[Aptitude to physical effort in children with operated tetralogy of Fallot].

Abstract

Background: Long-term follow-up of patients after total surgical correction of tetralogy of Fallot indicates that they have a smaller working capacity than controls, with an increased incidence of late onset complete heart block and sudden death. These abnormalities may be less frequent when surgery is undertaken at an early age.

Population and methods: A cardio-pulmonary stress test was performed on 18 patients aged 8 to 20 years who had undergone correction of tetralogy of Fallot when they were 3 months to 7 years (mean age: 3 years). The basic ventilatory tests, exercise ventilatory tests and gas exchange were also performed.

Results: The cardiopulmonary stress test was maximal in 16 of the 18 cases. No stress-induced PVCs, or chronotropic insufficiency was found despite a basic long PR interval in 4 cases. A restrictive ventilatory syndrome was seen in 4 cases with low respiratory reserve at exercise (defined as the ratio between maximal observed ventilation and maximal theoretical ventilation, VEMS x 40). The respiratory function was normal in 14 cases with an aerobic capacity of over 40 ml/kg/min.

Conclusion: Patients with a normal chronotropic function and preserved aerobic capacity show no post-operative restriction or cardiac of pulmonary exercise capacity.