Left Atrial Appendage Occlusion With WATCHMAN® Device in Patients With Non-valvular Atrial Fibrillation...
Atrial FibrillationHeart Diseases5 moreAtrial fibrillation (AF) is more common in patients with renal disease compared to the general population an risk increase to as much as 10 times in patients on hemodialysis (HD). Stroke is an important cause of morbidity, mortality and suffering for patients with end-stage chronic kidney disease (ESCKD) on hemodialysis.The risk of bleeding in these patients can be roughly 5-fold higher that without it. Current guidelines recommend the use of oral anticoagulants (AO) to prevent stroke or systemic thromboembolism in high-risk patients with AF. Left atrial appendage occlusion (LAAO) reduces the risk of bleeding while allows thromboembolic stroke prevention. The aim of the study is to assess the procedural safety on stroke and bleeding prevention of LAAC in patients with non-valvular atrial fibrillation (NVAF) and ESCKD on HD.
Ferumoxytol Enhanced Magnetic Resonance Angiography in Chronic Kidney Disease
Ferric CompoundsMagnetic Resonance Angiography3 moreConventional vascular imaging techniques are often either contra-indicated in chronic kidney disease (CKD) patients due to their relative invasiveness, risks and cost. Computed tomography angiography (CTA) requires radiation and nephrotoxic iodinated contrast which may precipitate significant worsening of renal function and even prompt the need for institution of dialysis. Magnetic resonance angiography (MRA) using gadolinium-based contrast agents has been associated with the rare disease nephrogenic systemic fibrosis. Alternative imaging methods also have drawbacks: for example, this frail patient group has a higher risk of complications from conventional invasive catheter-based angiography, non-contrast-enhanced MRA allows visualization of smaller arteries but is less accurate for larger vascular structures, and ultrasound is often not appropriate for evaluation of the deep vessels of the abdomen and pelvis. Ferumoxytol is an ultrasmall superparamagnetic iron oxide particle encapsulated by a semisynthetic carbohydrate, which was initially developed as a magnetic resonance imaging (MRI) contrast agent in 2000. However, interest in ferumoxytol as a therapeutic agent for the treatment of iron deficiency anaemia in the setting of CKD eclipsed its use as MRI contrast agent. During the last decade, ferumoxytol has gained appeal as an MRI contrast agent in patients with estimated glomerular filtration rates <30mL/min and there are reports in the literature for its safe use and utility in both adult and pediatric patients with CKD. Participants will be selected from those who have been referred for assessment prior to kidney transplant or prior to vascular access creation for haemodialysis and will be divided into three groups. The first group will include patients who will undergo a CTA of abdominal and aortoiliac vasculature as part of their preparation for potential kidney transplantation. The second and third groups will include patients who are having a fistula or a graft created for dialysis, respectively. These patients are routinely having US vascular mapping to visualise the blood vessels before a fistula or a graft is created. Additionally, patients included in the second and third groups are routinely having surveillance scans of their fistula or graft at 6 weeks following creation. Study participants undergoing standard imaging tests as part of their clinical care will also have ferumoxytol-enhanced MRA (FeMRA).
Biomarker Effectiveness Analysis in Contrast Nephropathy (BEACON)
Acute Renal FailureKidney Diseases2 moreThis study is an observational non-interventional study which will examine a) the accuracy of biomarkers in predicting renal and cardiovascular outcomes after contrast-induced acute kidney injury. This study will obtain de-identified human plasma & urine samples and corresponding de-identified research study data on subjects who are enrolled into the Prevention of Serious Adverse Events Following Angiography (PRESERVE) study and Biomarker Collection and Analysis in the PRESERVE Trial (VA CSP #578). Biomarker analyses will be performed on the de-identified samples and merged with de-identified research study data.
Evaluating the Effect of Standard-of-care Erythropoiesis-stimulating Agents on Forearm Blood Flow...
Cardiovascular DiseasesChronic Kidney DiseaseIn people diagnosed with chronic kidney disease (CKD) anaemia is a common problem and is often treated with EPO (Erythropoietin). One form of EPO used is Darbepoetin (Aranesp®). EPO is safe to use but it has been associated with a rise in blood pressure (BP) in some individuals. The reasons for this are not clear. To try to explain this, this study will look at how EPO affects certain substances in the blood that influence how blood vessels contract and relax. This will be conducted by infusing small amounts of Acetylcholine, BQ123 and Noradrenaline into the arm vessels of volunteers using an established method called Forearm blood flow (plethysmography). Volunteers recruited for this study will include CKD patients undergoing therapy with Darbepoetin as part of their normal NHS care as well as healthy people not on treatment, who will act as controls. This is an observational pilot study of changes in physiology before and after Darbepoetin. It will provide valuable data for a later study comparing Darbepoetin to novel agents which work via different pathways to treat anaemia.
World Trade Center Kidney-Link
Chronic Kidney DiseasesObstructive Sleep ApneaThis study focuses on the prevalence and identification of kidney disease among participants of the WTC Health Program and the study team are planning to assess kidney disease in a multi-factorial manner. The first aim of this study is to correlate kidney dysfunction with 9/11 exposure, and the study team predicts that exposure to 9/11 is an independent risk factor in kidney disease among the WTC Health Program participants. Secondly, the study team proposes that a well-established WTC-related condition, obstructive sleep apnea (OSA), is independently associated with kidney disease. In addition, the study team believe there is a temporal causative relationship between evidence of kidney disease and the severity of OSA. Finally, the last aim is to further identify and explore potential mechanisms and phenotypes of kidney disease in participants of the WTC Health Programs. Regardless of whether the analyses support or reject these hypotheses, the findings will be of equally great public health importance. Successful completion of the proposed research would address a critical knowledge gap regarding the risk of kidney damage among this group of patients, and would inform future mechanistic studies with the potential to impact prevention.
Assessment of Renal Changes in Patients With Non Alcoholic Fatty Liver Disease
Non-Alcoholic Fatty Liver DiseaseChronic Kidney DiseasesAssess the renal changes in patients with non-alcoholic fatty liver (NAFLD).
a-Klotho in Relation to Calcification in the Coronary Arteries and Aortic Valve in Patients With...
Vascular CalcificationChronic Kidney DiseasesTo define the correlation of the levels of a-Klotho with the severity of vascular calcification in the coronary arteries and aortic valve.
Skin Autofluorescence as a Risk Marker in People Receiving Dialysis.
Chronic Kidney DiseaseThe purpose of the present study is to investigate the association between the accumulation of advanced glycation end-products (AGE) and adverse outcomes (e.g. death) in people receiving haemodialysis and peritoneal dialysis based in Royal Derby Hospital, as well as the impact of a dietetic intervention on AGE accumulation. AGE will be measured non-invasively in the skin using a technique called skin autofluorescence (SAF). The present study will be conducted in two parts: Study 1: this will be a prospective study where participants will be followed-up for up to five years. The research team will measure the accumulation of AGE in the skin using a quick (less than five minutes) and painless technique called SAF. This involves placing the forearm on a piece of equipment that shines a light on the skin and measures the amount of light that is reflected back. Participants will be asked to complete nutritional and quality of life questionnaires, measurements of weight, height, arm circumference and skinfold thickness (i.e. anthropometry), simple eyesight tests and blood tests. Study 2: observational non-randomized proof of principle study where malnourished dialysis participants will receive a dietitian supervised intensive nutritional support. Participants will be followed-up for 2 years and will receive precise oral and written instructions on how to comply with the intervention. Blood and eyesight tests, SAF measurements, anthropometry and nutritional and quality of life assessments will be conducted. In Studies 1 and 2, approximately two teaspoons of blood will be collected to measure AGE levels and do some additional blood tests to help us investigate the effects of AGEs on the body. If the participants agree, the investigators will also store some of the blood for future research.
Transcatheter Implantation of Aortic Bioprosthesis Without the Use of Iodinated Contrast in Patients...
Stenosis; ValveRenal Failure1 moreAcute renal failure (ARF) after transcatheter aortic valve implantation (TAVI) is a frequent complication, with significant clinical consequences. History of chronic kidney disease and the use of a large amount of iodinated contrast for planning and procedure are among the main risk factors for the development of this complication. The present study aims to: (1) define the role of non-contrast imaging modalities in pre-procedure planning; (2) evaluate the feasibility and safety of a new TAVI technique without using iodinated contrast; (3) to determine the incidence of acute renal failure in patients with aortic stenosis and chronic kidney disease undergoing TAVI, using the new technique without contrast. The study will be divided into two stages. In the pilot phase, 25 consecutive patients with chronic kidney disease (stage ≥ 3a) will have the TAVI planning and procedure performed without the use of iodinated contrast, but with all the steps subjected to verification by the standard technique, to ensure the safety of the patient. The occurrence of the combined primary safety outcome composed of adverse clinical events within 30 days (defined by the VARC-2 criteria) in less than 20% of cases will be used to define the continuity of the study. In the second phase, 50 patients with chronic kidney disease stage ≥ 3b will be submitted to TAVI with the "zero contrast" technique. The primary outcome assessed at this stage of the study will be the incidence of AKI within 7 days after TAVI using the new technique in this high-risk population.
The REnal Patients COVID-19 VACcination Immune Response (RECOVAC IR) Study
Covid19Chronic Kidney DiseasesRationale: COVID-19 is associated with severely increased morbidity and mortality in patients with severely impaired kidney function, on dialysis or alive with a kidney transplant. Therefore, effective SARS-CoV-2 vaccination would be of great clinical importance in these patients. However, SARS-CoV-2 vaccination studies have excluded patients with chronic kidney disease (CKD) so-far. Objective: To assess the efficacy and safety of SARS-CoV-2 vaccination in patients with CKD stages 4/5, on dialysis or alive with a kidney transplant as compared to controls. Study design: prospective, controlled multicenter study Study population: 175 patients with CKD stages 4/5 (eGFR < 30 ml/min/1.73m2), 175 on dialysis , 300 alive with a kidney transplant and 200 controls (partners or sibblings of patients) Intervention: SARS-CoV-2 vaccination according to standard of care. Blood will be drawn at 4 different time points (baseline and at day 28, month 6 and in a subset 28 days after a third vaccination). Main study parameters/endpoints: The primary endpoint is the antibody based immune response on day 28 after the second vaccination. Participants will be classified as responders or non-responders based on a spike (S)1 specific antibody levels of >=10 or <10 BAU/mL. The percentage of responders of each patient cohort will be compared with the percentage responders in the control group. Safety is a secondary endpoint which will be reported in terms of percentage of solicited local and systemic adverse events (AEs)graded according to severity. Other secondary endpoints include longevity of the immune response at 6 months, antibody respons 28 days after a third vaccination and levels of SARS-CoV-2 specific T and B cell responses.