The diagnosis of Tetralogy of Fallot is frightening for parents who have infants with the disease, and rightfully so. Tetralogy of Fallot is a life-threatening condition that requires medical attention. However, there is also good reason for hope. The success rates for Tetralogy of Fallot surgery are greater than 95%. In this article, we will review the diagnosis and treatment for Tetralogy of Fallot and discuss the steps parents can take to improve outcomes after surgery.
What is Tetralogy of Fallot?
The complex term, Tetralogy of Fallot, is a bit easier to understand when it is broken down. Tetralogy simply means four (tetra-) and corresponds to the four clinical findings that occur in all patients with the disease. The defects that occur in Tetralogy of Fallot are:
- Ventricular septal defect (VSD) – An opening or hole between the two ventricles (larger chambers) of the heart
- Overriding aorta – The aorta is the major artery that leaves the left ventricle of the heart; an overriding aorta is caused by an enlarged aortic valve that seems to leave both the left and right ventricles
- Pulmonary stenosis – A stricture in the blood vessel that carries blood from the right ventricle to the pulmonary (lung) artery
- Right ventricular hypertrophy – To overcome these defects and pump at higher pressures, the muscle in the left ventricle thickens (hypertrophy)
Why Fallot? Arthur Fallot is the French doctor who first described the condition in great detail, and subsequently received credit for its name.
What are the symptoms of Tetralogy of Fallot?
The main symptoms of Tetralogy of Fallot are startling. The top of that list is cyanosis. Cyanosis is a bluing of the body. Blood (or more specifically hemoglobin) is red when it contains oxygen and blue when it does not. As the ductus arteriosus (a small, connecting blood vessel between a major artery and a major vein present during gestation and a little after birth) naturally closes, less and less blood circulates through the lungs (because of pulmonary stenosis, one of the four defects). With low oxygen levels in the blood, there is a blueish-purple tint to the skin, fingernails, lips, and tongue. The infant will be listless or (more often) irritable and fussy during one of these low oxygen spells. The baby’s body will try to get more oxygen by breathing faster; however, it is not a problem of air getting to the lungs, it is a problem of not enough blood reaching the lungs to receive oxygen. During these “Tet spells,” blood oxygen will be quite low. Blood oxygen is measured through a pulse oximeter, the device that attaches to a finger or in small infants, an arm.
How is Tetralogy of Fallot diagnosed?
Tetralogy of Fallot can be diagnosed in several ways. Your doctor may be able to hear a specific heart murmur using a stethoscope. The heart murmur is caused by whooshing blood flow through the defects in the heart. The baby may need to have an echocardiogram, which is a sonogram for the heart. Other procedures may be required (e.g., cardiac catheterization) to confirm the diagnosis or for surgical planning.
How is Tetralogy of Fallot treated?
The first goal in treating Tetralogy of Fallot is to stabilize the baby. One of the quickest ways to accomplish this is by administering supplemental oxygen. Supplemental oxygen by a tube in the nose or a face mask provides any blood that actually reaches the lungs to get a “superdose” of oxygen. This may or may not be enough to restore normal levels of oxygen to the blood. If it is not, a series of medications can be administered as needed. These include a pain medicine to help calm and comfort the baby and a beta blocker to slow down heart rate and ease its pumping burden. In more serious cases, a catheter may need to be inserted into the blood vessel system to temporarily improve blood flow to the lungs. The definitive treatment for Tetralogy of Fallot, however, is surgery.
Tetralogy of Fallot surgery
The surgery used to correct Tetralogy of Fallot is complex and technically challenging open-heart surgery, but most patients (~95%) have a successful outcome.1 In brief, the surgeons reverse the defects of Tetralogy of Fallot; they close the ventricular septal defect with mesh, increase blood flow to the lungs, and correct the overriding aorta. As an open-heart surgery, the rib cage must be opened to access the heart and lungs, but then closed at the end of surgery. Thus, the surgical wound is relatively large (and looks especially large on a small baby) and runs vertically down the center of the chest.
Parents are responsible for quite a lot after Tetralogy of Fallot surgery. The discharge instructions and care requirements can be quite involved. It is important that parents or caregivers follow feeding and activity recommendations carefully. Certain medications will be required and should be given regularly and on time, including and especially pain medications. It is also important to watch for changes in the baby’s status. Things like bluish or purplish skin, trouble breathing, unusual fussiness or signs of distress, or poor feeding should be reported to your doctor immediately. Consult your discharge instructions for a full list of worrisome symptoms.
Wound care after Tetralogy of Fallot surgery
Parents should make sure the wound that remains after Tetralogy of Fallot surgery is healing well and is free of infection. At each dressing check, check the wound for any bleeding, excess fluid, redness, or warmth. A slight redness around the surgical wound is normal soon after the surgery, but significant redness and warmth (and especially if the baby has a fever) could be signs of infection. Unless there is a drainage device left in place after surgery, the wound should be completely closed. It is normal for the surgical wound to be a little moist, but bleeding, green or yellow pus, or excessive fluid coming from the wound are all signs your doctor will want to hear about as they could indicate poor wound healing.
Dressings and dressing changes after Tetralogy of Fallot surgery
Parent or caregivers are responsible for the baby’s at-home dressing changes after Tetralogy of Fallot surgery. Each dressing change is an opportunity to check the wound for signs of healing or infection. Before discharge, ask your doctor or surgical team how to perform dressing changes. In fact, you can request some dressings and medical tape to take home. Many different types of dressings are available, and your medical team or wound nurse is an excellent resource. The ideal dressing is one that retains a bit of moisture to promote wound healing, but not so much that the moisture is excessive.
Medical tape after Tetralogy of Fallot surgery
Choosing a medical tape after Tetralogy of Fallot surgery is considerably easier than choosing a dressing. The top choice of medical tape for infants and young children is called Hy-Tape. Hy-Tape—better known in pediatric circles as Pink Tape—is particularly useful for wound dressings after Tetralogy of Fallot surgery. Hy-Tape’s adhesive contains zinc oxide, which is soothing to baby’s skin and releases cleanly during dressing changes. In fact, the biggest advantage Hy-Tape has over other medical tapes is that it is safe and gentle on the thin skin of infants. When Hy-Tape must be removed during a dressing change, it does not cause trauma to baby’s fragile skin. That said, Pink Tape is also strong enough to hold dressings in place, even when little hands try to grab and remove it.
Long term care after Tetralogy of Fallot surgery
While success rates from this type of surgery are high, close medical follow-up will be required for some time. This means visits to surgeons, cardiologists, and pediatricians. The patient may need additional surgeries and the heart may not function as well as it would have if it did not start out with the four defects. That said, almost all babies with Tetralogy of Fallot survive the procedure and life full lives.
1. Park CS, Lee JR, Lim HG, Kim WH, Kim YJ. The long-term result of total repair for tetralogy of Fallot. Eur J Cardiothorac Surg. 2010;38(3):311-317. 10.1016/j.ejcts.2010.02.030
Learn more about Hy-Tape and neonatal care.