View clinical trials related to Coronary Disease.
Filter by:The initial manifestation of symptomatic coronary disease can range from angina (or symptoms of angina), unheralded acute coronary syndrome (ACS), or unheralded coronary death. A better understanding of gender differences in initial presentation of coronary disease and the rate and predictors of progression to subsequent stages in coronary disease could help to identify which gender- specific factors might reduce or slow transition to more serious disease states and improve outcomes. The investigators' research focuses on the role primary care management of cardiovascular risk factors plays in gender differences in the progression to subsequent disease states and to mortality.
Coenzyme Q10 (Ubiquinone) is recognized as an endogenous fat-soluble antioxidant in the mitochondrial membrane and considered as a preventive factor for coronary artery disease (CAD). However, the relationships between coenzyme Q10 and the prevention of the risk of CAD are still inconsistent. The purposes of this study are to investigate the relation of coenzyme Q10 concentration with the blood lipid levels, plasma homocysteine, the markers of lipid peroxidation (TBARS, ox-LDL),antioxidant enzymes activities (catalase, glutathione peroxidase, superoxide dismutase)and to examine the association with the risk of CAD.The CAD patients is identified by cardiac catheterization as having at least 50% stenosis of one major coronary artery (n = 100). The second year is a double-blind, placebo-controlled intervention study. CAD subjects (n = 60) are randomly assign to one of the three groups (coenzyme Q10 supplements 60 mg/d, 150 mg/d, and placebo groups, n = 20/group). Intervention is going to administration for three months. The third year is a case-control study. The control group （n = 100） is comprised of healthy individuals with normal blood biochemical values, and match by age and gender with the first year CAD subjects (case group). Fasting blood samples will be obtain to determine the concentration of coenzyme Q10, homocysteine, the markers of lipid peroxidation,antioxidant enzymes activities. The differences between case and control groups will be compared by using Student's t-test. Conditional logistical regression model will be performed to calculate the odds ratio for CAD based on coenzyme Q10 level. Hopefully, the results of this study could provide the information to what has been know in CAD subjects. We expect coenzyme Q10 could be a preventive supplement to reduce the risk of CAD.
Telemedicine has been widely used in managing patients with neurologic disorders or mental illness. Telemedicine is defined as the use of medical information exchanged from one site to another via electronic communications for the health and education of the patient or healthcare provider and for the purpose of improving patient care. According to our knowledge, it has not been used to manage cardiac patients who need postoperative care after discharge from hospitals. The use of telemedicine has the potential to reduce the cost of unnecessary travel by assessing the patient's postoperative status prior to making decisions as to whether or not a face-to-face consultation is necessary. In this pilot study we will compare the accuracy of surgeons' decisions during follow-up visits via video-teleconference (V-Visit) to surgeons' decisions during traditional face-to-face follow-up visits (FTF-Visits). Both the V-Visit and the FTF-Visit will take place at the Houston Michael E DeBakey VA Medical Center on the same day. We will also ask both patients and providers to complete short questionnaires after each V-Visit regarding their acceptability of using telemedicine for these post-operative follow-up visits. Information collected as part of this pilot study will be used to design a future full randomized controlled trial (RCT) on the use of telemedicine in evaluating post-operative cardiac surgical patients.
Background: Chest pain (CP) and suspected heart attack is the second most frequent complaint among patients presenting to the emergency department (ED). Present workup involves in-hospital observation for 6 - 48 hours and requires significant resources including imaging tests, some of which are invasive and involve radiation and radio-contrast agents, which can be toxic to the kidney. CP can result from impaired blood supply to the heart muscle, which may result in impaired contraction of the heart that persists for several days. Bedside echocardiography with semi-automated speckle tracking strain analysis (2D strain) is a novel promising noninvasive tool for the evaluation of heart muscle contraction. 2D strain can be useful for evaluating patients with CP, since it can accurately detect minor impairment in heart muscle contraction that can identify patients with coronary artery disease (CAD) and impending heart attack (coronary arteries are the arteries supplying blood to the heart muscle). Working hypothesis and aims: The investigators hypothesize that a bedside echo study with normal 2D strain may allow quick and safe ruling out of a heart attack and significant CAD disease as the cause of CP. The main aim of the study is to validate the investigators preliminary findings in a large number of patients in order to establish whether a normal 2D strain can safely rule out a heart attack or life threatening CAD. Methods: In a large multi-center study 1200 patients presenting to the ED with acute CP of an unclear cause will undergo echocardiography as close as possible to presentation and not more than 24 hours from cessation of pain. Patients will undergo standard workup by the ED physicians. Standard echocardiographic findings, but not the 2D strain analysis, will be made available to the attending physician. Data from discharge letters, ECGs, blood tests, stress tests, nuclear imaging, heart CT and heart catheterization will be collected. A 6-month follow-up telephone interview will be performed to collect data on survival, heart attacks, re-hospitalization and revascularization (opening heart vessels blockages). 2D strain analysis will be performed off-line in a central laboratory to evaluate the ability of 2D strain to distinguish between patients with CP from heart disease and patients without life threatening heart disease that can be early released home safely. Expected results: The investigators expect, based on the investigators previous experience, that patients with normal 2D strain will have a very low probability of a heart attack and significant CAD. The investigators further expect these patients to have an excellent 6-month prognosis. This will allow their early and cost-effective discharge. Importance and Probable implications to Medicine: Reduction in ED patient load and a decrease in unnecessary hospitalizations for CP. Cost and resource savings and elimination of unnecessary imaging studies, some of which are invasive or involve radiation and contrast agents.
The purpose of this study is to determine if regadenoson is as safe and effective as adenosine when used in the cardiac catheterization lab during measurement of coronary flow reserve and fractional flow reserve. The study hypothesis is the assessment of Fractional Flow Reserve (FFR) in the catheterization lab can be performed with equivalent accuracy when hyperemia is induced with IV Regadenoson compared with IV Adenosine without compromising patient safety.
Reactive platelet hyperactivity following coronary artery bypass grafting (CABG) might lead to thrombotic complications and major ischemic cardiac events. The aim of this study is to evaluate the changes in platelet reactivity following CABG and to clarify a potentially beneficial effect of dual antiplatelet therapy in the group of patients with documented aspirin resistance following CABG. Platelet function will be assessed by multiple electrode aggregometry. Aortocoronary vein graft disease is comprised of three distinct but interrelated pathological processes: thrombosis, intimal hyperplasia and atherosclerosis. Early vein thrombosis is a major cause of vein graft attrition during the first month after CABG. Bypass patency can be improved with antiplatelet therapy which is the mainstay of treatment for patients after CABG. A beneficial effect of acetylsalicylic acid (ASA) on vein graft patency has been previously shown. Some patients experience thrombotic events despite continuous aspirin administration after CABG. The investigators hypothesized that low responsiveness to aspirin might be a precipitating factor for adverse thrombotic events following CABG. Low responsiveness to ASA, as assessed by platelet function tests, varies widely among patients. The etiology of postoperative platelet hyperactivity remains to be elucidated. In this study a new point-of-care assay named multiple electrode aggregometry (MEA) using a device called Multiplate analyzer (Dynabyte, Munich, Germany) has been utilized. It allows for rapid and standardized assessment of platelet function parameters. This is a prospective randomized trial. The aim of the study is to document whether introduction of dual antiplatelet therapy in patients with ASA resistance will lead to a lower incidence of major adverse cardiac events (MACE) at a six month follow up. The composite endpoint will include death, non-fatal myocardial infarction, stroke and cardiac rehospitalization. All patients will receive 300 mg of ASA starting 6 hours after surgery, provided that the chest tube output is minimal. On postoperative day 4 their platelet function will be assessed using the above mentioned MEA. The patients found to be aspirin resistant will then undergo the process of randomization. The first arm will include patients with ASA resistance in whom no additional antiaggregation will be administered. In the second arm the investigators will include patients who were randomized to receive 75 mg of clopidogrel in addition to the standard antiplatelet regimen of 300 mg of ASA. Platelet function monitoring allows for individual tailoring of the antiplatelet therapy. The goal of this study is to define whether this strategy will lead to improved patient outcomes. Both major and minor bleeding complications will be strictly monitored and reported.
Elective percutaneous coronary intervention (PCI) is associated with troponin release in approximately one third of cases. Myocardial necrosis may result from downstream embolization of atheromatous material, coronary side-branch occlusion and may involve ischemia/reperfusion injury. The investigators hypothesized that a single remote ischemic preconditioning cycle would reduce peri-procedural troponin release.
The present prospective, multicenter study will therefore be performed with the primary objective of establishing the correlation between fractional flow reserve (FFR) and intravascular ultrasound with virtual histology (VH-IVUS)-derived parameters in angiographically intermediate coronary lesions. The current study will also examine the relative prognostic utility of FFR and VH-IVUS as a tool to defer percutaneous coronary intervention (PCI), by assessing the long-term rate (up to 3 years) of lesion-related clinical events if deferred by FFR vs. VH-IVUS versus not deferred PCI.
This is a multi-center, prospective registry of patients with intermediate coronary lesions defined as a stenosis of 40-80% by angiography. Approximately 300 patients will be enrolled into the study at sites in the United States and Europe. There will be no follow up beyond hospital discharge in this study. A sub-group of 30 patients will undergo Adenosine MRI. The investigators hypothesize that Intravascular Ultrasound Radiofrequency (IVUS RF) anatomical criteria, such as minimal luminal area, plaque burden and virtual histology plaque type, can predict physiological ischemia by Fractional Flow Reserve (FFR).
The primary objective of the study is to see if coronary artery calcium score and computed tomography coronary angiogram alters the proportion of patients diagnosed with angina due to coronary heart disease.