Congenital defects develop during the intrauterine life. Congenital heart defects are the most common type of defects present at the time of birth. Some congenital heart diseases cause no sign and symptom and may be diagnosed later in life when the child grows up. Congenital heart diseases may occur due to advance age of the mother or smoking or drinking during pregnancy or may be due to intake of some drugs. Infection by rubella can also lead to congenital heart defect in the new born.
Types of congenital heart diseases :
A. Acyanotic congenital heart diseases –
1. Ventricular Septal Defect
2. Atrial Septal Defect
3. Coarctation of Aorta
4. Patent Ductus Arteriosus
B. Cyanotic congenital heart diseases –
1. Tetrology of Fallot
2. Pulmonary Stenosis
VENTRICULAR SEPTAL DEFECT
It is the most common congenital heart disease. If the defect is small, it may be asymptomatic and spontaneous closure of the hole may occur. If the defect is large, it will lead to inadequate cardiac function. In this defect shunting of oxygenated blood from left ventricles to the right ventricles take place (due to the pressure gradient) which causes inadequate supply of oxygenated blood to the body. To add on this, venous returns being the same as usual, the amount of blood in right ventricle and pulmonary circulation increases hence increasing the load causing right ventricular hypertrophy, left atrium dilatation and pulmonary artery dilatation and later left ventricular hypertrophy. Pumping of more blood in the pulmonary circulation causes pulmonary vessel hypertrophy which leads to Reversal Of Shunt (from right ventricle to the left ventricle) also leading to Blue Baby (known as Eisen Manger Syndrome). Sometimes small defect can provide lodgement to bacterias causing infective endocarditis.
ATRIAL SEPTAL DEFECT
It is the 2nd most common congenital heart disease. In this defect shunting of oxygenated blood from left atrium to the right atrium occurs. As a result of this, body cells receive less amount of blood. This shunting increases load on the right atrium and the right ventricle causing Right Atrium Dilatation and Right Ventricular Hypertrophy. Pumping of more blood in the pulmonary circulation causes Pulmonary Vessel Hypertrophy which leads to Reversal Of Shunt and also leads to Blue Baby (Eisen Menger Syndrome).
COARCTATION OF AORTA
Coarctation means narrowing. It means narrowing of aorta. This reduces the amount of oxygenated blood to the organs supplied by the aorta after the narrowed part of aorta. Coarctation in aorta is seen after the branch of left subclavian artery. As a result of it, hands remain warm and red (proper blood supply) and legs become cold and pale (due to limited blood supply). At later phase, Upper body grows normally and the lower body becomes weak and growth is less as compared to hands. Radial pulse is strong but the femoral pulse is weak and blood pressure measured is high but legs are felt cold. It causes less blood supply to the kidneys leading to hematuria. It also causes less blood supply to intestine leading to blood in stool.
PATENT DUCTUS ARTERIOSUS
Ductus arteriosus is normal connection between pulmonary artery and the aorta during the intra uterine life which closes normally after birth. But if it fails to close, it is called patent ductus arteriosus. It causes shunting of oxygenated blood from aorta to the pulmonary artery causing less blood supply to the body. It also leads to more blood in the pulmonary circulation. It causes paleness in child, feeding activity by the child decreases and growth is also less. If shunting is too much, it causes heart failure (failure of heart to supply oxygenated blood to body and brain in adequate amount). It also provides place for the lodgement bacterias leading to infective endocarditis. Pumping of more blood in the pulmonary circulation causes Pulmonary Vessel Hypertrophy which leads to Reversal Of Shunt and also leads to Blue Baby ( Eisen Menger Syndrome).
TETROLOGY OF FALLOT
It is the commonest amongst cyanotic heart diseases. It consists of 4 heart defects –
• Pulmonary artery stenosis
• Ventricular septal defect
• Over riding of aorta (aorta placed over ventricular septal defect)
• Right ventricular hypertrophy
It causes a large amount of deoxygenated blood supplied to organs via the aorta. It also causes Blue Baby.
PULMONARY STENOSIS
This defect is cyanotic congenital heart disease. This defect is caused by the abnormal obstruction by pulmonary valve (semilunar valve). As force exerted by the right ventricle increases, it causes Right Ventricular Hypertrophy. Post Stenotic Dilatation also occurs due to forced entry of blood to the pulmonary artery.
Contributor- Medico Eshika Keshari
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