In this controlled trial, patients with tetralogy of Fallot will be randomized to either interval training, continuous training, or usual care groups.

Patients after surgical correction of tetralogy of Fallot (cTF) have impaired exercise tolerance as compared to healthy age-matched individuals. In this controlled trial, patients with cTF will be randomized to either interval training, continuous training, or usual care.

The aim of the study is to compare the effect of interval vs. continuous exercise training on:

i) exercise capacity ii) vascular function iii) arrhythmogenic potential iv) parameters of inflammation, hemostasis and heart failure severity v) health-related quality of life adults with cTF

Inclusion Criteria:

• congenital tetralogy of Fallot surgically corrected in childhood

Exclusion Criteria:

• contraindications for exercise training,
• uncontrolled dysrhythmias,
• uncontrolled heart failure (New York Heart Association (NYHA) stage IV),
• unstable coronary or other arterial disease,
• intellectual development disorder,
• pregnancy.