Heart failure or heart malformations are inherent defects in the heart or the vessels that carry blood in and out of the chamber of the heart. This occurs as a result of abnormal fetal development during the early part of pregnancy.
What leads to heart failure?
If a heart defect disrupts the baby’s blood flow, there may be a characteristic sound (murmur) which can be heard by a stethoscope.
In most of the countries, babies are born with a heart defect. Most heart malformations either obstruct the flow of blood into or out of the heart or cause blood to flow through the heart in an abnormal direction.
What causes a heart failure?
This is due by a heart malformation such as stenosis (a narrowing of an artery or valve leading to an obstruction of the blood flow). Heart defects that obstruct the blood flow include:
This is a narrowing of the aortic valve, through which blood flows from the left ventricle (one of the heart’s pairs of lower chambers) to the aorta (the large artery that distributes oxygenated blood to the body).
This is a narrowing of the pulmonary valve, through which blood flows from the right ventricle to the lungs.
This forces the right ventricle to pump harder to overcome the obstruction. In time, this causes enlargement and weakening of the ventricle.
Coarctation of the aorta:
In this, the aorta is constricted, obstructing blood flow to the lower part of the body and causing an increase in blood pressure above the constricted area.
- Cyanosis (bluish coloring of the skin), especially of the lips, fingers, and toes.
- Weakness and fatigue.
- Difficulty breathing.
- Poor feeding.
- Frequent squatting or assuming prominent positions to make breathing easier.
- Failure to grow at an appropriate rate.
Heart malformations in which blood flows in an important direction include:
Sometimes referred to as a ‘hole in the heart,’ this is an abnormal opening in the wall that separates the left and right sides.
These defects allow oxygenated and oxygen-depleted blood to mingle, thus decreasing the heart’s efficiency.
If the opening is in the wall between the heart’s upper chambers, it is called an atrial septal defect. An opening between the lower chambers is a ventricular septal defect.
The latter often accompanies coarctation of the aorta.
Patent ductus arteriosus:
In this, the ductus arteriosus (a passageway that allows blood to flow between the pulmonary artery and aorta before birth, but usually closes within a few hours afterward) remains open. It is quite common for premature babies but rare in full-term pregnancies.
Heart failure defects:
In these the blood is insufficiently oxygenated, leading to cyanosis, a blue discoloration of the skin. An infant with cyanosis is often called a ‘blue baby.’
One of the most common cyanotic defects, transposition of the great arteries, occurs when the aorta and pulmonary artery are reversed so that oxygen-depleted blood is continuously recirculated through the body, while oxygenated blood is returned to the lungs.
Another cyanotic defect, tetralogy of Fallot, is the result of four related malformations: a large ventricular septal defect; pulmonary stenosis; an enlarged right ventricle; and a displaced Aorta that lies over the hole between the two ventricles.
Less humble heart malformations are caused by the absence or underdevelopment of structures within the heart:
Tricuspid atresia: In this the valve that. Allows blood to flow from the right atrium to the right ventricle is absent.
Pulmonary atresia: Here the pulmonary valve, through which blood passes from the right ventricle to the pulmonary artery, fails to develop.
Hypoplastic heart: This occurs when the right or left side of the heart is not completely formed.
What causes heart malformations?
In all but a minority of cases, it is not known what causes heart defects. Sometimes the cause is part of an inborn abnormality, such as Down’s syndrome.
Sometimes the underlying cause is a virus. If a woman contracts German measles (rubella) during early pregnancy, the virus may interfere with the development of the baby’s heart and also produce other malformations.
Excessive alcohol consumption or exposure to toxins during pregnancy may also lead to the development of heart defects.
How are heart malformations diagnosed and treated?
Drugs may then be given to the mother (and hence to the baby) to help the heart work better.
Severe heart defects are usually found at birth or during early infancy. Sometimes an unusual sound (murmur) is heard in the heart, or cyanosis may be present.
Additional specialized diagnostic tests are usually necessary to determine the particular type of defect. Treatment may involve drugs, surgery or both.
Anyone with a heart malformation is at increased risk of developing bacterial endocarditis, a serious infection of the heart valves and the tissues lining the heart.
Such people may need to take antibiotics as a preventive measure before and after they undergo surgery or dental work.