KOCHI: Congenital heart defects (CHD) account for a major proportion of infant mortality globally. Eight out of 1,000 live born children have CHD and one-third of them constitute critical defects with high mortality and require treatment early in life.
The most common CHDs involve defects of the septa that separate the left and right side of the heart. Defective formation of the interventricular septum leads to ventricular septal defect (VSD), one of the diseases referred to as a “hole in the heart”. VSD is the most prevalent CHD at birth. One-third to half of them tend to close spontaneously in the initial years of life. Those with larger defects tend to present with breathlessness, feeding difficulty, poor weight gain and recurrent lower respiratory tract infections in infancy.
The cause of CHD is not clear but in some, it would be due to genetic and environmental factors. Atrial septal defects (ASD) and persistent ductus arteriosus (PDA) are some of the other “holes in the heart”. ASD is the commonest CHD in adult life. A significant proportion of small ASD closes spontaneously by five years of life. PDA is more common in premature infants and can cause heart failure in the newborn period. PDA does not regress in term infants and tends to persist. All of these defects are readily treatable in the current era. While some of the larger defects need surgical correction, the majority of them can be closed by transcatheter interventions in childhood.
Some of the critical heart diseases in childhood include defects that lead to ‘cyanosis’, or bluish discolouration of the body. These heart defects are mostly due to structural cardiac defects that permit deoxygenated blood to escape into the systemic circulation.
This is a life threatening defect early in infancy, and can be remedied by a surgery that reverts the arteries to their respective ventricles – the arterial switch operation. The majority of the critical heart diseases in children can be corrected by surgery in infancy.
Early detection of congenital heart diseases is of paramount importance for optimal management and to reduce morbidity and mortality associated with CHD. Not all heart diseases in children are present at birth.
Several diseases of the heart muscle can present at varying ages in infancy or childhood. Hypertrophic cardiomyopathy is a condition where the heart muscles are markedly thickened. Dilated cardiomyopathy is a condition with reduced cardiac muscle contractility leading to ventricular dysfunction and heart failure.
Dr Thomas Titus is an adult and paediatric cardiologist at Cosmopolitan Hospital, Pattom.
(The views expressed by the author are his own.)