was 41.01 ± 0.319 mg/dL and the mean TG was 189.67 ± 4.21 mg/dL. The difference in lipid profile values between male and female patients was not significant (p-value >0.05). Waist circumference was increased in 69.7% males and 93.9% females and here the difference between genders was significant ,HepBsAg alone was present in 3.9% patients and together with anti-HCV in 1.1% patients. Anti-HCV antibodies alone were present in 10.5% of patients. In all, almost 90% patients had at least one of the conventional risk factors. Conclusion: This study shows that conventional risk factors for ischaemic heart disease are present to a significant degree in our population of patients in whom coronary angiography is considered necessary, and should be targeted for prevention and control. Key words: Coronary heart disease, conventional risk factors, hypertension, diabetes, coronary angiography.

Promoter variants in interleukin-6 and tumor necrosis factor alpha and risk of coronary artery disease in a population from Western India

INTRODUCTION:A central component of the atherosclerotic process is inflammation. Single nucleotide polymorphisms (SNPs) present in the promoter region of various cytokines can lead to altered levels of the transcript and a state of low-grade inflammation exacerbating the risk of coronary artery disease (CAD). The present work tries to understand the role of permissive promoter variants in the interleukin-6 gene (IL-6-174G/C) and the tumor necrosis factor alpha (TNFα-308G/A) in the causation of CAD and also dyslipidemia.MATERIALS AND METHODS:Genotyping was conducted on 100 cases of CAD and 150 controls by the allele termination assay SNaPshot. Biochemical parameters were determined by routine enzymatic endpoint methods. The results were analyzed by appropriate statistical methods.RESULTS:No differences in the minor allele frequency IL-6-174G/C SNP were seen between cases and controls (0.13 vs. 0.12). The differences in the allele frequency of TNFα-308A between cases (6%) and controls (2%) have led to an odds ratio, 3.370; 95% confidence interval, 1.039-11.543; P=0.033 in the univariate analysis. In the final logistic regression analysis, however none of the variants were associated with an increased risk of CAD.CONCLUSIONS:In summary, no association of the permissive promoter variants in the IL-6 gene and the TNFα gene were seen with an increased CAD risk. These and other studies highlight the importance of doing population specific studies.

Apo E polymorphism among Egyptian patients with essential hypertension

Hypertension (HTN) is a chronic condition of concern due to its role in the causation of coronary artery disease (CAD), stroke, and other vascular complications. Essential hypertension (EH) is a multifactorial disorder arising from the influence of several susceptibility genes and environmental stimuli. Apolipoprotein E (Apo E) plays an essential role in clearance of chylomicron remnants and very low-density lipoproteins (VLDL). Apo E gene has three alleles (E2, E3, and E4) that give rise to six different genotypes. A significant association of E4 allele has been observed with HTN in addition to the other well-known risk factors and positive family history. Carriers of E4 allele form a higher risk group showing greater susceptibility to CAD. These observations emphasize the need of genotyping Apo E in patients with EH as an important molecular tool in personalized medicine. The aim of this work was to study the association between Apo E gene polymorphism and EH in Egyptian patients as well as correlating different Apo E genotypes with serum lipids. The study was conducted on 50 patients with EH and 50 age-matched controls. DNA analysis was performed using polymerase chain reaction restriction fragment length polymorphism. The E3/E3 genotype was found in 85.42 % of patients, compared to 80 % in controls. E3/E4 (8.33 %) and E2/E3 (6.25 %) were lower in patients compared to controls 12 and 8 %, respectively. E4/E4 and E2/E2 genotypes were only found in two patients (4 %). Total cholesterol and low-density lipoprotein were significantly higher in E3/E4 as compared to E3/E3 and E2/E3. However, there was no significant difference in triglyceride, high-density lipoprotein, and VLDL.

Hepatitis C Virus (HCV) “A Possible Independent Risk Factor†for Coronary Artery Disease

Background: HCV seropositivity has been linked to the presence of coronary artery disease (CAD).1 It is reported that HCV infection accelerates atherosclerosis.2-4 Controversy persists regarding the extent of independent or shared role of HCV infec-tion in the causation of CAD. Therefore we carried out this study to detect the prevalence of CAD among patients with HCV seropositivity. Objective: To validate the Hypothesis weather HCV seropositivity is associated with CAD or not. Study Design: Cross – Sectional Analytical type with consecutive sampling of patients with seropositivity for Anti – HCV antibodies. Who were diagnosed just before cardiac catheterization. Study Place and Period: It was carried out at the department of Cardiology of Mayo Hospital Lahore from January 2006 to December 2008. Patients and Methods: A total of 273 HCV seropositive patients were in the study group and 195 HCV negative who were age matched and had similar clinical presentation and were admitted at the same institution. All HCV positive patients were confirmed on Eliza. Coronary Angiography was done in all patients. Results: Mean age of HCV+ patients was 49.388 ± 12.23 years and HCV- patients was 49.26 ± 9.45 years. In HCV+ patients who presented with chest pain, the prevalence of CAD was almost 91% while in HCV- group it was 78.46%. Conclusion: Our study has shown an unambiguous and clear association between HCV infection and complex CAD. How-ever these results need to be confirmed in further longitudinal studies. Key Words: HCV (Hepatitis C – Virus), CHD (Coronary Heart Disease), CAD (Coronary Artery Disease), DM – 2 (Dia-betes Mellitus Type – 2), ACS (Acute Coronary Syndrome).

A Review on Traditional Risk Factors and Coronary Angiographic Findings between Younger and Older patients of Coronary Heart disease

Ischemic heart disease (IHD) or Coronary Heart Disease (CHD) is a generic designation for a group of closely related syndromes resulting from myocardial ischemia. It comprises of stable angina, unstable angina, acute myocardial infarction and sudden death. Since the most common cause of IHD is coronary artery as a plaque of atheromatous deposits. It is often accompanied by atheromatous manifestations elsewhere in the body.It is a major cause of morbidity and mortality in the developed countries and its prevalence is rising in the developing countries. Though its prevalence is higher in developed countries, it has gained considerable attention in developing countries due to its rising trend and change in life style of the urban population. Association of risk factors with causation of coronary artery disease in young population also appears to be stronger.Compared to elderly. This is true particularly with regards to certain specific risk factors like BMI, Raised BP, LDL, TG and smoking.It is a pathological entity characterized by presence of intimal lesions called fibrofatty streaks or atheromas which protrude into and obstruct the vascular lumen. When it occurs, it involves almost every vascular bed and can produce myriads of manifestations of which Coronary artery disease is the most clinically significant. It starts at an early age as fatty streaks and then evolves into more complex atheromatous and fibro atheromatous lesion.Atherosclerosis leading to Coronary Heart Disease (CHD) is complex in origin. Involved in the pathogenesis of atherosclerosis are hemodynamic, throombotic, carbohydrate- lipid metabolic variables along with intrinsic characterization of arterial wall. These physiologic and biochemical factors underlie the clinical events that may eventually occur. Environmental factors such as smoking and sedentary life style also contribute to this process. The progression of atherosclerotic disease and increasing severity of atherosclerosis risk factors but also to the persistence of risk factors over time.Premature Coronary Artery Disease (CAD) is defined as CAD occurring below 65 years in women and 55 years in men. CAD in young is defined as CAD occurring in patient University Heart Journal Vol.4(1) January 2008

Correlation Between C677T MTHFR Gene Polymorphism, Plasma Homocysteine Levels and the Incidence of CAD

The lesions of coronary atherosclerosis represent the result of a complex, multicellular, inflammatory-healing response in the coronary arterial wall. In vivo and in vitro cellular and molecular studies have suggested a role for tissue homocysteine in endothelial cell injury and adverse extra-cellular matrix remodeling. Gene polymorphisms in relation with numerous risk factors might increase the incidence of coronary artery disease (CAD). In this review we have focused on the correlations between plasma homocysteine levels, the incidence of cardiovascular disease and the cytosine-to-thymidine substitution at nucleotide 677 (C677T) of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, coding for a key enzyme in methionine-homocysteine metabolism. The role of the C677T MTHFR gene polymorphism in the causation of CAD is controversial. We reviewed 12 recent case-control studies comprising 5370 genotyped patients with CAD and 4961 genotyped participants without CAD. There was no significant difference between those with and without CAD in the frequency of the C677T polymorphism (34.9 vs 33.6%). The frequency of homozygous C677T polymorphism in these groups was 10.9 versus 12.8%, respectively, although there were some ethnic differences in the C677T MTHFR polymorphism. In the analysis of the 12 studies, the odds ratio of CAD associated with the TT genotype (homozygous C677T polymorphism) was 1.18. Only slightly higher plasma homocysteine levels were observed in participants with the val/val (TT) genotype (14.4+/-2.9 micro mol/L in TT genotype vs 11.1+/-1.9 and 11.9+/-2 micro mol/L in CC and CT genotype, respectively). In addition, the relation between homocysteine increase after methionine loading and MTHFR genotypes is also controversial. However, hyperhomocysteinemia because of the C677T MTHFR allele may be corrected with oral folic acid therapy. Further investigations on the relationships between MTHFR genotypes and the incidence of CAD should be based on larger samples, paying attention to the differences between various ethnic populations. Individual therapeutic strategies based on single nucleotide polymorphism may become increasingly important for preventive treatment against polygenic CAD.

Hypertriglyceridemia, Atherogenic Dyslipidemia, and the Metabolic Syndrome

The importance of high serum cholesterol, especially a high level of low-density lipoprotein (LDL) cholesterol, as a risk factor for coronary artery disease is well established. Likewise, efficacy for decreasing risk for coronary artery disease by LDL-lowering therapy has recently been documented through clinical trials. However, many high-risk patients manifest elevated serum triglyceride levels, and the role of hypertriglyceridemia in causation of coronary artery disease remains to be elucidated. Nonetheless, there is growing evidence that hypertriglyceridemia is a marker for increased risk for coronary artery disease; in fact, it can serve as a marker for several atherogenic factors. These factors include increased concentrations of atherogenic triglyceride-rich lipoproteins; the atherogenic lipoprotein phenotype, or lipid triad; and the metabolic syndrome. The lipid triad consists of elevated serum triglycerides, small LDL particles, and low high-density lipoprotein (HDL) cholesterol. The metabolic syndrome includes the coexistence of the lipid triad, elevated blood pressure, insulin resistance (plus glucose intolerance), and a prothrombotic state. Many previous studies indicate that hypertriglyceridemia is strongly associated with all of these atherogenic factors. The clinical approach to treatment of patients with hypertriglyceridemia thus requires a broad-based strategy that includes reduction of atherogenic triglyceride-rich lipoproteins, reversal of the lipid triad, and favorable modification of the metabolic syndrome. The development of therapeutic regimens to effect these changes poses a challenge for future research on the problem of hypertriglyceridemia.

Treatment of dyslipidemia in non-insulin-dependent diabetes mellitus with lovastatin

Coronary artery disease (CAD) is the leading cause of death among whites with non-insulin-dependent diabetes mellitus (NIDDM). Several risk factors—dyslipidemia induced by NIDDM, obesity, hypertension and hyperglycemia—likely contribute to accelerated atherosclerosis. The dyslipidemia in NIDDM is characterized by abnormalities in composition and metabolism of very low density lipoproteins, low-density lipoproteins (LDL) and high-density lipoproteins (HDL). However, because of the lack of long-term prospective epidemiologic studies, the relative importance of lipoprotein risk factors in the causation of CAD in diabetic patients is not clear. The World Health Organization Multinational Study of vascular disease in diabetics observed increased prevalence of CAD in diabetic populations with relatively high levels of plasma cholesterol and supports the concept that lowering cholesterol levels may significantly reduce coronary risk in NIDDM. To determine the effectiveness of lovastatin, an inhibitor of HMG CoA reductase, for lowering cholesterol levels, 16 patients with NIDDM and mild to moderate increases in plasma cholesterol were given lovastatin (20 mg twice daily) in a randomized, double-blind, placebo-controlled manner for 4 weeks. Compared with the placebo, lovastatin reduced concentrations of total cholesterol (233 ± 10 vs 172 ± 7 mg/dl [standard error of the mean], p < 0.001), LDL cholesterol (140 ± 9 vs 101 ± 6 mg/dl, p < 0.001), and LDL apolipoprotein-B (108 ± 16 vs 80 ± 16 mg/dl, p < 0.001). Plasma triglycerides and very low density lipoprotein cholesterol levels also decreased by 31 and 42%, respectively. Although HDL cholesterol levels did not increase, the total cholesterol/HDL cholesterol ratio decreased significantly with lovastatin therapy. No adverse effects were noted and glycemic control was well-maintained. If HMG CoA reductase inhibitors such as lovastatin continue to be devoid of serious toxicity, they could reduce the prevalence of CAD in NIDDM.

The role of unnatural dietary trans and cis unsaturated fatty acids in the epidemiology of coronary artery disease

During 1956 the first report on the hypocholesterolemic effect of unsaturated fatty acids of plant and marine origin was published in The Lancet. Consequently it was stated in a Lancet Editorial that hydrogenation of vegetable oils could have contributed to the causation of coronary artery disease and predicted that a decade would probably be required to resolve this question. However, after the lapse of three decades this issue would appear to be no nearer to a clear answer now than it was then. During 1956 hydrogenation was assumed to effect only a reduction in the level of unsaturated fatty acids in the products produced from hydrogenated oils. However, since that time essential fatty acid metabolic pathways to eicosanoids were discovered and described. Also large quantities of unnatural trans and cis unsaturated fatty acids have been shown to form during hydrogenation and these occur in margarines and many other common foods in high concentrations. It has also been shown that these unnatural trans and cis fatty acids block essential fatty acid metabolism by the competitive inhibition of the desaturase enzyme Δ-6-desaturase. Therefore some of the possible metabolic mechanisms whereby “hydrogenation plants could have contributed to the causation of a major disease” have become clearer during the last three decades. Despite a recent conclusion by an ad hoc FDA panel that there need be little concern about the effects of trans fatty acids in the American diet on health, it is nevertheless proposed that on the basis of available evidence, unnatural dietary trans and cis unsaturated fatty acid isomers should be regarded as a definite risk factor in the etiology of coronary artery disease.