Symptoms and causes of TOF

by Miguel Carlos

• The most common cause of Blue Baby Syndrome; and 
• The most common cyanotic heart defect.

The condition was named after Etienne-Louis Arthur Fallot, a French physician. TOF is more common in men than in women.

Tetralogy of Fallot Signs & Symptoms

Infants with TOF usually develop cyanosis during their first year of life. This includes:

• The lips, mucous membranes and the skin inside the mouth as well as the nose feature a noticeable dusky blue color.
• Infants with severe obstruction of the "right ventricle outflow" turning blue at night.
• If pulmonary stenosis is mild or if the ventricular septal defect is so small or even both, children with TOF never turn blue.
• Children whose cyanosis is subtle, the disease may go undetected for years. 

Symptoms of TOF are:

• A slower growth and development, especially if there is severe pulmonary stenosis. Even puberty can get delayed if left untreated.
• Child gets tired easily and starts panting at the slightest exertion. After playing for a very short time, the child will sit or lie down.
• When the child starts walking, he or she may assume a squatting position just to catch his or her breath before he resumes physical activity. This is since squatting can increase the pressure in the aorta as well as left ventricle transiently. If this is done, less blood flow will move to the left ventricle and more from the pulmonary artery towards the lungs. 
• During the first two to three years of life, the child may show episodes of extreme blue coloring. This is also referred to as "tet spells" or "hypercyanosis". During this stage:
• The child may feel a difficulty in breathing; he or she may turn blue; and he or she may become faint or extremely irritable. 
• These spells are usually experienced by 20% to 70% of children with TOF.
• These spells usually happen during crying, feeding, straining or during waking in the morning.
• These spells can last for a few minutes an even a few hours.

Tetralogy of Fallot Causes

TOF is perceived to be a result of genetic or environmental factors. There are times when it is a combination of these two factors. The condition is also associated with the DiGeorge syndrome and with chromosome 22 deletions. This also includes: NKX2-5, JAG1, ZFPM2 and VEGF.

(Tetralogy of Fallot is a combination of four congenital abnormalities. The four defects are a ventricular septal defect (VSD), pulmonary stenosis, a misplaced aorta and a thickened right ventricular wall (right ventricular hypertrophy). They usually result in an insufficient amount of oxygenated blood reaching the body.--Mayo Clinic Medical)

How a Congenital Heart Defect Develops

 by Josephine Osborn

How big is your heart?

The size of one's heart is roughly the size of one's fist. Whether as an infant or as one grows into adulthood, the size proportion is roughly the same. The heart is an essential organ of the body that one must take care of. Exercise, a clean lifestyle, a healthy diet and weight will go a long way in keeping your heart fit. There are instances though when one is born with a heart abnormality or, in medical parlance, a congenital heart defect.

What is a Congenital Heart Defect?

A congenital heart defect is an abnormality in the heart's structure that is present at birth. It may cause the blood flow to slow down, go in the wrong direction, go to the wrong place, or it may block the flow completely. Sometimes, they are referred to as cyanotic heart disease or congenital cardiovascular malformations.

Common Congenital Heart Defects

Heart defects are the most common of abnormalities at birth. About 35,000 infants are born with it each year in the United States. They may be simple defects with no symptoms to complex ones with life-threatening symptoms In fact, they are the leading cause of birth defect-related deaths. 

Simple congenital heart diseases include Atrial Septal Defect (ASD), Patent Ductus Arteriosus and narrowed valves. On the other hand, the most common complex heart defect is tetralogy of Fallot. It is a condition wherein not enough blood is able to reach the lungs to get oxygen, and oxygen-poor blood flows to the body. 

Causes

Environment and genes are contributory factors to developing a heart defect. More often than not though, the real cause is not identified. Drinking alcohol, smoking and use of cocaine during pregnancy can lead to heart defects. Other possible causes are medication, viral infections and chronic illnesses such as diabetes, phenylketonuria (PKU) and deficiency in the B vitamin folic acid. Heredity or genetic defects can also be predisposing factors. 

Prevention

Pregnancy is critical in the first trimester. The heart, like some other body organs, starts to develop shortly after conception. Chances of abnormal development or complications causing heart defects may happen.

Caution is advised when taking drug medication during pregnancy. Many drugs contain chemicals or substances that could potentially harm the fetus. Caution has been issued by the U.S. Food and Drug Administration (FDA) against usage of antidepressants among pregnant women. According to the FDA, studies showed that women who took Paxil during the first trimester of pregnancy were about 1.5 to two times as likely to have a baby with a heart defect as women who received other antidepressants. The issue of pre-natal drug medication, like the Paxil birth defect, is one that should not to be cast aside by any pregnant woman.