Tetralogy of Fallot (TOF)
Tetralogy of Fallot is diagnosed in infancy and is characterized by the presence of several heart defects.
What is tetralogy of fallot?
Tetralogy of Fallot is a congenital heart defect, usually diagnosed in infancy. Tetralogy of Fallot is characterized by four malformations of the heart:
- Ventricular septal defect
- Pulmonary valve stenosis at or just below the pulmonary valve that partially blocks blood flow from the right side of the heart to the lungs
- Muscular right ventricle
- Aorta lying directly over the ventricular septal defect
Infants who have tetralogy of Fallot usually have cyanosis (bluish coloration of the skin due to low oxygen levels in the blood).
Babies diagnosed with tetralogy of Fallot must have corrective surgery. If left untreated, the condition can hinder growth and cause significant heart complications, disability and premature death. Children who have tetralogy of Fallot should be followed throughout their lives by a cardiologist who is experienced in treating congenital heart defects.
Many people who have had surgical repair of tetralogy of Fallot as children later develop a leaky pulmonary valve and require corrective heart valve surgery later in life.
Most adults who have tetralogy of Fallot will have had surgery to treat or repair the condition, although it is possible for the condition to remain undetected until adulthood.
Tetralogy of Fallot causes
Tetralogy of Fallot occurs during fetal development. Most of the time the cause is unknown, but factors that may play a role include:
- Poor nutrition
- Older maternal age
- Maternal alcoholism
- A parent with the condition
Tetralogy of Fallot may also be associated with DiGeorge Syndrome which is caused by a chromosomal abnormality.
Tetralogy of Fallot symptoms
Symptoms may include:
- Shortness of breath or rapid breathing
- Fainting
- Failure to thrive
- Fatigue
- Irritability
- Heart murmur
- Rounding of the fingernails and toenails
Tetralogy of Fallot diagnosis
At Ohio State, we ensure that each patient receives individualized care for their congenital heart defect. By creating a care team to diagnose and treat each case, we can better understand what steps will help patients get back to living their lives.
Tetralogy of Fallot treatment
Surgery is the only treatment for tetralogy of Fallot.
Surgery most often occurs between the ages of 18 and 36 months and consists of relieving the narrowing of the pulmonary valve, enlarging the main artery that carries blood to the lungs, and closing the hole between the bottom chambers of the heart (ventricular septal defect closure).
Some babies who are not yet ready for intracardiac repair surgery may have a temporary procedure in which a bypass between the aorta and pulmonary artery is created. Later, when the child has a complete repair, the bypass is removed.
There are several ways to treat the pulmonary valve stenosis malformation of tetralogy of Fallot including:
- Pulmonary valvotomy – the valve and surrounding tissue is removed which results in leakage. Many patients will require pulmonary valve replacement in late adolescence/early adulthood.
- Conduit/homograft placement – a pulmonary valve and main pulmonary artery replacement. As patients get older they may “outgrow” conduits. Conduits can also age and get calcium buildup. Either of these may require surgical repair.