View clinical trials related to Myocardial Ischemia.
Filter by:Patients with narrowed heart arteries who undergo coronary angiography (imaging of the heart's blood vessels) may participate in this "heart mapping" study designed to gain information about the condition of different areas of the heart muscle. In coronary angiography, a thin tube called a catheter is inserted through a small incision in the groin and pushed up to the heart. There, a contrast dye is injected, revealing areas of blockage in the coronary arteries-the vessels that supply blood to the heart muscle. As soon as the angiography is completed, patients in this study will undergo another procedure called "Biosense mapping." For this procedure, a special catheter with a tiny sensor at the tip will be inserted into the sheath that was used for the angiography and advanced to the heart's main pumping chamber-the left ventricle. The sensor detects the pattern of an electromagnetic field generated from a pad under the patient, and an image of the precise location of the catheter in 3-dimensional space can be seen on a computer screen. The catheter is then navigated to various precise locations in the ventricle, producing an electromechanical map that distinguishes scarred muscle tissue from healthy tissue-information that can be important in guiding treatment. When this mapping is completed, the patient will be given a drug called dobutamine to increase the heartbeat, and the mapping will be repeated. The heart may also be mapped while the heart rate is increased with a pacing catheter to simulate exercise. The test will be stopped if adverse side effects develop. Patients in the study will also have magnetic resonance imaging (MRI) and PET (positron emission tomography) scans to get additional information about the heart muscle, such as blood flow and metabolism rate.
This study is designed to compare two different echocardiographic techniques in the evaluation of heart disease (coronary artery disease). Both tests called Myocardial Contrast Echocardiography with Pharmacologic Stress and Stress Echocardiography with Dobutamine, are performed using a standard echocardiographic machine. Myocardial Contrast Echocardiography (MCE) does not use radioactivity. It uses sound waves like standard echocardiography. However, with MCE patients receive an injection of a "contrast agent" directly into the blood stream through a vein. The contrast agent, called Optison, is made of tiny microbubbles smaller than red blood cells. The echocardiogram can detect these microbubbles in the small blood vessels of the heart muscle and allow researchers to find areas of the heart receiving less blood flow than others. It is important to observe the heart during exercise because there are changes in blood flow. Since MCE cannot be performed when the patient is exercising, researchers give medication (adenosine) that stimulates the heart and creates a situation similar to exercise. Stress Echocardiography with Dobutamine does not use radioactivity. It uses sound waves like standard echocardiography. During this echocardiogram patients receive doses of a medication called dobutamine that stimulates the heart to beat stronger and faster. The purpose of this study is to evaluate the accuracy of MCE compared to stress echocardiography at detecting coronary artery disease (CAD).
Blood flows to areas of the heart providing oxygen and fuel to the pumping muscle. Occasionally the arteries providing the fuel can become blocked. This occurs in coronary artery disease. Magnetic resonance imaging (MRI) can be used to evaluate the blood flow to different areas of the heart muscle. In this study magnetic resonance imaging will be compared to other diagnostic tests (radionucleotide perfusion studies) capable of measuring blood flow to heart muscle.
The human heart is divided into four chambers. One of the four chambers, the left ventricle, is the chamber mainly responsible for pumping blood out of the heart into circulation. Hypertrophic cardiomyopathy (HCM) is a genetically inherited disease causing an abnormal thickening of the heart muscle, especially the muscle making up the left ventricle. When the left ventricle becomes abnormally large it is called left ventricular hypertrophy (LVH). This condition can cause symptoms of chest pain, shortness of breath, fatigue, and heart beat palpitations. This study is designed to compare the ability of two drugs (enalapril and losartan) to improve symptoms and heart function of patients diagnosed with hypertrophic cardiomyopathy (HCM). Researchers have decided to compare these drugs because each one has been used to treat patients with other diseases causing thickening of the heart muscle. In these other conditions, enalapril and losartan have improved symptoms, decreased the thickness of heart muscle, improved blood flow and supply to the heart muscle, and improved the pumping action of the heart muscle. In this study researchers will compare the effectiveness of enalapril and losartan when given separately and together to patients with hypertrophic cardiomyopathy (HCM).
Myocardial ischemia is a heart condition in which not enough blood supply and oxygen reaches the heart muscle. Damage to the major blood vessels of the heart (coronary artery disease), minor blood vessels of the heart (microvascular heart disease), or damage to the heart muscle (hypertrophic cardiomyopathy) can cause myocardial ischemia. Any of theses three conditions can cause patients to experience chest pain and other symptoms as well as cause the heart to function improperly. In order to detect myocardial ischemia researchers can use tests to measure the movement of the walls of the heart. Walls receiving inadequate supplies of blood often move less and occasionally move in the opposite direction. Some of the tests may require patients to receive injections of radioactive tracers. The radioactive material acts to enhance 3 dimensional pictures of the heart and helps to identify areas of ischemia. The purpose of this study is to determine whether 3-dimensional imaging (tomography) with radioactive tracers can provide more important information about heart wall function than routine diagnostic tests.
To determine the acceptability and benefits of use of a dietary supplement of the phytoestrogen, genistein, versus placebo on heart disease risk factors, bone density, and psychosocial outcomes in postmenopausal women.
To address cardiovascular disease, cancer, and osteoporosis, the most common causes of death, disability, and impaired quality of life in postmenopausal women. The three major components of the WHI are: a randomized controlled clinical trial of hormone replacement therapy (HRT), dietary modification (DM), and calcium/vitamin D supplementation (CaD); an observational study (OS); and a community prevention study (CPS). On October 1, 1997, administration of the WHI was transferred to the NHLBI where it is conducted as a consortium effort led by the NHLBI in cooperation with the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), the National Cancer Institute (NCI), and the National Institute on Aging (NIA).
To determine whether early intravenous magnesium treatment of patients with suspected acute myocardial infarction reduces mortality.
To determine if postmenopausal hormone replacement therapy in women following coronary bypass surgery would reduce the occurrence of graft occlusion and delay the development of graft atherosclerosis.
To compare three accepted modes of myocardial preservation, warm, tepid, and cold blood cardioplegia, coinciding with normothermic (37 degrees centigrade), tepid (32 degrees centigrade) and hypothermic (8 to 10 degrees centigrade) cardiopulmonary bypass (CPB) to define differences in neurologic function in coronary artery bypass graft (CABG) patients.