Pharmacokinetic/Pharmacodynamic Study of Udenafil in Adolescents

This is an interventional treatment trial for Single Ventricle Heart Disease After Fontan Surgery focused on measuring Fontan, Pharmacokinetics, Pharmacodynamics, Exercise capacity, Maximal Oxygen Consumption, Vascular function, EndoPAT, Myocardial performance Read More

Inclusion Criteria:

1. Males and females with Fontan physiology who are 14-18 years of age.
2. Willingness to return to center to complete blood draws and exercise tests as described in the study protocol.
3. Patients must agree to abstain from alcohol, caffeinated beverages, and grapefruit juice for the duration of the trial.
4. Informed assent from subject informed consent from parent/legal guardian as appropriate.

Exclusion Criteria:

1. Non-cardiac medical, psychiatric, and/or social disorder that would prevent successful completion of planned study testing or would invalidate its results.
2. Height <132 cm (minimum height requirement for exercise stress testing).
3. Known Fontan baffle obstruction, branch pulmonary artery stenosis, or pulmonary vein stenosis resulting in a mean gradient of >4 mmHg between the regions proximal and distal to the obstruction.
4. Single lung physiology.
5. Severe ventricular dysfunction or valvular regurgitation (systemic atrioventricular or semilunar valve) determined from review of the echocardiogram performed in closest proximity to study enrollment.
6. Significant renal (serum creatinine > 2.0), hepatic (serum aspartate aminotransferase (AST) and/or alanine aminotransferase ( ALT) > 3 times upper limit of normal), gastrointestinal or biliary disorders that could impair absorption, metabolism or excretion of orally administered medications, based on laboratory assessment at the time of screening visit.
7. Hospitalization for acute decompensated heart failure within the 12 months preceding study enrollment.
8. A diagnosis of active protein losing enteropathy or plastic bronchitis.
9. Active evaluation or listing for heart transplant.
10. History of use of a phosphodiesterase type 5 inhibitor within three months of study enrollment.
11. Concurrent illness that, in the opinion of the investigator, precludes participation.
12. Current therapy with alpha-blockers or nitrates.
13. Pregnancy at the time of enrollment.
14. Latex allergy