Exercise capacity after repair of tetralogy of fallot in infancy

The long-term outcome of children after complete repair of tetralogy of Fal lot (ToF) has been well described.(1,2) Impairment in exercise tolerance ha s been frequently reported(3-6) and speculated to be due to a number of cau ses including residual right ventricular (RV) outflow tract obstruction,(7) branch pulmonary artery stenoses,(6) pulmonary insufficiency,(3,5,7-9) chr onotropic incompetence,(4) and pulmonary pathology.(10-12) Published report s have focused on children with an older age at repair.(1-5,7,10-14) Repair in infancy frequently necessitates placement of a transannular patch, and raises concerns as to the long-term effect of chronic pulmonary insufficien cy in those repaired at an early age. Although there is a growing body of p ublished data on those repaired in early childhood,(6,8) the long-term impa ct on aerobic capacity in those repaired during infancy remains unknown. We sought to assess long-term outcome of children with ToF repaired in infanc y (age >18 months), with an emphasis on cardiopulmonary exercise performanc e, and to identify any potential factors associated with impaired aerobic c apacity. In addition, we sought to compare exercise performance in children repaired in infancy with that in similar children who were repaired at an older age.