Fontan procedure Trials in Disease

Study on Sildenafil for Adults with Single Ventricle Heart Condition Post-Fontan Surgery

This clinical trial is investigating whether sildenafil can improve physical performance in adults who have undergone the Fontan operation. The Fontan procedure is a specialized heart surgery performed on people born with a functionally single ventricle, a condition where one of the heart's pumping chambers is underdeveloped. While the operation helps improve blood flow, patients often experience reduced exercise capacity and increased pressure in their veins over time.

Who can participate:

• Adults over 18 years of age
• Patients with a functionally univentricular heart who have undergone the Fontan operation
• Individuals in stable clinical condition who do not currently need cardiac catheterization (a procedure where a thin tube is inserted into the heart to check its function)
• Those willing to provide informed consent and understand the study requirements

Who cannot participate:

• Patients who have not had the Fontan operation
• Those who are not in stable clinical condition
• Patients who need cardiac catheterization
• Individuals under 18 years of age
• Those unable to take sildenafil as part of their treatment

What the trial involves:

The study focuses on determining whether adding sildenafil to current treatment can enhance physical performance in patients after the Fontan operation. Sildenafil works by relaxing blood vessels and improving blood flow throughout the body. Participants will receive either sildenafil (20 mg oral tablets) or a placebo for 24 weeks.

Throughout the study, researchers will conduct various tests to measure improvements, including:

• Ergospirometry tests to measure oxygen uptake during exercise
• 6-minute walk tests to evaluate walking distance and endurance
• Echocardiography to examine heart function
• Quality of life questionnaires

Regular monitoring will take place throughout the 24-week treatment period, with a final assessment at the end to measure changes in physical performance, exercise capacity, and overall quality of life.

Investigational drug: Sildenafil is being studied for its potential to improve physical performance in this patient population. As a phosphodiesterase type 5 (PDE5) inhibitor, it helps relax blood vessels and improve blood flow, which may benefit patients dealing with the unique circulation challenges created by the Fontan operation.