View clinical trials related to Ventricular Dysfunction.
Filter by:The purpose of this study is to determine whether giving cardiosphere-derived stem cells (CDCs) to patients with decreased heart function and/or a large amount of damaged muscle after a heart attack is safe. CDCs are cells grown from small biopsy samples taken from the heart. Giving a patient their own CDCs is an investigational procedure that has been approved by the Food and Drug Administration for this study. In addition to determining whether this treatment is safe, the study will also examine whether it can decrease the amount of heart muscle damage and/or improve heart function after a heart attack. The amount of heart muscle damage and the function of the heart directly affects prognosis (the predicted course of the disease), and the development of heart failure and other complications some patients experience after a heart attack. By way of background, scientists and physicians believed, until just a few years ago, that heart muscle damaged after a heart attack could not be replaced. Recently, however, scientists discovered that new heart muscle can form, or be regenerated, and that this process can be enhanced (or increased) by the administration of large numbers of certain cells isolated from the heart or bone marrow. These cells can be stem cells, or cells derived from stem cells, and they may achieve their benefit by forming new heart muscle cells, becoming heart muscle cells themselves, or releasing substances which increase the ability of already existing stem cells to form new heart muscle. All of the studies conducted so far have been experimental and no cell type is approved for routine clinical care of patients with heart disease. However, studies involving bone marrow stem cells do indicate some small improvement in heart function and one large study demonstrated a decrease in clinical events in the group which received bone marrow cells. Investigators of this study decided to study CDCs because they come from a person's own body, and therefore have no foreign immune antigens which may be rejected. Since the cells come from the person's heart, they are more likely to form heart tissue. In addition, animal studies indicate no safety problems and that these cells are capable of forming heart muscle and blood vessel cells after heart attacks. The investigators are now studying whether the same is true in humans.
Coronary artery disease (CAD) is a common disorder that can lead to heart failure. Not all people with CAD are eligible for today's standard treatments. One new treatment approach uses stem cells—specialized cells capable of developing into other types of cells—to stimulate growth of new blood vessels for the heart. This study will determine the safety and effectiveness of withdrawing stem cells from someone's bone marrow and injecting those cells into the person's heart as a way of treating people with CAD and heart failure.
Sildenafil (Viagra) is known to reduce pulmonary hypertension. Heart failure patients also have pulmonary hypertension and several recent reports have shown that sildenafil leads to an improvement in their exercise capacity. In these studies sildenafil caused a reduction in the pulmonary and systemic vascular resistances, improved pulmonary gas diffusion and perhaps increased cardiac output. It is uncertain if left ventricular filling pressures are reduced and whether there is improvement in left ventricular relaxation. The investigators hypothesize that in heart failure patients the improvement in exercise capacity associated with sildenafil is related to a significant reduction in left ventricular filling pressures. The investigators propose to study 20 patients with stable but moderately symptomatic heart failure. The study design is a randomized cross-over trial of the administration of a single dose of sildenafil 50 mg or a matching placebo. Exercise capacity will be determined before and after the oral administration of sildenafil 50 mg or placebo. Left ventricular filling pressures will be assessed by Doppler echocardiography and the serum level of B-type natriuretic peptide (BNP is known to increase with higher left ventricular filling pressures). After an initial echocardiogram and performing a 6 minute walk test, the patient will then be given either sildenafil or a matching placebo in a randomized double-blind fashion. One hr later a blood sample for serum BNP, the echocardiogram and the 6 minute walk test will be repeated.
The technique of transplanting progenitor cells into a region of damaged myocardium, termed cellular cardiomyoplasty, is a potentially new therapeutic modality designed to replace or repair necrotic, scarred, or dysfunctional myocardium. Ideally, graft cells should be readily available, easy to culture to ensure adequate quantities for transplantation, and able to survive in host myocardium; often a hostile environment of limited blood supply and immunorejection. Whether effective cellular regenerative strategies require that administered cells differentiate into adult cardiomyocytes and couple electromechanically with the surrounding myocardium is increasingly controversial, and recent evidence suggests that this may not be required for effective cardiac repair. Most importantly, transplantation of graft cells should improve cardiac function and prevent adverse ventricular remodeling. To date, a number of candidate cells have been transplanted in experimental models, including fetal and neonatal cardiomyocytes, embryonic stem cell-derived myocytes, tissue engineered contractile grafts, skeletal myoblasts, several cell types derived from adult bone marrow, and cardiac precursors residing within the heart itself. There has been substantial clinical development in the use of whole bone marrow and skeletal myoblast preparations in studies enrolling both post-infarction patients, and patients with chronic ischemic left ventricular dysfunction and heart failure. The effects of bone-marrow derived mesenchymal stem cells (MSCs) have also been studies clinically. Currently, bone marrow or bone marrow-derived cells represent highly promising modality for cardiac repair. The totality of evidence from trials investigating autologous whole bone marrow infusions into patients following myocardial infarction supports the safety of this approach. In terms of efficacy, increases in ejection fraction are reported in the majority of the trials. Chronic ischemic left ventricular dysfunction resulting from heart disease is a common and problematic condition; definitive therapy in the form of heart transplantation is available to only a tiny minority of eligible patients. Cellular cardiomyoplasty for chronic heart failure has been studied less than for acute MI, but represents a potentially important alternative for this disease.
To explore if AZD1305 compromises left ventricular performance in patients with left ventricular dysfunction
More than 1 million Americans suffer heart attacks each year. Although current treatments are able to stabilize the condition of the heart, none is able to restore heart function as it was prior to the heart attack. Adult stem cells, which are immature cells that can become many different types of cells, may offer a potential means of reversing or preventing permanent damage caused by a heart attack. Recent studies have shown promise in using adult stem cells from bone marrow to reverse damage to the heart muscle caused by a heart attack, but more research is needed to assess the safety and effectiveness of stem cell use and to discover the best time to administer treatment. This study will evaluate the safety and effectiveness of using adult stem cell infusions 2 to 3 weeks after a heart attack for improving heart function in people who have had a recent heart attack and a common procedure called a percutaneous coronary intervention (PCI).
Heart attacks are a leading cause of death for both men and women in the United States. A heart attack occurs when blood flow to the heart is restricted, commonly due to a blood clot that has formed in one of the coronary arteries. If the clot becomes large enough, blood flow to the heart can be blocked almost completely and the heart muscle in that area can suffer permanent injury or death. Although a percutaneous coronary intervention (PCI) can be used to open up the blocked artery and restore blood flow to the heart muscle, there may be a significant amount of heart tissue that has been irreversibly damaged. Recent studies have shown that adult stem cells from bone marrow may be able to improve heart function after a heart attack. This study will evaluate the safety and effectiveness of using adult stem cells for improving heart function in people who have had a recent heart attack and a PCI.
Background: Residual pulmonary regurgitation following repair of tetralogy of Fallot, in particular the use of a transannular patch, has been shown to correlate with the development of right ventricular dysfunction. Optimal timing of pulmonary valve replacement, therefore, is important to preserve right ventricular function. Several recent studies suggested that a threshold of right ventricular end-diastolic volume for intervention, in order to preserve the likelihood of adequate reverse remodeling, is in the region of 150 to 200 ml/m2 body surface area. However, there is evidence that right ventricular function does not always recover following pulmonary valve replacement even if the end-diastolic volume is below this cut-off. In addition, previous studies suggested that early dysfunction may be present before symptoms occur. However, early dysfunction is difficult to assess. Methods: Analysis of right ventricular function by pressure-volume loops has been extensively evaluated in experimental studies and is generally considered the optimal way to quantify right ventricular function. By recording a family of pressure-volume loops during reduction of preload, achieved by temporary balloon occlusion of the inferior caval vein, the contractility can be calculated by the slope of the endsystolic pressure-volume relation (elastance). Changes of contractility following dobutamine infusion could be noted by changes of elastance. The increase of the slope during dobutamine demonstrates the contractility reserve of the right ventricle. Purpose: To evaluate the right ventricular contractility reserve to determine early ventricular dysfunction after repair of tetralogy of Fallot.
To compare a surgical approach of LV lead placement for BIV pacing with the conventional transvenous approach by assessment of differences on the effects on cardiac perfusion and relate this to the clinical cardiac function.
The purpose of the Consulta clinical study is to evaluate the overall system safety and clinical performance of the Consulta Implantable Cardioverter Defibrillator with Cardiac Resynchronization Therapy (CRT-D).