Subsequent Development Of Myocardial Infarction Research Articles

Association of Single Nucleotide Polymorphism of Apo A-1 Gene and Lipid Variables in Patients with Myocardial Infarction: A Case-control Study

Introduction: Genetic and environmental factors play a significant role in the development of cardiovascular disease (CVD). With advancements in molecular techniques, it is now possible to study genes that may provide evidence of the role of genetic factors in coronary artery disease (CAD). Genetic variants of the Apo A-1 gene might play an important role in regulating lipid profiles and their alteration, leading to the subsequent development of myocardial infarction (MI). Aim: The aim of this study was to evaluate the association between C+83T sequence variations in the first intron of the Apo A-1 gene and lipid variables in patients with MI. Materials and Methods: A case-control study was conducted at the Department of Biochemistry in association with the Department of Cardiology, Kilpauk Medical College Hospital, Chennai, Tamil Nadu, India, from October 2013 to March 2014. The study included 52 MI cases and 52 age-, gender-, and risk factor-matched controls. Fasting venous blood samples were collected from each patient, and routine investigations, lipid profile assessments, and polymorphic studies were carried out. Allele frequencies between cases and controls were compared using the Chi-square test. Analysis of variance (ANOVA) was performed to determine the association between fasting serum lipid variables and allele distribution. Results: Both study groups were matched for age, gender, and risk factors such as alcohol consumption, smoking, hypertension (HT), and diabetes mellitus (DM). The results were compared and found to be statistically insignificant. Genotype analysis between the groups disclosed that the TT homozygous genotype was more prevalent in cases, while the 'CC' genotype was more prevalent in controls, and the CT genotype was approximately equal in both cases and controls. The genotype difference between cases and controls was statistically significant (p-value=0.006). The 'T' allele frequency was higher among cases (0.36) compared to controls (0.13), while the frequency of the 'C' allele was higher among controls (0.86) compared to cases (0.63). In the CC genotype, there was a higher mean value of Apo A-1 and a lower ApoB/ Apo A-1 ratio compared to the TT genotype. It was observed that carriers of the C allele and T allele showed no statistical difference in lipid variables except for high-density lipoprotein (HDL). Conclusion: This study found a significantly increased T allele frequency in cases compared to controls, suggesting that the presence of the T allele in the C+83T (first intron) of the Apo A-1 gene may increase the risk of developing MI.

CLINICAL CASE OF ACUTE MYOCARDIAL INFARCTION IN PATIENTS WITH MICROVASCULAR ANGINA

Purpose. To describe a clinical case of coronary burden without stenosing lesions of the main branches of the coronary arteries in a patient with microvascular angina with subsequent development of myocardial infarction with the formation of ischemic hypokinesis of the anterior-apical region of the left ventricle in the absence of elevated levels of serum markers of myocardial necrosis.Materials and methods. The study is based on a single clinical case. The object of the study is the patient in whom there were complaints of pressing pain localized behind the sternum and radiating to the left arm, accompanied by a mixed shortness of breath that occurred at rest, poorly stoped short-range nitrates and narcotic analgesics, sharp General weakness. Under primary inspection state of ailing average extent of gravity, consciousness clear, position active, skin integuments and visible mucous of clean, conventional painting. The patient was evaluated laboratory parameters, ECG, echo-cardiography (ECHO-kg), chest x-ray (OGK), coronary angiography (CAG), followed by transfer to the emergency Department of cardiology.Results. The conducted clinical and laboratory study revealed the presence of leukocytosis in the patient with the clinic of acute coronary syndrome, without increasing cardiospecific enzymes (CFC, CFC-MB, troponin test), as well as high activity of coagulogram indicators (fibrinogen, ACTV, rfmc). When conducting radiography of OGK in direct projection-congestive lungs, a picture of chronic bronchitis in combination with left ventricular myocardial hypertrophy.Conclusion. In the presented clinical case was described an example of development of microvascular lesions in coronary arteries in a patient with manifestation of acute coronary syndrome with severe prolonged chest pain and repolarization changes on ECG and without elevated levels of serum markers of myocardial necrosis, which probably leads to the definition of this state as fragile (or sharp) microvascular dysfunction with myocardial infarction.

NEW PATHOGENETIC FACTORS OF ATHEROSCLEROSIS DEVELOPMENT AND POTENTIAL THERAPEUTIC APPROACHES

It has been demonstrated that one of the factors in the pathogenesis of atherosclerosis, with the subsequent development of myocardial infarction (MI), stroke (S), or sudden death (SD), is trimethylaminoxide (TMAO), the end-product of dietary choline, betaine, or carnitine metabolism by intestinal microflora. Simultaneously elevated levels of TMAO and carnitine are associated with a doubled or even tripled risk of MI, S, and SD. Therefore, dietary intake of choline-rich phosphatidylcholine fats and red meats and carnitine-rich dairy is an important risk factor (RF) of atherosclerosis. At the moment, there is no universally accepted therapeutic approach which reduces TMAO and carnitine levels. The only agent which can simultaneously reduce the levels of these two atherosclerosis-associated RFs is a well-known cardio- and cytoprotector Mildronate. Experimental and pilot clinical studies of Mildronate effectiveness in patients with obliterating atherosclerosis suggest the need for further, more detailed clinical trials of Mildronate, for estimation of its efficacy and safety.

Decreases in Electrocardiographic R-Wave Amplitude and QT Interval Predict Myocardial Ischemic Infarction in Rhesus Monkeys with Left Anterior Descending Artery Ligation

Clinical studies have demonstrated the predictive values of changes in electrocardiographic (ECG) parameters for the preexisting myocardial ischemic infarction. However, a simple and early predictor for the subsequent development of myocardial infarction during the ischemic phase is of significant value for the identification of ischemic patients at high risk. The present study was undertaken by using non-human primate model of myocardial ischemic infarction to fulfill this gap. Twenty male Rhesus monkeys at age of 2–3 years old were subjected to left anterior descending artery ligation. This ligation was performed at varying position along the artery so that it produced varying sizes of myocardial infarction at the late stage. The ECG recording was undertaken before the surgical procedure, at 2 h after the ligation, and 8 weeks after the surgery for each animal. The correlation of the changes in the ECG waves in the early or the late stage with the myocardial infarction size was analyzed. The R wave depression and the QT shortening in the early ischemic stage were found to have an inverse correlation with the myocardial infarction size. At the late stage, the R wave depression, the QT prolongation, the QRS score, and the ST segment elevation were all closely correlated with the developed infarction size. The poor R wave progression was identified at both the early ischemic and the late infarction stages. Therefore, the present study using non-human primate model of myocardial ischemic infarction identified the decreases in the R wave and the QT interval as early predictors of myocardial infarction. Validation of these parameters in clinical studies would greatly help identifying patients with myocardial ischemia at high risk for the subsequent development of myocardial infarction.

Pretransplant Cardiac Investigations in the Irish Renal Transplant Population—The Effectiveness of Our Current Screening Techniques in Predicting Cardiac Events

Background. Coronary artery disease (CAD) is prevalent among endstage renal failure patients and remains the major cause of mortality following renal transplantation. Death with a functioning transplant institute remains the most common cause of kidney graft failure. In this study we attempt to evaluate the effectiveness of the clinical history and current screening techniques available in predicting posttransplant CAD and also assess the role of coronary angiography as a pretransplant screening technique. Methods. Clinical data of 190 renal transplant patients was analyzed. Any clinical history of cardiac disease and all preoperative cardiac screening data was recorded for each patient. The study endpoints were the subsequent development of myocardial infarction (MI), undergoing coronary artery bypass graft (CABG) or death. Results. Factors that were significantly associated with reaching a study end‐point included: age at transplant [Hazard Ratio (HR) 1.91, P < 0.001], history of heart failure (HR 8.22, P < 0.001), presence of CAD on coronary angiography (HR 5.55, P = 0.033), anterior Q wave on electrocardiograph {ECG} (HR 8.6, P < 0.001), carotid artery disease (HR 3.74, P = 0.030) and history of a cerebrovascular accident (HR of 4.32, P = 0.008). The screening techniques of exercise stress testing and echocardiography were not conclusive as predictive variables of outcome. Conclusion. Clinical history and ECG results are good, practical and low‐cost screening methods. In our study exercise stress testing and echocardiography were found to be of limited value. Coronary angiography is appropriate in certain high‐risk groups but not necessary as part of screening in all potential renal transplant recipients.

Myocardial infarction in young patients with Hodgkin's disease ? potential pothogenic role of radiotherapy, chemotherapy, and splenectomy

Among a total of 2147 patients admitted to our hospital for acute myocardial infarction between 1978 and 1987, three young patients aged 24, 29, and 39 years had previously been treated for Hodgkin's disease. Staging laparotomy, including splenectomy, had been performed in all three patients. Two patients had both mediastinal irradiation (21 and 27 months before infarction) and chemotherapy. In the first patient, postmortem histologic examination of the coronary arteries revealed fibrotic changes, which were probably induced by radiotherapy. In our second patient, myocardial infarction developed 5 days after vinblastine treatment; early angiography showed thrombotic occlusion of the proximal right coronary artery, which was recanalized using the diagnostic Sones catheter. Subsequent angiography revealed normal coronary arteries. This is, to our knowledge, the first case of documented coronary artery thrombosis after treatment with vinca-alkaloids. In our third patient, neither mediastinal irradiation nor chemotherapy had been performed prior to myocardial infarction. However, a marked increase in platelet counts following splenectomy was observed in this patient. The role of radiotherapy, chemotherapy, and splenectomy with consecutive thrombocytosis as a third possible pathogenic factor for subsequent development of myocardial infarction is discussed.

Plasma HMW fibrinogen in patients with ischaemic heart disease

Fibrinogen has been reported to be a risk factor for development of myocardial infarction in patients with ischaemic heart disease. The functional properties of plasma high molecular weight (HMW) fibrinogen would suggest that this fibrinogen species is responsible for the association. In a prospective study with a follow-up period of 6 years the plasma concentrations of clottable fibrinogen and of HMW fibrinogen were related to the subsequent development of myocardial infarction in 53 patients admitted with ischaemic heart disease. Neither the concentrations of clottable fibrinogen nor of HMW fibrinogen in the 25 patients developing myocardial infarction deviated from the concentrations in the 28 patients with an uncomplicated course. A significant positive correlation between the concentrations of clottable fibrinogen and of HMW fibrinogen (rs = 0.58, p less than 0.001) suggests that HMW fibrinogen represents a major fraction of the clottable fibrinogen concentration in patients with ischaemic heart disease.

Epiphenomenology and the gallbladder: Several examples

It has been suggested that gallbladder removal may protect against subsequent development of myocardial infarction because of increased gastrointestinal cholesterol excretion resulting from increased enterohepatic cycling. To test this hypothesis, the authors used data from two large case-control studies of myocardial infarction--one conducted in 1976-1979 in 155 US hospitals and one conducted in 1980-1983 in 78 US hospitals. First, 550 female myocardial infarction cases were compared to 1,658 controls. Simultaneously adjusting for possible confounding variables using logistic regression, the odds ratio for development of a myocardial infarction subsequent to cholecystectomy was 0.8 (95% confidence interval, 0.5-1.1). Second, 1,511 male myocardial infarction cases were compared to 3,837 controls. With similar adjustments, the odds ratio was 0.8 (95% confidence interval, 0.5-1.2). The risk did not decline as the interval following cholecystectomy increased. The present data are compatible with a protective effect of cholecystectomy on the risk of subsequent myocardial infarction, but they are not conclusive. This study was undertaken to assess possible modifications of the proliferative activity of co-Ionic mucosa, which could be related to a suggested cancer-promoting role of cholecystectomy. The mitotic index (number of mitoses per 1000 gland cells) was evaluated in the colonic mucosa of 14 healthy subjects, 11 patients with cholelithiasis, before and 6 months after surgery, and 10 patients who had undergone cholecystectomy 2 or more years previously. The mitotic index of cholecystectomized patients was significantly higher than controls. It rose significantly within 6 months of cholecystectomy. The mitotic index of patients with cholelithiasis before surgery was similar to controls. These data suggest that cholecystectomy is followed by an enhancement in the proliferative activity of the colonic mucosa, which could play a cancer-promoting role.

Does gallbladder removal protect against subsequent myocardial infarction?

It has been suggested that gallbladder removal may protect against subsequent development of myocardial infarction because of increased gastrointestinal cholesterol excretion resulting from increased enterohepatic cycling. To test this hypothesis, the authors used data from two large case-control studies of myocardial infarction--one conducted in 1976-1979 in 155 US hospitals and one conducted in 1980-1983 in 78 US hospitals. First, 550 female myocardial infarction cases were compared to 1,658 controls. Simultaneously adjusting for possible confounding variables using logistic regression, the odds ratio for development of a myocardial infarction subsequent to cholecystectomy was 0.8 (95% confidence interval, 0.5-1.1). Second, 1,511 male myocardial infarction cases were compared to 3,837 controls. With similar adjustments, the odds ratio was 0.8 (95% confidence interval, 0.5-1.2). The risk did not decline as the interval following cholecystectomy increased. The present data are compatible with a protective effect of cholecystectomy on the risk of subsequent myocardial infarction, but they are not conclusive.

Studies on Clinical Prediction of Myocardial Infarction

Myocardial infarction frequently occurs suddenly, and the prediction of its onset is said to be difficult. However, concept of coronary risk factors have drawn attention through epidemiological studies on ischemic heart disease. Since anginal pain is frequently experienced prior to the attack of myocardial infarction, pursuit of coronary risk factors and angina pectoris makes prediction of myocardial infarction possible to Results and Discussion some extent. Materials and Methods In 11, 188 cases of ambulant and hospitalized patients and subjects admitted for examination, follow-up studies by questionaires and direct examination were carried out. Prognosis was established in 3, 851 cases. 2621 cases of these after exclusion of young subjests below the age of 30 and insufficiently examined subjects, and 110 cases observed from pre-attack period in other institutions, a total of 2, 731 cases, were employed in this study. They were subdivided in following three groups: group of 265 cases of myocardial infarction (MI) (208 males and 57 females), group of 215 cases of angina pectoris (AP) (132 males and 83 females) and group of 2, 251 cases of control subjects (CS) (1 .253 males and 998 females). In MI group, 165 cases (132 males and 33 females) had experienced anginal attack prior to (MIA), AP group consisted of the patients of angina pectoris without subsequent development of myocardial infarction for at least one year of follow-up period. Coronary risk factors were compared among MI group, AP group and CS group. Moreover, these factors and clinical course of angina pectoris were also compared between AP group and MIA group. There were little difference in average age among these groups.