Septal defect

A congenital heart abnormality in which there is a hole in the septum between the left and right ventricles of the heart or, more rarely, between the left and right atria. Usually, the cause is unknown. The hole allows freshly oxygenated blood to mix with deoxygenated blood in the heart. A small defect has little or no effect. A large ventricular hole may cause heart failure to develop 6–8 weeks after birth, causing breathlessness and feeding difficulties. A large atrial defect may never cause heart failure, but there may be fatigue on exertion. Pulmonary hypertension may develop in both types of defect. Diagnosis may be aided by a chest X-ray, ECG, or echocardiography. Atrial holes are repaired surgically if they cause symptoms or if complications develop. As the child grows, small ventricular holes often become smaller, or even close, on their own. A ventricular defect that is causing heart failure is treated with diuretics and digitalis drugs. If the hole does not close spontaneously, it may be repaired by open heart surgery.