Late aortic root dilatation in tetralogy of Fallot may be prevented by early repair in infancy.

The objectives of this study were to examine the relative contributions of development and hemodynamics in aortic root dilatation of tetralogy of Fallot, to assess the impact of systemic to pulmonary artery shunt on aortic annular size, and to seek any relationship between the timing of corrective surgery and subsequent aortic root size. We performed a retrospective analytical study at a tertiary referral center of M-mode and two-dimensionol aortic root measurements in children with tetralogy of Fallot prior to any surgical or palliative intervention, after insertion of a surgical shunt, and on intermediate and long-term follow-up post-repair. The main outcome measures were aortic root diameter prior to correction, after palliative shunt insertion, and after definitive repair. The study found that the aortic root is enlarged in unrepaired tetralogy of Fallot irrespective of age, increased in the first 3-6 months after palliative shunt surgery, and persisted into adulthood in those repaired after 1 year of age. Age-corrected aortic root dimensions normalized by mid-childhood in those who were repaired in infancy. Preexisting aortic root dilatation normalizes by 7 years of age in patients with tetralogy of Fallot who have been repaired in infancy, whereas it persists into adulthood in the group repaired post-infancy.