Tetralogy of Fallot (TOF)
Tetralogy of Fallot (TOF) is a congenital heart condition characterized by a combination of four specific heart defects, which include ventricular septal defects, pulmonary valve stenosis, overriding aorta, and right ventricular hypertrophy. These abnormalities disrupt the normal flow of oxygen-rich blood, leading to symptoms such as bluish skin and nails, fatigue, fainting, and irritability, particularly in infants. TOF is typically diagnosed in infancy, although symptoms may emerge later in life. The exact causes of TOF remain uncertain, but factors such as maternal illness, malnutrition, genetic disorders, older maternal age, alcoholism, and family history may increase the risk during pregnancy.
Infants with TOF often experience "tet spells," episodes marked by a sudden drop in oxygen levels, which can be alarming and require immediate medical attention. Surgical intervention is usually necessary to correct the defects and improve the patient's quality of life. Most individuals who undergo surgery and appropriate treatments can lead relatively normal lives, but they will need regular medical evaluations and may need to limit certain physical activities to protect their heart's health. Understanding TOF is crucial for early detection and effective management of this potentially serious condition.
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Tetralogy of Fallot (TOF)
Tetralogy of Fallot (TOF) is a rare medical condition caused by a combination of four heart defects. These defects cause the heart to pump blood that does not contain enough oxygen, which the body needs. People affected by TOF may develop bluish skin and nails, become easily fatigued, or faint due to lack of oxygen. TOF and its contributory factors are congenital diseases that most often appear during infancy. The exact causes of TOF are unknown, but medical professionals believe the risk of TOF may be increased by illness, family history of the disease, alcoholism, and other factors in pregnant women. If detected early enough, TOF may be mostly corrected through surgery. People who receive surgery and other treatment for TOF have a good chance of leading relatively normal lives.
Overview
TOF is a condition caused by four related physical abnormalities in the human heart. (The word tetralogy refers to a combination of four.) These abnormalities are ventricular septal defects, pulmonary valve stenosis, overriding aorta, and right ventricular hypertrophy. People affected by these abnormalities have narrowing, hardening, misplacement, and gaps in the parts of the heart that move blood.
A properly functioning heart pumps blood that is rich in oxygen to other parts of the body. In people with TOF, the heart pumps blood that does not contain sufficient oxygen. This can lead to a variety of health problems, some of which may be life-threatening.
The defects that cause TOF are congenital, meaning that people are born with them already present. Health professionals are unsure of the exact causes of TOF, though it is likely more common in infants whose mothers experienced illness, malnourishment, or genetic disorders during pregnancy. Older age, alcoholism, and a family history of TOF are also likely contributing risk factors in pregnant women.
Symptoms of TOF usually appear in infants, though they may not appear until later in life. One of the main symptoms is a bluish tinge to the skin, which indicates that the blood is lacking oxygen. Other symptoms include fainting, shortness of breath, or fatigue that may inhibit regular activities such as feeding and playing. Infants with TOF may appear unusually irritable and have long crying spells. In addition, people with TOF may have physical symptoms including club fingers or toes or a heart murmur.
TOF often manifests in tet spells, or instances when a child's skin and nails suddenly take on a bluish color. Tet spells most often happen in children of about two to four months of age, and most often when their oxygen levels are altered by eating or crying. Tet spells may be dangerous, and parents should seek immediate medical help for children during these times.
Infants with TOF generally require surgery. Not undergoing surgery might cause the child to grow up with lingering and potentially deadly symptoms and complications. Fortunately, most cases of TOF can be largely corrected through surgery and treatment, though all people with TOF will require lifelong medical checkups and will likely have to restrict their physical activities to avoid overtaxing their hearts.
Bibliography
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