The Effects of Sildenafil on Exercise Function and Capacity in Patients With Fontan Circulation

The Effects of Sildenafil on Exercise Function and Capacity in Patients With Fontan Circulation

The study will test the hypothesis that a single dose of sildenafil can increase the exercise capacity of pediatric patients with a Fontan Circulation.

Inclusion Criteria:

• Age 6-17 years
• Male or female
• Possess Fontan Circulation

Exclusion Criteria:

• Severe heart failure (New York Heart Ass. functional class IV)
• Evidence of Fontan pathway obstruction
• History of exercise-induced severe arrhythmias
• Pregnancy (known or suspected)
• Orthopedic limitations that prevent ambulation on a treadmill
• Use of nitroglycerin
• Herbal medications