Respiratory morbidity in children with congenital heart disease.

Objective: To evaluate the respiratory outcome in children with congenital heart disease (CHD), considering recent management procedures and the CHD pathophysiology.

Design And Setting: Clinical and functional respiratory outcome were evaluated in 8-year-old children with isolated CHD followed up from birth in the prospective population-based EPICARD cohort.

Patients: Children were assigned to two groups, based on the pathophysiology of the CHD: CHDs with left-to-right shunt (n = 212) and CHDs with right outflow tract obstruction (n = 113).

Results: Current wheezing episodes were observed in 15% of the children with isolated CHD and left-to-right shunt, and 11% of the children with isolated CHD and right outflow tract obstruction (not significant). Total lung capacity (TLC) was the only respiratory function parameter that significantly differed between the two groups. It was lower in children with left-to-right shunt (88.72 ± 0.65% predicted) than in those with right outflow tract obstruction (91.84 ± 0.96, p = 0.006). In multivariate analysis, CHD with left-to-right shunt (coeff. [95% CI]: -3.17 [-5.45; -0.89]) and surgery before the age of 2 months (-6.52 [-10.90; -2.15]) were identified as independent factors associated with significantly lower TLC values.

Conclusion: Lower TLC remains a long-term complication in CHD, particularly in cases with left-to-right shunt and in patients requiring early repair. These findings suggest that an increase in pulmonary blood flow may directly impair lung development.