Active clinical trials for "Myocardial Ischemia"

Prasugrel is a potent thienopyridine antiplatelet agent that selectively and irreversibly inhibits ADP-induced platelet aggregation mediated by the P2Y12 receptor. Prasugrel is a prodrug that must first undergo biotransformation to its active metabolite via cytochrome P450-mediated hepatic metabolism (CYP1A2). Clopidogrel is currently administered to several million patients especially after coronary stenting. Clopidogrel has been shown to reduce cardiovascular complications in patients with acute coronary syndromes and patients who have undergone coronary stenting. The mechanism of action of clopidogrel's active metabolite involves inhibition of the purinergic adenosine diphosphate (ADP) receptor P2Y12 on the platelet membrane. Blockade of this receptor prevents uncoupling of the associated Gi2 protein which ultimately leads to increased platelet cyclic AMP (cAMP) formation.3 Cyclic AMP is a key signaling molecule in inhibiting platelet aggregation, but its intracellular levels are affected by several other commonly used compounds. For instance, methylxanthines, such as caffeine, theophylline, and theobromine (an ingredient of chocolate), all cause elevation of intracellular cAMP levels by inhibiting adenosine receptors (types A1 and A2) on the platelet membrane. The effect of caffeine consumption on platelet reactivity depends on the caffeine dose and duration of administration. Chronic caffeine consumption (≥7 days) appears to be associated with inhibition of platelet aggregation, probably through upregulation of adenosine receptors.The aim of this study was to examine the effect of acute caffeine consumption, at a dose equivalent to commercial coffee drinks, on the antiplatelet effect of clopidogrel and prasugrel, in patients with coronary artery disease (CAD). Platelet function will be evaluated using a validated method: the VerifyNow System (Accumetrics Inc., San Diego, CA), which is a point-of-care turbidimetry-based optical detection system that measures platelet-induced aggregation.

To show the existence of a atrial cardiomyocytes membranes modification in omega-3 supplemented patients with coronary atherosclerosis.

The purpose of this study is to evaluate the efficacy and tolerance of a dipyridamole/adenosine combination given intravenously, as a slow bolus and at low doses to adenosine alone (given at its recommended dosage adjusted to patients' weight) for coronary flow reserve assessment (in 60-75 patients with stable ischemic heart disease) using transthoracic echodoppler

This study is a randomized open label study that implies the administration of asprin according to three different regimens. The aims of the study are: to establish whether coronary artery bypass surgery and / or aortic valve replacement surgery with bioprostheses is associated with changes in the rate of platelet regeneration that can reduce the effectiveness of aspirin administered at a dose of 100mg/die in terms of inhibition of platelet biosynthesis of thromboxane A2. to determine whether these patients need a different (shorter) interval of administration in order to completely and permanently inhibit the platelet COX-1. The endpoints of this study are: - To evaluate the changes in the levels of TXB2 and 12-HETE in serum at 12 and 24 hours after administration of aspirin and the changes in the levels of 11-dehydro TXB2 urinary 8-iso-PGF2 alpha urinary, 2-3 dinor-6-chetoPGF1 alpha, Verify-NOW Aspirin, platelets crosslinked at 12 and 24 hours after administration of aspirin

Bradykinin has been identified to contribute to the release of nitric oxide (NO), prostacyclin, and EDHF through activation of specific bradykinin 2 (B2) receptors, which is finally promoting a vasodilatory respone. Regular physical exercise training results in an improvement of endothelial function in patients with CAD. These positive effects were partially attributed to an increased expression of endothelial NO synthase (eNOS) and cyclooxygenase (COX) as a result of the training intervention. Aim of this trial is therefore to determine, whether the training-induced correction of endothelial dysfunction is also bradykinin-dependent.

To determine the effects of high or low intensity long-term exercise conditioning in patients with coronary artery disease.

1. Coronary artery bypass grafting (CABG) could be performed with or without extracorporeal circulation (ECC). 2. OSA (Obstructive Sleep Apnea) could be influenced by in intravenous perfusion. 3. ECC could influence the amount of intravenous perfusion administered to the patient. The aim of this study was to examine the influence of ECC on the development of OSA.

The purpose of this investigation is to compare subjects at high risk for silent myocardial ischemia in the placebo group to subjects at high risk for silent myocardial ischemia in the ranolazine group to determine if ranolazine can be used as a treatment to decrease silent myocardial ischemia (SMI). Subjects at high risk for silent myocardial ischemia are defined in this protocol as diabetics with stable ischemic heart disease. This study will look at the impact ranolazine treatment has on biomarkers that have been shown to be highly associated with increased risk of morbidity and mortality in relation to SMI. If the hypothesis is correct, further studies can be conducted to determine if treatment with ranolazine has impact on long-term outcomes such as hospitalizations, myocardial infarction, congestive heart failure or sudden cardiac death.

This study is designed to evaluate a new approach to the diagnosis of chronic or sub-acute chest pain patients in the out-patient setting. Patients in this study are selected to be "low-risk", meaning they are not having an acute or recent heart attack (AMI), based on screening blood tests and electrocardiograms (EKGs). In addition, these patients have a low or intermediate pre-test likelihood of the coronary artery disease (CAD), which means that probability of the CAD based on the available clinical and historical information, does not make a diagnosis of the CAD a certain clinical diagnosis in the particular patient and this, in turn, requires an additional diagnostic work up.

Background: - Heart disease is the leading cause of death and disabilities in the United States. Diets high in fruits and vegetables may reduce the risk of heart disease. Fruits, including red tart cherries and purple aroniaberries, may be especially beneficial. Researchers want to know how tart cherry and aroniaberry extracts affect heart health. Objective: - To study the benefits of tart cherry and aroniaberry extract on vascular function and other measures. These include inflammation, oxidation, and cholesterol. Eligibility: - Men and post-menopausal women ages 55 70 in good health and with normal or slightly high blood pressure or cholesterol. Design: Participants will be screened with a physical exam, medical history, and blood tests. Participants will have 6 visits. They will have blood taken at every visit. Visit 1: Blood vessel tests. Participants will lie down. Heart rhythm will be monitored. A device will be placed on the upper arm, and pictures of blood vessels will be taken. A blood pressure cuff will be tightened around the lower arm for 5 minutes. Cardio-Ankle-Vascular Index (CAVI). Blood pressure cuffs will be placed on both arms and legs. They will be tightened with air at the same time for a few minutes. Participants will be assigned to one of three groups. For 3 weeks each, in random order, they will take: aroniaberry capsules, tart cherry capsules, placebo capsules, and no capsules. Participants will answer questions online about their eating and exercise. Participants will be keep a record of what they eat for a few periods. They will come for a study visit every 3 weeks through week 15.