Lung function in children with congenital heart disease

Abstract

Background: Congenital heart diseases (CHD) are frequently associated with abnormalities in pulmonary blood flow (PBF), which in turn can contribute to impaired lung development and increased respiratory morbidity. Lung function outcome was evaluated in children with CHD and prospectively followed from birth in the EPICARD cohort. Methods: Children with CHD associated with increased PBF (PBF+) or with decreased PBF (PBF-) were tested at age 8. Among each hemodynamic group, we identified CHD with spontaneous resolution between birth and 8 years (reference group); CHD still present at 8 years but never operated; operated CHD. Results: Two hundred and thirty-five PBF+ and 138 PBF- children had reliable LFT. When compared to the reference group, total lung capacity (TLC) was significantly decreased in operated PBF+ children (p=0.007) and in operated PBF- children (p=0.037). No decrease in FEV1/FVC ratio was measured. In the whole population, and after adjusting for age at surgery, sternotomy, wheezing, prematurity, and tobacco, increased PBF was significantly associated to decrease in TLC (coeff. -3.27; CI 95% -5.35--1.18). Among operated children, adjusted multivariate analysis identified age of surgery as significantly associated to a decrease in TLC, the youngest operated children having the lowest TLC values (coeff. 0.19; 0.05-0.33). Conclusions: Unexpectedly, CHD with increased PBF were associated with a worse lung function outcome than CHD with decreased PBF. If we consider that the age of surgery was largely related to the hemodynamic significance of CHD, we suggest that increased PBF induced impaired lung development that is proportional to the magnitude of the pulmonary flow. Support by French Ministry of Health and Abbvie