![Tetralogy of Fallot or TOF is a congenital (present since birth) heart defect that affects the normal flow of blood in the heart.](https://images.medicinenet.com/images/article/main_image/tetralogy-of-fallot.jpg?output-quality=75)
Tetralogy of Fallot or TOF is a congenital heart defect that affects the normal flow of blood in the heart.
Tetralogy of Fallot or TOF is a congenital (present since birth) heart defect that affects the normal flow of blood in the heart. According to the Centers for Disease Control and Prevention (CDC), around 1660 babies are born with this condition each year in the United States. Tetralogy of Fallot involves a defect in the heart structure that arises while the baby is still in the mother’s womb. The condition is characterized by the presence of four main defects in the structure of the heart:
- Ventricular septal defect: The heart has two upper chambers called atria and two lower chambers called the ventricles. The ventricles, right and left, are separated from each other by a partition called the interventricular septum. Ventricular septal defect or VSD refers to a defect or hole in the interventricular septum.
- Pulmonary stenosis: The pulmonary artery is the blood vessel that takes blood from the heart to the lungs for oxygenation. It is guarded by the pulmonary valve. An abnormal narrowing or obstruction in the pulmonary valve and the main pulmonary artery is called pulmonary stenosis.
- Overriding aorta: The aorta is the large blood vessel carrying the oxygen-rich blood from the heart to the body. It normally arises from the left ventricle. Overriding of the aorta means the aorta is situated abnormally. Such aorta arises above both the ventricles instead of just the left ventricle.
- Right ventricular hypertrophy: The abnormal thickening of the wall of the right ventricle is called right ventricular hypertrophy or RVH.
What are the symptoms of the tetralogy of Fallot?
The symptoms of tetralogy of Fallot may appear soon after birth or within the first year of life. The severity of symptoms may vary depending on the extent of the structural defects. The symptoms generally include:
- Cyanosis or bluish discoloration of the skin: It gets worse when the baby is crying or being fed (also known as a tet spell). Cyanosis is the most common symptom of TOF.
- Clubbing of fingers: This is a condition where the skin or bone around the fingernails becomes broad or rounded.
- Poor feeding habits: The baby is unable to suckle to the breast. The effort is too much for the baby.
- Poor weight gain or failure to gain weight
- Fainting episodes while playing
- Delayed milestones
- Easy fatiguability
- Irritability
- Difficulty in breathing
- Repeated flu infections and chest congestion
- Convulsions in a baby
What causes the tetralogy of Fallot?
The cause of tetralogy of Fallot is not known in most cases. Certain conditions may increase the risk of having tetralogy of Fallot. They include:
- Certain genetic conditions in the baby, such as Down syndrome, DiGeorge syndrome, and Alagille syndrome
- A history of alcoholism in the mother
- Presence of certain infections, such as rubella virus infection, during pregnancy
- Advanced maternal age (pregnancy in women aged older than 40 years)
- Maternal diabetes
- Certain medication taken during pregnancy
- Poor nutrition during pregnancy
- One of the parents having tetralogy of Fallot
How is the tetralogy of Fallot treated?
Tetralogy of Fallot is a type of critical congenital heart disease. Most babies require major surgery or other procedures soon after the birth. Most surgeries are done before the baby turns 6 months of age. The surgery involves widening or replacing the stenosed pulmonary valve and enlarging the lumen (inner diameter) of the pulmonary artery. The surgeon also repairs the ventricular septal defect with a patch. The outcome of most surgeries done for TOF is good. A regular follow-up with a cardiologist is necessary after the surgery. The individuals do well but have exercise restrictions all their life.
![](https://images.medicinenet.com/images/quiz/human-body/human-body-s1.jpg)
QUESTION
What percentage of the human body is water? See AnswerMancini MC. Tetralogy of Fallot. National Organization for Rare Disorders (NORD). https://rarediseases.org/rare-diseases/tetralogy-of-fallot/#:~:text=Tetralogy%20of%20Fallot%20consists%20of,right%20and%20left%20ventricles%20(dextroposition
Top What Are the 4 Defects in the Tetralogy of Fallot? Related Articles
Can Congenital Heart Defects Be Cured?
Congenital heart disease or a congenital heart defect is a medical condition that is present in an individual at birth. There are different types of congenital heart defects, ranging from simple conditions that don’t cause symptoms to complex ones that cause severe, life-threatening symptoms.Common Medical Abbreviations & Terms
Doctors, pharmacists, and other health-care professionals use abbreviations, acronyms, and other terminology for instructions and information in regard to a patient's health condition, prescription drugs they are to take, or medical procedures that have been ordered. There is no approved this list of common medical abbreviations, acronyms, and terminology used by doctors and other health- care professionals. You can use this list of medical abbreviations and acronyms written by our doctors the next time you can't understand what is on your prescription package, blood test results, or medical procedure orders. Examples include:
- ANED: Alive no evidence of disease. The patient arrived in the ER alive with no evidence of disease.
- ARF: Acute renal (kidney) failure
- cap: Capsule.
- CPAP: Continuous positive airway pressure. A treatment for sleep apnea.
- DJD: Degenerative joint disease. Another term for osteoarthritis.
- DM: Diabetes mellitus. Type 1 and type 2 diabetes
- HA: Headache
- IBD: Inflammatory bowel disease. A name for two disorders of the gastrointestinal (BI) tract, Crohn's disease and ulcerative colitis
- JT: Joint
- N/V: Nausea or vomiting.
- p.o.: By mouth. From the Latin terminology per os.
- q.i.d.: Four times daily. As in taking a medicine four times daily.
- RA: Rheumatoid arthritis
- SOB: Shortness of breath.
- T: Temperature. Temperature is recorded as part of the physical examination. It is one of the "vital signs."
Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.Diabetes Quiz
Take the Diabetes Quiz and learn the causes, signs, symptoms, and types of this growing epidemic. What does diabetes have to do with obesity and diet? Learn about life as a diabetic.Type 2 Diabetes Signs
Learn about type 2 diabetes warning signs, symptoms, diagnosis, and treatment options. Find out why thirst, headaches, and infections could be signs of diabetes. Discover the treatment options for people with type 2 diabetes, including medicines and lifestyle improvements.