View clinical trials related to Cardiomyopathies.
Filter by: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).
DDD pacing improves symptoms and relieves LV outflow tract (LVOT) obstruction in most patients with hypertrophic cardiomyopathy (HCM). Notably, when pacing is temporarily discontinued, the beneficial effects of pacing are evident in sinus rhythm. The long term results of this novel therapy are, however, uncertain. We propose (1) to record the hemodynamic changes following >4 years of pacing; and (2) to determine whether DDD pacing continues to be necessary in patients who have had a substantial relief of their LVOT obstruction. Patients who have had >50% reduction in LVOT pressure gradients will be randomized to two pacing modalities: DDD at 70 beats per minute and AAI pacing at 70 beats per minute (DDD switched off), and reevaluated after a six-month period.
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.
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 the circulation. Diseases of the heart like congestive heart failure (CHF), can cause the left ventricle to function improperly. Medications called beta-blockers appear to reverse the abnormalities in the left ventricle and frequently improve the function of the left ventricle in patients with different kinds of heart disease. How beta-blockers improve left ventricle function is unknown. One possible reason for improved function of the left ventricle with beta-blockers is improved blood flow to the heart muscle. When a region of the heart is active, it uses more fuel in the form of oxygen and sugar (glucose). As heart activity increases, blood flow to and from the area of activity increases also. Knowing these facts, researchers can use radioactive sugar (glucose) and positron emission tomography (PET) scans to observe what areas of the heart are receiving more blood flow. In this study researchers plan to measure glucose use in heart muscle and blood flow to the heart muscle in patients with CHF taking beta-blockers.
Several studies have shown that specialized pacemaking devices (DDD pacing) can improve the symptoms associated with hypertrophic cardiomyopathy (HCM) in adults. In addition, studies have also shown that specialized pacemaking devices (DDD pacing) can improve conditions of HCM in children. However, growth of the body and organs, including the heart, is very rapid during childhood. Therefore the long-term effects of DDD pacing in children are unknown. The purpose of this study is to examine the growth rate and nutrition of children with HCM. Due to this heart condition and the restrictions that are often placed on the child's activity level, children with HCM may grow at a slower rat and may have a greater tendency to be overweight. Children participating in the study will have their growth rate and nutritional status measured before the study begins and throughout the course of the study. Findings in this research study will not directly benefit the patients participating in it. However, information gathered as a result of this study may lead to improvements in the management of children with HCM in the future.
In this study researchers will admit and evaluate patients with known or suspected heart disease referred to the Cardiology Branch of the National Heart, Lung, and Blood Institute (NHLBI). Patients participating in this study will undergo a general medical evaluation, including blood tests, urine, examination, chest x-ray and electrocardiogram (EKG). In addition, patients may be asked to have an echocardiogram (ultrasound scan of the heart) and to perform an exercise stress test. These tests are designed to assess the types and causes of patient's heart diseases and to determine if they can participate in other, specific research studies.
Hypertrophic cardiomyopathy (HCM) is a genetically inherited heart disease. It causes thickening of heart muscle, especially the chamber responsible for pumping blood out of the heart, the left ventricle. Hypertrophic cardiomyopathy (HCM) is the most important cause of sudden death in apparently healthy young people. A genetic test called linkage analysis is used to locate genes causing inherited diseases like HCM. Linkage analysis requires large families to be evaluated clinically in order to identify the members with and without the disease. In this study researchers will collect samples of DNA from family members of patients with HCM. The diagnosis of the disease will be made by history and physical examination, electrocardiogram (12 lead ECG), and ultrasound of the heart (2-D echocardiogram). The ability of the researchers to locate the gene responsible for the disease improves with increases in the size of the family and members evaluated. In order to continue research on the genetic causes of heart disease, researchers intend on studying families with specific genetic mutations (beta-MHC) causing HCM. Researcher plan to also study families with HCM not linked to specific gene mutations (beta-MHC).
To determine if the chronic administration of enalapril, an inhibitor of angiotensin converting enzyme (ACE), reduces progression of cardiac dysfunction in pediatric oncology patients who have received anthracyclines, and who are not currently on digoxin, diuretics, or vasodilators for heart failure.