Track topics on Twitter Track topics that are important to you
In this study, investigators will evaluate the effect of vitamin C on endothelial function, exercise tolerance and quality of life in patients with a single ventricle who have been palliated to Fontan physiology. The hypothesis is that vitamin C will result in improved exercise tolerance and endothelial function in patients who have undergone the Fontan operation, compared to placebo.
Recent evidence suggests that after Fontan operation, single ventricle patients have impaired function of the vascular endothelium due in part to abnormalities in nitric oxide signaling. Endothelial dysfunction may contribute to the development of congestive heart failure and exercise intolerance that have been well-documented in Fontan patients. Therapeutic interventions to improve endothelial function in adults with heart failure have mainly focused on increasing the synthesis or decreasing the degradation of nitric oxide. We propose a randomized, prospective, placebo-controlled trial of vitamin C, an antioxidant that protects NO deactivation, in subjects with single ventricular anatomy after Fontan palliation. The specific aims of this study are to compare NO signaling, endothelial function and exercise capacity in Fontan subjects to that of a control group that is frequency-matched to case subjects by age and sex, and to assess NO signaling, endothelial function and exercise capacity in Fontan subjects after 4 weeks of oral vitamin C (or placebo) therapy. These results have particular importance because improving the endothelial response in Fontan patients has the potential to reduce the risk of developing congestive heart failure and improve exercise capacity. Furthermore, assessing endothelial function and the effects of therapies aimed at improving vascular health may be generalizable to many other chronic pediatric conditions associated with increased cardiovascular risk such as obesity, diabetes mellitus, and hypertension.
Allocation: Randomized, Control: Placebo Control, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment
Vitamin C, Placebo
University of Michigan
University of Michigan
Published on BioPortfolio: 2014-08-27T03:19:29-0400
This study will evaluate the clinical efficacy and safety of udenafil, an orally administered, potent and selective inhibitor of PDE5, versus placebo for the treatment of adolescent subjec...
Evaluation of fenestration benefit in Extra-cardiac total cavo-pulmonary connection (Fontan procedure) in single ventricle anomaly, comparing clinical outcomes of patients with low preoper...
OBJECTIVES: I. Determine the pharmacokinetics of exogenous liothyronine administered in children undergoing the modified Fontan procedure. II. Determine the liothyronine supplementation...
Patients who have undergone the Fontan procedure (a congenital heart surgery) may develop complications many years after their operation. Studies have shown that some of these patients dev...
Cross-sectional study of a national cohort of adolescents with univentricular congenital heart defects and Fontan type palliation.
Liver disease is a recognised complication of the Fontan procedure for cyanotic congenital heart disease. The Fontan procedure is a complex cardio-surgical procedure that diverts systemic venous blood...
History has shown that without explicit and enforced guidelines, even well-intentioned researchers can fail to adequately examine the ethical pros and cons of study design choices. One area in which c...
Transcatheter creation or enlargement of an atrial septal defect has been used to promote adequate blood flow and mixing in some forms of congenital heart defects or as a relief valve in right or left...
Low vitamin D status is associated with increased risk of pneumonia, greater disease severity and poorer outcome. However, no trials have examined the effect of adjunctive vitamin D therapy on outcome...
The objective of this article is to evaluate the potential effects of beta-glucan and vitamin D supplementation in patients with diabetic retinopathy. We evaluated the levels of several parameters of ...
A set of surgical procedures performed to establish sufficient outflow to the systemic circulation in individuals with univentricular congenital heart malformations, such as HYPOPLASTIC LEFT HEART SYNDROME, and MITRAL VALVE atresia, associated with systemic outflow obstruction. Follow-on surgeries may be performed and consist of a HEMI-FONTAN PROCEDURE as the stage 2 Norwood procedure and a FONTAN PROCEDURE as the stage 3 Norwood procedure.
A procedure in which total right atrial or total caval blood flow is channeled directly into the pulmonary artery or into a small right ventricle that serves only as a conduit. The principal congenital malformations for which this operation is useful are TRICUSPID ATRESIA and single ventricle with pulmonary stenosis.
A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: VITAMIN K 1 (phytomenadione) derived from plants, VITAMIN K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, VITAMIN K 3 (menadione). Vitamin K 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin K. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin K.
A nutritional condition produced by a deficiency of VITAMIN D in the diet, insufficient production of vitamin D in the skin, inadequate absorption of vitamin D from the diet, or abnormal conversion of vitamin D to its bioactive metabolites. It is manifested clinically as RICKETS in children and OSTEOMALACIA in adults. (From Cecil Textbook of Medicine, 19th ed, p1406)
OXIDOREDUCTASES which mediate vitamin K metabolism by converting inactive vitamin K 2,3-epoxide to active vitamin K.
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...
Blood is a specialized bodily fluid that delivers necessary substances to the body's cells (in animals) – such as nutrients and oxygen – and transports waste products away from those same cells. In vertebrates, it is composed of blo...
Benign Prostatic Hyperplasia (BPH) Erectile Dysfunction Urology Urology is the branch of medicine concerned with the urinary tract and diseases that affect it. Examples include urethritis, urethrostenosis and incontinence. Urology is a su...