Loading clinical trials...
Loading clinical trials...
Showing 1-17 of 17 trials
NCT05756088
The goal of this research study is to understand if a blood test in people who have had heart transplants can detect and predict the following: * Blockages in the small blood vessels of the heart. * Whether small blockages can turn into more severe blockages in the future. Participants will undergo blood draws once every 3 months in the first year of the study (4 blood draws total, taking 15 minutes each) and their medical records will be reviewed for 3 years after the date they are enrolled in the study.
NCT07020039
In traditional coronary artery disease, patients often experience symptoms such as angina. However, heart transplant patients lack nerve connections in the transplanted heart and therefore usually do not notice any symptoms. For this reason, routine examinations are performed using traditional coronary angiography at one, three, and six years after transplantation, sometimes with the addition of coronary ultrasound. A new technique, photon-counting computed tomography, has now been developed and may potentially replace both traditional coronary angiography and intravascular ultrasound. In this study, we aim to investigate how well this method works in diagnosing coronary artery changes compared to the established methods.
NCT04770012
Cardiac allograft vasculopathy is a common complication affecting heart transplant patients. This condition causes narrowing of the heart arteries leading to graft dysfunction. The research team is investigating whether early antiplatelet therapy post heart transplant can prevent the development of CAV. This study will determine the feasibility of a large multicenter randomized placebo-controlled trial to answer this question.
NCT02798731
The aim of the study is to evaluate the impact of early microvascular disease assessed by coronary physiologic indices such as fractional flow reserve (FFR), coronary flow reserve (CFR), index of microvascular resistance (IMR) on future occurrence of cardiac allograft vasculopathy (CAV) in heart transplant recipients.
NCT05826444
The aim of the mCAV study is a comprehensive characterization of the genetic, morphological and functional phenotype of isolated microvascular graft vasculopathy (mCAV) after orthotopic heart transplantation (OHT). The utilized methods include dynamic echocardiography, magnetic resonance imaging, invasive microvascular resistance measurements, histology, cellular calcium-signaling and magnetocardiography as well as molecular genetic expression analysis (miRNA based).
NCT04193306
Cardiac allograft vasculopathy (CAV) represents the leading cause of late morbidity and mortality in heart transplant recipients as the second most frequent cause of all deaths at 3 years. In distinction from general coronary atherosclerosis, CAV affects diffusely the entire coronary vasculature with marked intimal proliferation and concentric vascular thickening and fibrosis. It was demonstrated that most of the intimal thickening due to CAV occurs during the first year after transplantation. Furthermore, the severity of the CAV appears to correlate with lipid abnormalities and elevated low-density lipoprotein cholesterol (LDL-C) is very common after transplantation with nadir of LDL levels occurring at 6 months. Because of drug-drug interactions, heart transplant recipients cannot be treated with adequate doses of statins to achieve desirable reduction of LDL-C levels (reduction ˂ 60% of LDL-C). The use of alternative lipid-lowering drugs including bile acid sequestrates, fibrates, nicotinic acid or ezetimibe is not recommended in post-transplant scenario. Inhibition of proprotein convertase subtilisin/kexin type 9 (PCSK9) increase availability has emerged as a novel drug tool for LDL-C lowering, capable to lower LDL-C by more than 60% even in statin-treated patients with very good safety profile. Although heart transplant recipients fulfill approved indication and standard clinical guidelines of a PCSK9 inhibitor, alirocumab, there are no available data on use of PCSK9 inhibitor in post-transplant situation. The purpose of the ACAV study is to clarify efficacy and safety of alirocumab compared to placebo administered during the first year after transplantation in heart transplant recipients in addition to background atorvastatin therapy. Except lipid profile, optical coherence tomography (OCT) will be performed as the objective efficacy endpoint to examine thickness and lumen of coronary vessels. It is expected that inhibition of PCSK9 in heart transplant recipient will dramatically improve post-transplant lipoprotein levels and perhaps slow down development of CAV in the most critical period of the first year after transplantation.
NCT04791852
Cross-sectional study. We will prospectively obtain ddcf-DNA levels in all patients who undergo routine coronary angiography \> 1 year after HT. Our main goal is to evaluate the performance of Donor-derived Cell Free DNA (ddcf-DNA) as a biomarker of CAV.
NCT02013037
All individuals who receive a heart transplant are at risk for developing antibody-mediated rejection (AMR). An antibody is a protein produced by the body's immune system when it detects a foreign substance, called an antigen. The mechanism of an antibody is to attack an antigen. In antibody mediated rejection, antibodies will attack the transplanted heart, causing injury to the heart. The purpose of this investigation is to determine if a study drug, called eculizumab (Soliris), is safe to use in heart transplant recipients, and determine if it reduces risk of antibody-mediated rejection.
NCT02082821
Heart transplantation (HT) is a lifesaving procedure for patients with end-stage heart failure and provides a better survival and quality of life if compared to medical treatment. HT is subject to alloimmune response, which, if left uncontrolled, is capable of jeopardizing long-term cardiac function. Advances in immunosuppression have enhanced the survival of HT patients. Nearly 2500 HT per year have been performed in the US during the last 10 years and despite significant improvements, long-term survival rates remain poor. More than 20% of patients do not survive more than 3 years, and those who survive are afflicted by long-term complications of alloimmunity and chronic immunosuppression. Life expectancy of patients who lose cardiac allografts is dramatically poor due to the absence of any therapeutic tool apart from re-transplantation, which is plagued by poor outcomes. The identification of novel therapeutic targets is thus mandatory. ATP/P2X7R signaling in T cells is highly relevant for cardiac allograft survival. ATP is a small molecule present at high concentrations inside cells; it is released as extracellular ATP (eATP) following cell damage or death where it acts as a danger signal. ATP is sensed by the P2X receptors (seven receptors named P2X1-7), mainly expressed by T lymphocytes. We have recently demonstrated that the ATP/P2X7R axis has a key role in cardiac allograft survival in humans and mice. Cardiac allograft vasculopathy (CAV) is a major limiting factor for HT survival; indeed CAV occurs in 50% of HT recipients by 5 years after transplantation and invariably results in allograft failure. CAV is clearly of immunological origin, as syngeneic murine grafts do not develop it. Once CAV occurs, the most definitive treatment is re-transplantation, but survival remains poor. We hypothesize that a single nucleotide polymorphysm (SNP) loss-of-function P2X7R mutation (p.Glu496Ala / c.1513A\>C, rs3751143) generates a compensatory upregulation of the other purinergic receptors (P2XsR), thus creating a state of hypersensitivity to eATP. This eATP hypersensitivity results in an abnormal generation of Th1/Th17 cells, that leads to CAV and early cardiac allograft loss. Our study will answer a fundamental question: What is the effect of the P2X7R loss-of-function mutation on the immune system? Our goal is to generate the first targeted-therapy for a selected group of cardiac transplant recipients.
NCT01812434
Hypothesis 1: Treatment of heart transplant recipients with sildenafil, a PDE-5 inhibitor, will improve small artery elasticity (SAE) when compared to placebo. Hypothesis 2: PDE-5 inhibition will improve endothelial function, resulting in increased production of nitric oxide, reduced activation of circulating endothelial cells, and increased endothelial progenitor cells.
NCT02880137
Is real-time myocardial perfusion echocardiography (RTMPE) a feasible and effective non-invasive method to detect significant Coronary Allograft Vasculopathy in pediatric and adult cardiac transplant recipients? Will perfusion deficits correlate with significant coronary artery stenosis identified by standard stress echocardiography and Invasive Coronary Angiography (ICA), and identify diffuse small vessel disease more effectively than current non-invasive techniques?
NCT03808324
This study will investigate the prevalence of allograft vasculopathy and unexplained graft dysfunction during long-term follow-up after heart transplantation. Risk factors as well diagnostic approaches will be investigated.
NCT01848301
Coronary allograft vasculopathy (CAV) is the leading cause of late graft failure and second leading cause of late mortality after heart transplantation. CAV has been associated with a variety of traditional risk factors for atherosclerosis; however, immune mediated injury from development of de-novo donor-specific antibodies after transplantation also likely plays an important role. Similar to the progression of traditional atherosclerosis, it is likely that endothelial dysfunction is the precursor to the development of intimal thickening and CAV. The investigators hypothesize that coronary allograft vasculopathy after heart transplantation as defined by progressive neointimal hyperplasia is preceded by endothelial dysfunction, which in turn is at least partly mediated by donor specific antibodies. The investigators are proposing a prospective study in humans to test the above hypothesis and further mechanistically understand how CAV progresses. In this study the investigators will test for coronary endothelial function by infusing acetylcholine into the coronary artery and measure intimal hyperplasia by optical coherence tomography (OCT) and compare findings in patients with and without donor specific antibodies.
NCT01403142
Cardiac allograft vasculopathy (CAV) is a unique form of accelerated plaque formation seen in the coronary arteries of patients who have received heart transplantation. It is a major cause of morbidity and mortality in patients after heart transplant. Little progress has been made in characterizing this disease process, with more sophisticated imaging allowing for more detailed analysis of CAV, superior stratification of transplant recipients is possible and earlier interventions can be performed if necessary to prevent mortality and graft loss. Optical Coherence Tomography (OCT) is a novel imaging modality with much higher resolution then Intra-Vascular Ultrasound (IVUS). This study will involve examining patients post-heart transplant using this high-resolution imaging modality. It is currently the standard care for patients post-heart transplant to receive annual coronary angiograms with close follow up. Patients will be imaged using OCT at the time of their routine annual angiogram, and will be re-imaged one year later at the time of the next annual angiogram or earlier if clinically indicated. The study goal is to better characterize CAV in vivo with OCT imaging and to try to identify patterns of the disease, including intra-coronary risk assessment.
NCT01305382
Abnormal peripheral endothelial function and alterations in circulating biomarkers that are associated with endothelial activation and inflammation correlate with angiographic evidence of cardiac allograft vasculopathy, defined as greater than 25% stenosis in a major coronary artery.
NCT01186250
The purpose of this study is to determine the benefit of using the FDA-approved insulin-sensitizing agent, Pioglitazone, on human heart transplant recipients. The objectives of this project are to (1) determine if pioglitazone effectively treats insulin resistance in heart transplant recipients, and (2) to determine whether pioglitazone therapy after heart transplantation impacts the development or progression of cardiac allograft vasculopathy (CAV), a form of chronic rejection after heart transplantation.
NCT01569334
Heart transplantation is the best option for patients with end-stage heart failure. Cardiac allograft vasculopathy (CAV) is the leading cause of death following cardiac transplantation and is not managed by current therapies. Its pathogenesis traduces in an accelerated form of coronary artery disease (CAD) with similarities to atherosclerosis but also particular features of endothelial dysfunction associated to the alloimmune conflict and humoral responses toward the graft. Intravascular ultrasound (IVUS) is the validated invasive method for late CAV diagnosis, but occurs lesions are established. Identification of reliable non-invasive early endothelial injury biomarkers that reflect mechanisms of cardiac damage thus remain a major challenge to optimize therapeutic management of post transplant morbidity. Endothelial dysfunction is a central feature of both CAV and CAD and results from a desquilibrium in the balance of endothelial lesion and repair that is partly controlled by recipient immune system. Through their expression of receptors sensing antibodies (FcR CD16) and endothelial stress-induced signals (CX3CR1 fractalkine receptor and NKG2D MICA receptors), Natural Killer (NK) cells represent effector cells with unique potential to generate both humoral and innate immune injury of graft endothelium.