Impact of Chronic Hypoxia on Neurodevelopment of Children with Cyanotic Congenital Heart Disease

Document Type: Original article


1 Children’s Medical Centre, Paediatric Centre of Excellence, Tehran University of Medical Sciences (TUMS), Tehran, Iran

2 Shahid Beheshti University of Medical Sciences (SBMU), Tehran, Iran


Background: Children with cyanotic Congenital Heart Disease (CHD) are at higher risk for delay in their growth and development due to more energy consumption during their activities. In addition, they are more prone to respiratory infection and hospitalization. Due to the nature of disease, these patients suffer from a chronic hypoxia and its impact on growth and development is not well investigated. This study was designed to find out which physical growth and neurodevelopmental parameters of these patients are affected by chronic hypoxia in comparison with acyanotic disease.
Methods: 81 children with CHD (34 cyanotic and 47 acyanotic), aged between 6 months to 3 years from Children’s Medical Center affiliated to Tehran University of Medical Sciences in Tehran were recruited from January 2013 to January 2014. Growth parameters including weight, height, and head circumference were checked and then these indices were categorized into three groups of Failure To Thrive (FTT). Functional development was assessed by using modified Denver Developmental Screening Test (DDST II).
Results: In acyanotic group, Ventricular Septal Defect (VSD) and in the cyanotic group, tetralogy of fallot (TOF) were the most prevalent disorders. Growth indices were low in 52% of patients (70% of cyanotic and 38.2% acyanotic), and also weight and height parameters were significantly lower in the cyanotic group (p= 0.009 and p= 0.05).
62% of cyanotic patients and 17% of acyanotic patients had delay at least in one of their neurological development indices (Gross motor, fine motor, speech or psychosocial behavior). This study also demonstrates an association between neurodevelopment delay and FTT in cyanotic patients, but not in acyanotic ones.
Conclusion: Results in this study suggest that children with cyanotic CHD are more prone to delay in their development besides their growth possibly due to the nature of their disease. Therefore, chronic hypoxia can be a risk factor influencing neurodevelopment of the patients and appropriate intervention is required to gain better outcome.