View clinical trials related to Vascular Diseases.
Filter by:The purpose of this study is to investigate the current standard of wound care following vascular operations compared to to a negative pressure wound therapy (vacuum dressing) and the rate of surgical site infections (SSIs) in patients undergoing surgery to restore blood flow to the lower limb(s). Negative pressure wound therapy consists of a closed, sealed system that produces negative pressure (vacuum) to the wound surface. The device itself consists of open-cell foam that is sealed with an occlusive adhesive dressing (covers and sticks to the incision) and suction is maintained by connecting suction tubes to a vacuum pump and waste collector. The investigators objectives are to determine whether there will be any reduction in surgical site infection and this potential reduction will influence length of hospital stay, emergency room visits, antibiotic use and need for re-operation.
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.
Objective: - To assess the relationship between coronary allograft vasculopathy (CAV) and graft function, and to evaluate non-invasive methods for CAV diagnosis. - To assess left ventricular (LV) and right ventricular (RV) function in the acute phase and serially during the first year after transplantation. - To evaluate the impact of acute and repetitive rejection on the longitudinal myocardial function Hypothesis 1. Timing of development and degree of CAV can be measured non-invasively combining myocardial longitudinal deformation (by advanced echocardiography) and coronary flow velocity reserve (CFVR) (by echocardiography and PET). This combination of methods can detect CAV before it is angiographically visual and gives supplementary information of the impact on myocardial graft function. 2. Longitudinal deformation, 3D echocardiography, cardiac magnetic resonance imaging (CMRI) and PET can be used for RV and LV myocardial function assessment and represent more valid markers of the function than standard echocardiography in heart transplant (HTX) patients. 3. Myocardial longitudinal deformation is a better marker of acute rejections than conventional ejection fraction (EF). Background The most frequent heart related death causes after HTX are CAV, acute graft failure and rejection. CAV is characterized by diffuse concentric intima thickening involving both epicardial vessels and the coronary microvascular system. In our clinical approach HTX-patients are followed with annual CAG and standard echocardiography with estimation of LV systolic function by EF. Standard echocardiography has not proven benefit in the diagnosis of CAV. CAG often misses CAV in early phases. In various cardiac diseases it is well known that ischemia and fibrosis often affect the endocardial longitudinal oriented layers. Longitudinal deformation by advanced echocardiography has shown to be better markers for systolic function in HTX patients compared to standard EF. Longitudinal LV systolic function is dependent of endocardial perfusion. CFVR represents the capacity of the coronary circulation to dilate due to metabolic demands and has been shown to correlate with longitudinal deformation in myocardial infarction. CFVR measurements in HTX patients with advanced echocardiography and PET scan have shown a significant correlation to CAV. RV failure is an early, potentially fatal, complication to HTX. The function and change over time of RV have not been fully studied using modern echocardiographic techniques or assessment by CMRI. Acute rejection is an inflammatory response often diagnosed by routine biopsies (gold standard). These are expensive, time consuming and inconvenient for the patient. The role of conventional echocardiography has not yet found a significant role in the diagnostics of acute rejections and furthermore how repeated rejections influence on graft function is not well described. Study 1 A cross sectional study consisting of 50 stabile HTX patients. These will be selected with 25 patients with no or light CAV and 25 patients with moderate or severe CAV. Severity of CAV will be evaluated by: - CAG - CFVR measurement by advanced echocardiography and PET. Graft function will be evaluated by: - Advanced echocardiography at rest end during bicycle exercise. - CMRI including assessment of LV and RV EF, strain and mass. - During rest and bicycle exercise echocardiography simultaneously right heart catheterization are performed for hemodynamic measurement Study 2 A prospective cohort study with 20-25 newly transplanted patients over a period of 12 months. LV and RV function will be measured by: - Advanced echocardiography - CFVR measurement (echocardiography and PET) - CMRI for LV and RV EF, strain and mass - Right heart catheterization Study 3 Prospective examination of correlation between graft function, CAV and rejection. Information of former episodes of acute rejection is collected retrospective. Study objectives are all living HTX patients (approx. 200) in the period of 2011-2013. Advanced echocardiography (including longitudinal deformation), biopsies (rejection evaluation) and CAG (CAV evaluation).
The purpose of this study is to evaluate the efficacy and safety of aflibercept for treatment of polypoidal choroidal vasculopathy without active polyp.
The purpose of the study is to compare non-contrast abdominal MR Angiogram (MRA) syngo NATIVE sequence performed on a 3T Verio Siemens magnet to a standard contrast-enhanced MRA performed as part of routine clinical care in patients with normal renal function to determine if the non-contrast NATIVE sequence is a viable alternative to contrast enhanced MRA in patients with renal insufficiency. There are no interventions--this is an observational study.
The purpose of this Randomized Study to evaluate the safety and efficacy of the Excel-II DES compared to the EXCEL DES in the treatment of patients with de novo coronary artery lesions.
This study aims to demonstrate if remote ischaemic preconditioning (RIPC) may confer renal protection in patients undergoing peripheral angioplasty. Patients will be randomised to receive RIPC and biomarkers for renal injury will be analysed post procedure to determine if any protective benefit was obtained.
This study is intended to collect safety and effectiveness data on the Cook Micronized Small Intestinal Submucosa (SIS)
The diagnosis of a patient with pulmonary hypertension (PH) requires many investigations. At present cardiac catheterisation is the cornerstone investigation in these patients where it is used to establish disease severity and estimate prognosis. It is an invasive procedure which is expensive and not without risk to the patient. Despite the multitude of tests performed, identifying those patients with PH who have a poor diagnosis can be difficult. The aim of this study is to improve the assessment of patients with PH using novel magnetic resonance techniques.
Description of the phenomena "Slow Coronary Flow" (SCF), according to the data that has been collected from patients hospitalized with specific criteria. Clinical follow-up of these patients to determine whether they suffered from any cardial or psychological disorders that might be a result of SCF.