OBJECTIVE: To identify mediators of health status and quality of life (QOL) in children and adolescents aged 8-18 years old following surgical repair for tetralogy of Fallot (TOF), including resource use, exercise performance, and 22q11.2 deletion status. STUDY DESIGN: We performed a corollary study to a cross-sectional analysis of subjects following repair for TOF that completed cardiac magnetic resonance imaging, cardiopulmonary exercise tests, and instruments assessing health status and QOL. General linear models were used to test for mediation. RESULTS: A total of 29 of 151 (19%) patients carried a 22q11.2 deletion. Parents of children with a deletion compared with those without a deletion reported worse physical and psychosocial functioning on the Child Health Questionnaire. The patients with a 22q11.2 deletion and their parents reported lower total and Disease Impact scores compared with the group without a deletion on the Pediatric Cardiac Quality of Life Inventory. Medical care use negatively correlated with measures of health status/QOL. Greater maximum work correlated with better patient health status and QOL, regardless of deletion status. Exercise performance mediated the association between deletion status and parent-reported outcomes (unstandardized effects ranging from 2.4 to 4.2) and patient-reported Disease Impact (0.99; 95% CI 0.02-2.70). CONCLUSION: Children and adolescents following repair for TOF seem to suffer significant challenges to their health status and QOL, which is amplified markedly in the context of the 22q11.2 deletion syndrome, and related to exercise performance.