Impact of Vitamin C on Endothelial Function and Exercise Capacity in Fontan-Palliated Patients

2014-08-27 03:19:29 | BioPortfolio


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.

Study Design

Allocation: Randomized, Control: Placebo Control, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment


Fontan Procedure


Vitamin C, Placebo


University of Michigan
Ann Arbor
United States




University of Michigan

Results (where available)

View Results


Published on BioPortfolio: 2014-08-27T03:19:29-0400

Clinical Trials [1321 Associated Clinical Trials listed on BioPortfolio]

Fontan Udenafil Exercise Longitudinal Assessment Trial

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...

Clinical Outcomes in Fenestrated Extra-Cardiac Fontan in Low Preoperative Risk Profiles

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...

Liothyronine in Children With Single Ventricle Congenital Cardiac Malformations Undergoing the Fontan Procedure

OBJECTIVES: I. Determine the pharmacokinetics of exogenous liothyronine administered in children undergoing the modified Fontan procedure. II. Determine the liothyronine supplementation...

Aspirin as a Novel Anti-Inflammatory Modality in the Fontan Patients

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...

Fontan Circulation and Cardiopulmonary Function: Prognostic Factors, Hemodynamics and Long-term Effects

Cross-sectional study of a national cohort of adolescents with univentricular congenital heart defects and Fontan type palliation.

PubMed Articles [4817 Associated PubMed Articles listed on BioPortfolio]

Hepatocellular Carcinoma as a complication of vascular disease of the liver after Fontan procedure.

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...

Augmentation of the pulmonary arteries at or prior to the Fontan procedure is not associated with worse long-term outcomes: a propensity-matched analysis from the Australia-New Zealand Fontan Registry.

Long-term data on the impact of pulmonary artery (PA) augmentation in patients who underwent the Fontan procedure are lacking. The aim of this study was to examine whether surgical or transcatheter PA...

Bone Microstructure in Response to Vitamin D3 Supplementation: A Randomized Placebo-Controlled Trial.

Vitamin D supplementation is often used in the prevention and treatment of osteoporosis, but the role of vitamin D has lately been questioned. We aimed to investigate the effect of 3 months of daily ...

Frontiers in Fontan failure: Innovation and improving outcomes: A conference summary.

The initial "Frontiers in Fontan Failure" conference in 2015 in Atlanta, GA, provided an opportunity for experts in the field of pediatric cardiology and adult congenital heart disease to focus on the...

Multimodality Screening of Hepatic Nodules in Patients With Congenital Heart Disease After Fontan Procedure: Role of Ultrasound, ARFI Elastography, CT, and MRI.

Currently, there is no consensus in the literature regarding the screening of hepatic nodules in patients who have undergone the Fontan procedure. The objectives of this study are to evaluate in this ...

Medical and Biotech [MESH] Definitions

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.

More From BioPortfolio on "Impact of Vitamin C on Endothelial Function and Exercise Capacity in Fontan-Palliated Patients"

Quick Search


Relevant Topics

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...

Searches Linking to this Trial