What Is Tetralogy of Fallot?
Tetralogy of Fallot (TOF) is a combination of four congenital heart defects that is treated with surgery.
It is a congenital heart defect that can be fatal if it’s left untreated. It’s also known as “tet.” The “tetra” in the name of the condition comes from the four problems associated with it. The condition is named after Dr. Etienne Fallot.
The main function of your heart is to pump blood through the rest of your body. This blood gives your body nutrients and oxygen. Sometimes, there are defects or problems with the heart when a person is born. These defects are known as congenital heart defects. If your heart doesn’t work properly, it may not be efficient in pumping blood to other organs. This affects the amount of oxygen getting to other bodily tissues.
The four heart defects associated with TOF are:
- a thickened right ventricle
- an aorta that has a shifted orientation and lays over the VSD
- a hole between the right and left ventricles, which is also called a ventricular septal defect (VSD)
- a narrow pulmonary outflow tract, which connects the heart with the lungs
The condition causes cyanosis. This means it causes the skin to have a bluish hue due to the lack of circulating oxygen. Typically, oxygenated blood gives the skin its pinkish hue.
Symptoms of Tetralogy of Fallot
The symptoms of TOF may be present at birth or shortly afterward. They include:
- failure to gain weight
- developmental delays or problems
- episodes of passing out
- problems with eating
- a bluish skin color
- clubbed fingers, or growths of skin and bone around the fingernails
Diagnosing Tetralogy of Fallot
Sometimes, a doctor will diagnose TOF while the baby is still in the mother’s uterus when a fetal ultrasound displays a heart abnormality. Your doctor can also diagnose it shortly after birth if they hear a murmur during a heart exam or if the baby’s skin color is bluish.
People most often receive a diagnosis in infancy, but if the defects aren’t severe, the symptoms may be minimal. This can delay diagnosis. Other times, the diagnosis comes later, such as when a parent notices something abnormal or during a regular visit to the pediatrician.
Tests that can aid in the diagnosis of TOF are:
- a pulse oximetry test to measure the oxygen level in the blood
- a heart MRI to check for structural problems
- a cardiac catheterization
- a chest X-ray to check for structural abnormalities
- an echocardiogram to check for disruptions in heartbeats
Causes and Risk Factors of Tetralogy of Fallot?
The exact cause of TOF is unknown, but several risk factors have been associated with the condition. These include:
- maternal alcoholism
- poor prenatal diet
- maternal age that’s over 40
People with TOF often have other congenital disorders such as Down syndrome.
Treatment for Tetralogy
Treatment of TOF requires surgery. This usually occurs within the first few months of life. The surgery includes closing the VSD and enlarging the pulmonary valve. According to the Children’s Hospital of Philadelphia, if doctors can’t perform a complete repair, they’ll perform a temporary repair until a complete surgery is possible.
If TOF is left untreated, it can cause problems with heart rhythms, developmental delays, and seizures. If the condition is never fixed, which is rare, it typically causes death by the age of 20 years old. Usually, a doctor will notice the condition early on and perform surgery to correct the problem.
After having surgery for TOF, a person will need to see a cardiologist for the rest of their life. A cardiologist will perform regular follow-up exams and consult with the person’s primary care physician on any medications or health problems that are present. Some people who have surgery for TOF develop heart problems as time goes on, which makes consistent and continuous care important.