Heart disease, congenital

Any abnormality of the heart present from birth. Defects may affect the heart chambers, valves, or main blood vessels. Major abnormalities are septal defects, coarctation of the aorta, transposition of the great vessels, patent ductus arteriosus, tetralogy of Fallot, hypoplastic left heart syndrome, pulmonary stenosis, and aortic stenosis. Developmental errors leading to defects arise early in the life of the embryo. In most cases, there is no known cause. Rubella in the mother is the most common known cause. The onset and severity of symptoms depend on the defect. Some anomalies cause cyanosis and breathlessness but others may go undetected. Possible complications of an untreated heart defect include impaired growth, pneumonia as a result of mild respiratory infections, rapid tiring during exercise, and Eisenmenger complex. Antenatal diagnosis, using specialized ultrasound scanning, is possible for most defects. After birth, any suspected defect is investigated using chest Xrays, ECG, or echocardiography. Oxygen and various drug treatments may improve the symptoms of heart block. Some conditions, such as small septal defects or patent ductus arteriosus, may get smaller or disappear of their own accord. Other defects will require surgical correction. Narrowed heart valves can often be treated by balloon valvuloplasty. In other cases, open heart surgery or a heart transplant may be required. Children with heart defects are at an increased risk of bacterial endocarditis; to prevent this, they are given antibiotic drugs before all surgical procedures including dental treatments.


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