Mayo Clinic Notes On Tof

TETRALOGY OF FALLOT

mayo clinic notes on tof

definition

tetralogy of fallot (fuh-loe) is an uncommon condition involving defects within the heart structures of infants and young children. together these defects result in oxygen-poor blood flowing out of the heart and into the body. consequently, infants and children with tetralogy of fallot usually have blue-tinged skin.

tetralogy of fallot is present at birth and usually diagnosed during infancy. however, it may not be detected until later in life, depending on the severity of the defects and symptoms. tetralogy of fallot occurs in about five out of every 10,000 babies. with early diagnosis followed by appropriate treatment, the majority of children with tetralogy of fallot live into adulthood.

symptoms

signs and symptoms of tetralogy of fallot vary, depending on the extent of obstruction of blood flow out of the right ventricle and into the lungs. typical signs and symptoms may include:

a bluish coloration of the skin caused by blood low in oxygen (cyanosis) shortness of breath and rapid breathing loss of consciousness (fainting) clubbing of fingers and toes (an abnormal, rounded shape of the nail bed) lack of appetite poor weight gain tiring easily during play irritability

tet spells infrequently, babies with tetralogy of fallot will suddenly develop deep blue skin, nails and lips after crying, feeding or upon awakening. these episodes are called "tet spells" and result from a rapid drop in the amount of oxygen in the blood. toddlers or older children may instinctively squat when they are short of breath. squatting increases blood flow to the lungs.

causes

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XDEEP NARAYAN J HA

MEDICAL INTERN

TETRALOGY OF FALLOT

tetralogy of fallot

tetralogy of fallot involves four ("tetra") defects within the heart structures of infants and young children. together these defects cause reduced blood flow to the lungs and mixing of blood from both sides of the heart. this results in oxygen-poor blood flowing out of the heart and into the body — usually resulting in blue-tinged skin (cyanosis) in infants and children with tetralogy of fallot.

a problem during fetal growth tetralogy of fallot occurs during fetal growth, when the baby's heart is developing. while factors such as poor maternal nutrition, viral illness or genetic disorders may increase the risk of this condition, in the majority of cases the cause of tetralogy of fallot is unknown.

tetralogy of fallot is named after a doctor who described four heart abnormalities common to several of his patients in 1888. this group of abnormalities includes:

pulmonary valve stenosis. this is a narrowing of the pulmonary valve, the flap that separates the right ventricle of the heart from the pulmonary artery, the main blood vessel leading to the lungs. constriction of the pulmonary valve reduces blood flow to the lungs.

ventricular septal defect. this is a hole in the wall that separates the two lower chambers (ventricles) of the heart. the hole allows deoxygenated blood in the right ventricle — blood that has circulated through the body and is en route to the lungs to replenish its oxygen supply — to flow into the left ventricle and mix with oxygenated blood fresh from the lungs. blood from the left ventricle also flows back to the right ventricle in an inefficient manner. this ability for blood to flow through the ventricular septal defect dilutes the supply of oxygenated blood to the body and eventually can weaken the heart.

overriding aorta. normally the aorta, the main artery leading out to the body, branches off the left ventricle. in tetralogy of fallot, the aorta is shifted slightly to the right and lies directly above the ventricular septal defect. in this position the aorta receives blood from both the right and left ventricles, mixing the oxygen-poor blood from the right ventricle with the oxygen-rich blood from the left ventricle.

right ventricular hypertrophy. when the heart's pumping action is overworked, it causes the muscular wall of the right ventricle to enlarge and thicken. over time this may cause the heart to stiffen, become weak and eventually fail.

the combined result of these abnormalities is that less blood reaches the lungs to pick up oxygen, more oxygen-poor blood is diverted into the left ventricle and the body fails to receive enough oxygenated blood.

risk factors

TETRALOGY OF FALLOT

while the exact cause of tetralogy of fallot is unknown, several factors may increase the risk of a baby being born with this condition. these include:

a viral illness in the mother, such as rubella (measles), during pregnancy maternal alcoholism poor nutrition a mother older than 40 a parent who had tetralogy of fallot

children born with down syndrome, a genetic condition resulting from an extra 21st chromosome, also are at increased risk of having tetralogy of fallot.

when to seek medical advice

seek medical help if you notice that your baby has the following symptoms:

difficulty breathing bluish discoloration of the skin passing out or seizures weakness unusual irritability

if your baby becomes blue (cyanotic), immediately place your child on his or her side and pull the knees up to the chest. this helps increase blood flow to the lungs. call 911 or your local emergency number immediately.

tests and diagnosis

after your baby is born, your baby's doctor may suspect tetralogy of fallot if the baby has blue-tinged skin or if a heart murmur — an abnormal whooshing sound caused by turbulent blood flow — is heard in your child's chest. by using several tests, your doctor can confirm the diagnosis.

chest x-ray. a typical sign of tetralogy of fallot on an x-ray is a "boot-shaped" heart, because the right ventricle is enlarged.

complete blood count. this is a test to measure the number of each type of cell in the blood. in tetralogy of fallot, the number of red blood cells may be abnormally high (erythrocytosis) as the body attempts to increase the oxygen level in the blood.

echocardiography. echocardiograms use high-pitched sound waves, inaudible to the human ear, to produce an image of the heart. sound waves bounce off your baby's heart and produce moving images that can be viewed on a video screen. this test is used to diagnose tetralogy of fallot by assessing whether a ventricular septal defect is present, the structure of the pulmonary valve, the function of the right ventricle and the position of the aorta.

TETRALOGY OF FALLOT

electrocardiogram. an electrocardiogram records the electrical activity in the heart each time it contracts. during this procedure, patches with wires (electrodes) are placed on your baby's chest, wrists and ankles. the electrodes measure electrical activity, which is recorded on paper. this test helps determine if your baby's right ventricle is enlarged (ventricular hypertrophy) and if the heart rhythm is regular.

cardiac catheterization. during this procedure, your doctor inserts a thin flexible tube (catheter) into an artery or vein in your baby's groin and threads it up to his or her heart. a dye is injected through the catheter to make your baby's heart structures visible on x-ray pictures. the catheter also measures pressure in the chambers of the heart and in the blood vessels.

complications

all babies with tetralogy of fallot need corrective surgery. without treatment, your baby may not grow and develop properly. he or she is also at increased risk of serious complications, such as infective endocarditis, an inflammation of the inner lining of the heart caused by a bacterial infection, or stroke, caused by a blood clot in the brain.

untreated cases of tetralogy of fallot usually develop severe complications over time, which may result in death or disability by early adulthood.

treatments and drugs

intracardiac repair tetralogy of fallot treatment for most babies involves a type of surgery called intracardiac repair. this surgery is typically performed during the first year of life. during this procedure, the surgeon places a patch over the ventricular septal defect to close the hole between the ventricles. he or she also repairs the narrowed pulmonary valve and widens the pulmonary arteries to increase blood flow to the lungs. after intracardiac repair, the oxygen level in the blood increases and your baby's symptoms will lessen.

occasionally babies need to undergo a temporary surgery before having intracardiac repair. if your baby was born prematurely or has pulmonary arteries that are underdeveloped (hypoplastic), doctors will create a bypass (shunt) between the aorta and pulmonary artery. this bypass increases blood flow to the lungs. when your baby is ready for a full repair, the shunt is removed.

after the surgery while most babies do well after intracardiac repair, complications are possible. the most frequent are chronic pulmonary regurgitation, in which blood leaks through the pulmonary valve, and an irregular heartbeat (arrhythmia). sometimes blood flow to the lungs is still restricted after intracardiac repair. babies with these complications may require another surgery, and in some cases, their pulmonary valves may be replaced by artificial valves. in addition, there's a slight risk of infection, unexpected bleeding or blood clots. arrhythmias are usually treated with medication.

TETRALOGY OF FALLOT

ongoing care after surgery your baby will require continuing care. your doctor will schedule routine checkups with your child to make sure that the procedure was successful and to monitor for any new problems.

your doctor may also recommend that your child limit physical activity or take antibiotics during dental procedures to prevent infections that may cause endocarditis, an inflammation of the lining of the heart. preventive antibiotics are recommended specifically for those who have artificial valves or who've had repair with prosthetic material.

prevention

while there's no known prevention for tetralogy of fallot, it's important to follow your doctor's advice about taking care of yourself during pregnancy. following a balanced diet and abstaining from alcohol and tobacco will increase the chances that your baby will be born healthy.

lifestyle and home remedies

if your baby has tetralogy of fallot, here are a few tips to help make your baby more comfortable:

feed your baby slowly. also give him or her smaller, more frequent meals. remain calm if your baby has a tet spell. this will reduce your child's anxiety. give yourself a break. ask other family members or friends to help you take care of

your child.

as your child grows, you may have some concerns about how best to care for your child, including:

preventing infection. a child with severe heart defects may need to take preventive antibiotics before certain dental and surgical procedures. your doctor will help you learn if this is necessary. maintaining good oral hygiene and getting regular dental checkups are excellent ways to help prevent infection.

exercising and play. parents of children with congenital heart defects often worry about the risks of rough play and vigorous activity even after successful treatment. although some children may need to limit the amount or type of exercise, many can lead normal or near-normal lives. your doctor can advise you about which activities are safe for your child.

coping and support

to help coordinate your child's care, you may wish to prepare a brief note with your child's diagnosis, medications, surgeries and their dates, and your cardiologist's name and number.

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this note will provide necessary information to others who may care for your child and will help any new doctor understand your child's health history.

if you change health insurance plans, be sure your new plan will cover your child's care, as some plans may not allow coverage for pre-existing conditions or may require a waiting period.

if you're an adult with congenital heart disease, you may have concerns, such as:

employment. having a congenital heart defect won't limit a person's career options in many cases. if an adult has serious heart rhythm problems or the potential for life-threatening complications, careers that may put others at risk may be discouraged, such as flying a plane or driving a bus.

pregnancy. most women with congenital heart disease can tolerate pregnancy without any problems. however, having a severe defect or complications such as chronic pulmonary regurgitation or arrhythmias can increase your risk of complications during pregnancy.

the risk of congenital heart disease in the general population is less than 1 percent. for children of parents with congenital heart disease, whether father or mother, this risk increases to between 2 percent and 20 percent, according to the american heart association. experts recommend that anyone with congenital heart disease who is considering starting a family, carefully discuss it beforehand with his or her doctor.

in some cases, preconception consultations with doctors who specialize in cardiology, genetics and high-risk obstetric care are needed. some heart medications can cause serious problems for a fetus and may need to be stopped or adjusted before you become pregnant.

emedicine note on tof

tetralogy of fallot overview

tetralogy of fallot is the most common heart defect in children. the condition causes mixing of oxygen-poor blood with the oxygen-rich blood being pumped out of the heart and into the circulatory system of blood vessels.

the blood leaving the heart has less oxygen than is needed by the organs and tissues of the body, a condition called hypoxemia.

chronic (ongoing, long-term) lack of oxygen causes cyanosis, a bluish color of the skin, lips, and membranes inside the mouth and nose.

the normal heart works as follows:

TETRALOGY OF FALLOT

the heart is made up of 4 chambers: 2 upper chambers called atria and 2 lower, larger chambers called ventricles. each atrium is separated from its paired ventricle by a valve.

the heart has a left and a right side. the left and right sides of the heart are separated by a septum (wall). the right side of the heart receives oxygen-depleted or blue blood returning by veins (superior vena cava and inferior vena cava) from the body.

the blood flows from the right atrium through the tricuspid valve into the right ventricle, which pumps it through the pulmonic valve into the pulmonary artery, the main artery to the lungs.

in the lungs, the blood absorbs oxygen and then returns to the left atrium through the pulmonary veins.

from the left atrium, the blood is pumped through the mitral valve to the left ventricle. the left ventricle pumps the blood out of the heart into the circulatory system via a large artery known as the aorta.

the blood moves throughout the body, supplying oxygen and nutrients to organs and cells.

organs cannot work properly if they do not receive enough oxygen-rich blood.

the 4 abnormalities (tetralogy) of the heart described by fallot include the following:

right ventricular hypertrophy: narrowing or blockage of the pulmonary valve and/or muscle under the pulmonary valve coming out of the right ventricle. this restriction to blood outflow causes an increase in right ventricular work and pressure, leading to right ventricular thickening or hypertrophy.

ventricular septal defect (vsd): this is a hole in the heart wall (septum) that separates the 2 ventricles. the hole is usually large and allows oxygen-poor blood in the right ventricle to pass through, mixing with oxygen-rich blood in the left ventricle. this poorly oxygenated blood is then pumped out of the left ventricle to the rest of the body. the body gets some oxygen, but not all that it needs. this lack of oxygen in the blood causes cyanosis.

abnormal position of the aorta: the aorta, the main artery carrying blood out of the heart and into the circulatory system, exits the heart from a position overriding the right and left ventricles. (in the normal heart, the aorta exits from the left ventricle.) this is not of major importance in infants.

pulmonary valve stenosis (ps): the major issue with tetralogy of fallot is the degree of pulmonary valve stenosis, since vsd is always present. if the stenosis is mild, minimal cyanosis occurs, since blood still mostly travels to the lungs. however, if the ps is moderate to severe, a smaller amount of blood reaches the lungs, since most is shunted right-to-left through the vsd.

TETRALOGY OF FALLOT

tetralogy of fallot accounts for 10-15% of all congenital (newborn) heart defects. infants with this abnormality develop signs of the condition very early in life.

tetralogy of fallot causes

tetralogy of fallot occurs during development of the fetus, before birth, and is therefore termed a congenital birth defect. an error occurs as the fetal heart separates into the chambers, valves, and other structures that make up the normal human heart. no one is really sure why this error occurs.

tetralogy of fallot symptoms

most infants with tetralogy of fallot develop cyanosis in the first year of life.

the skin, lips, and mucous membranes inside the mouth and nose take on a noticeably dusky blue color.

only some infants with very severe obstruction of the right ventricle outflow turn blue at birth.

a small number of children with tetralogy of fallot never turn blue at all, especially if the pulmonary stenosis is mild, the ventricular septal defect is small, or both.

in some children, the cyanosis is quite subtle and may go undetected for some time.

the following symptoms suggest tetralogy of fallot:

growth and development are slower, especially if the pulmonary stenosis is severe. puberty may be delayed if the tetralogy is untreated.

the child usually tires easily and begins panting with any form of exertion. he or she may play for only a short time before sitting or lying down.

once able to walk, the child often assumes a squatting position to catch his or her breath and then resumes physical activity. squatting increases the pressure transiently in the aorta and left ventricle, causing less blood to move into the left ventricle, more out the pulmonary artery to the lungs.

episodes of extreme blue coloring (called hypercyanosis or simply "tet spells") occur in many children, usually in the first 2-3 years of life.

the child suddenly becomes blue, has difficulty breathing, and may become extremely irritable or even faint.

up to 20-70% of children with tetralogy of fallot experience these spells.

TETRALOGY OF FALLOT

the spells often happen during feeding, crying, straining, or on awakening in the morning.

spells can last from a few minutes to a few hours.

when to seek medical care

sometimes tetralogy of fallot goes undiagnosed for several months to a year. diagnosing conditions such as tetralogy of fallot is one of the goals of routine checkups with your doctor. take your child to his or her health care provider if the child develops a bluish color, has breathing difficulties, seizures, fainting, fatigue, slow growth, or developmental delay. a medical professional should establish the cause of these problems.

if you cannot reach your child's health care provider or if the child develops any of the following symptoms, take the child to a hospital emergency department right away:

bluish discoloration

trouble breathing

seizures

fainting

extreme fatigue or weaknes

exams and tests

even if the bluish color and other symptoms have resolved by the time the child reaches medical attention, the health care provider will immediately suspect a heart problem. medical tests will focus on identifying the cause of the cyanosis.

lab tests: the red blood cell count and hemoglobin may be elevated as the body attempts to compensate for the lack of oxygen to the tissues.

electrocardiogram (ecg): this painless, quick test measures and records the electrical activity of the heart. structural abnormalities of the heart usually produce abnormal recordings on ecg. in tetralogy of fallot, right ventricular hypertrophy is almost always present.

chest x-ray imaging: this image may demonstrate the classic "boot-shaped heart." this occurs because the right ventricle is enlarged. it also may show an abnormal aorta.

echocardiography : this imaging test is key. it will demonstrate the ventricular septal defect or large hole between the left and right ventricles, the degree of pulmonary stenosis, and it will reveal other unanticipated defects. many patients do not need

TETRALOGY OF FALLOT

cardiac catheterization if the clinical, ecg, and echocardiogram findings are routine and as expected.

cardiac catheterization: this is an invasive procedure accomplished by a cardiologist in a special laboratory with the patient under local anesthesia. this procedure was done on all patients with suspected tetralogy prior to echocardiography, since it was the only procedure that could be used to confirm the diagnosis. if needed, a small tube (catheter) is inserted through the skin into a blood vessel (usually in the groin) and advanced up the inferior vena cava into the heart. an x-ray image is taken while a small amount of dye is infused. the dye helps highlight the ventricular septal defect, pulmonary stenosis, overriding aorta, and the size of the pulmonary arteries.

tetralogy of fallot treatment

self-care at home

if your child starts to turn blue, place the child on his or her back in the knee-to-chest position and call 911 or your local emergency numb

medical treatment

surgery is the primary way to correct the heart problem. your child may be prescribed medication for tet spells. you will also be given information for dealing with future tet spells.

the child will be placed on his or her back in the knee-to-chest position to increase aortic resistance. the increased aortic and left ventricular pressure reduces the rush of blood through the septal hole from the right ventricle and improves blood circulation to the lungs, so more red blood reaches the tissues.

the child may be given oxygen through a face mask to increase the amount of oxygen in the blood.

the child may be given morphine, propranolol (or metoprolol), or, in extreme cases, phenylephrine (alconefrin, vicks sinex). these medications decrease the frequency and severity of tet spells.

surgery

the blalock-taussig operation: a palliative procedure performed in smaller infants to increase blood flow to the lungs. this allows the child to grow big enough to have complete surgical repair.

a connection is made between one of the major arteries of the body, usually the right subclavian artery, and the right pulmonary artery, which increases the amount of red oxygenated blood reaching the lungs, relieving cyanosis with dramatic relief of the patient's symptoms.

TETRALOGY OF FALLOT

total correction: the hole in the ventricular septum (between the ventricles) is closed with a patch and the obstruction to right ventricular outflow, pulmonic stenosis, is opened. these corrections allow blood flow to the lungs for oxygenation before being pumped out into the body.

the timing of the operation depends on symptoms. surgery usually is performed within the first 2 years of life. operative mortality rates have dramatically dropped over the last 20 years. still, about 1-5% of children who undergo complete correction die during or immediately after the procedure, secondary to other additional defects in the body and/or heart, and the heart lung bypass procedure itself.

next steps

follow-up

your health care provider should schedule regular follow-up visits for your child. at these visits, the child should be checked for abnormal heart rhythms, which may develop in children who have undergone surgical correction for tetralogy of fallot.

outlook

after successful surgery, children generally don't have any symptoms and lead normal lives with few, if any, restrictions. however, the surgery itself may have some long-term complications. these include the following:

right ventricular failure: right ventricular failure is possible, especially if surgery created severe pulmonary valve insufficiency, that is regurgitation of blood backwards from the pulmonary artery into the right ventricle.

electrical conduction abnormalities: every patient with tetralogy of fallot has right bundle branch block secondary to the congenital ventricular septal defect. but sewing the patch into the ventricular septum can create heart block or failure of the upper atria to conduct/communicate with the lower ventricles. a permanent pacemaker is occasionally needed.

arrhythmias: because of surgery on the ventricles, postoperative ventricular tachycardia (vt) is an infrequent risk. this is a life-threatening arrhythmia, so follow-up detection of risk for ventricular tachycardia is important.

residual hole in the ventricular septum: this is also possible, with oxygenated blood passing from the left side of the heart to the right (shunting).

health science note on tof

TETRALOGY OF FALLOT

what is tetralogy of fallot?tetralogy (teh-tral-o-je) of fallot (fah-lo) is a congenital heart defect. a congenital heart defect is a problem with the heart's structure that’s present at birth. this type of heart defect changes the normal flow of blood through the heart.

tetralogy of fallot is a rare, complex heart defect that occurs in about 5 out of every 10,000 babies. it affects boys and girls equally.

to understand this defect, it's helpful to know how a healthy heart works. the diseases and conditions index how the heart works article describes the structure and function of a healthy heart. the article also has animations that show how your heart pumps blood and how your heart's electrical system works.

overview

tetralogy of fallot involves four heart defects:

a large ventricular septal defect (vsd) pulmonary (pull-mon-ary) stenosis right ventricular hypertrophy (hi-per-tro-fe) an overriding aorta

ventricular septal defect

the heart has a wall that separates the two chambers on its left side from the two chambers on its right side. this wall is called a septum. the septum prevents blood from mixing between the two sides of the heart.

a vsd is a hole in the part of the septum that separates the ventricles, the lower chambers of the heart. the hole allows oxygen-rich blood from the left ventricle to mix with oxygen-poor blood from the right ventricle.

pulmonary stenosis

this defect is a narrowing of the pulmonary valve and the passage through which blood flows from the right ventricle to the pulmonary artery.

normally, oxygen-poor blood from the right ventricle flows through the pulmonary valve, into the pulmonary artery, and out to the lungs to pick up oxygen. in pulmonary stenosis, the heart has to work harder than normal to pump blood, and not enough blood reaches the lungs.

right ventricular hypertrophy

TETRALOGY OF FALLOT

this defect occurs if the right ventricle thickens because the heart has to pump harder than it should to move blood through the narrowed pulmonary valve.

overriding aorta

this is a defect in the aorta, the main artery that carries oxygen-rich blood to the body. in a healthy heart, the aorta is attached to the left ventricle. this allows only oxygen-rich blood to flow to the body.

in tetralogy of fallot, the aorta is between the left and right ventricles, directly over the vsd. as a result, oxygen-poor blood from the right ventricle flows directly into the aorta instead of into the pulmonary artery to the lungs.

outlook

together, these four defects mean that not enough blood is able to reach the lungs to get oxygen, and oxygen-poor blood flows out to the body.

normal heart and heart with tetralogy of fallot

figure a shows the structure and blood flow in the interior of a normal heart. figure b shows a heart with the four defects of tetralogy of fallot.

babies and children who have tetralogy of fallot have episodes of cyanosis (si-a-no-sis). this is a bluish tint to the skin, lips, and fingernails. cyanosis occurs because the oxygen level in the blood is below normal.

TETRALOGY OF FALLOT

tetralogy of fallot must be repaired with open-heart surgery, either soon after birth or later in infancy. the timing of the surgery depends on how severely the pulmonary valve is narrowed.

over the past few decades, the diagnosis and treatment of tetralogy of fallot have greatly improved. as a result, most children who have this heart defect survive to adulthood. however, they’ll need lifelong medical care from specialists to help them stay as healthy as possible.

what causes tetralogy of fallot?doctors don't know what causes most cases of tetralogy of fallot and other congenital heart defects.

certain conditions or factors that occur during pregnancy may raise your risk for having a child with tetralogy of fallot. these conditions and factors include:

german measles (rubella) and some other viral illnesses poor nutrition overuse of alcohol age (being older than 40) diabetes

heredity may play a role in causing tetralogy of fallot. an adult who has tetralogy of fallot may have an increased chance of having a baby with the condition.

children who have certain genetic disorders, such as down syndrome and digeorge syndrome, often have congenital heart defects, including tetralogy of fallot.

scientists continue to search for the causes of tetralogy of fallot and other congenital heart defects.

what are the signs and symptoms of tetralogy of fallot?an important sign of tetralogy of fallot is cyanosis. cyanosis is a bluish tint to the skin, lips, and fingernails. low levels of oxygen in the blood cause cyanosis.

babies who have unrepaired tetralogy of fallot sometimes have “tet spells" in response to an activity like crying or having a bowel movement. a tet spell occurs when the oxygen level in the blood suddenly drops. this causes the baby to become very blue. the baby also may:

have a hard time breathing

TETRALOGY OF FALLOT

become very tired and limp not respond to a parent's voice or touch become very fussy lose consciousness

in years past, when tetralogy of fallot wasn't treated in infancy, children would get very tired during exercise and could faint. this heart defect is now repaired in infancy to prevent symptoms like this.

another common sign of tetralogy of fallot is a heart murmur. a heart murmur is an extra or unusual sound that doctors may hear while listening to the heart.

the sound occurs because the heart defect causes abnormal blood flow through the heart. however, not all heart murmurs are signs of congenital heart defects. many healthy children have heart murmurs.

normal growth and development depend on a normal workload for the heart and normal flow of oxygen-rich blood to all parts of the body. babies who have tetralogy of fallot may not gain weight or grow as quickly as children who have healthy hearts because they tire easily while feeding.

children who have tetralogy of fallot also may have clubbing. clubbing is the widening or rounding of the skin or bone around the tips of the fingers.

how is tetralogy of fallot diagnosed?doctors diagnose tetralogy of fallot based on a baby’s signs and symptoms, a physical exam, and the results from tests and procedures.

signs and symptoms of the heart defect usually occur during the first weeks of life. your infant's doctor may notice signs or symptoms during a routine checkup. some parents also notice cyanosis (a bluish tint to the skin, lips, and fingernails) or poor feeding and bring the baby to the doctor.

specialists involved

if your child has tetralogy of fallot, a pediatric cardiologist and cardiac surgeon may be involved in his or her care.

a pediatric cardiologist is a doctor who specializes in diagnosing and treating heart problems in children. cardiac surgeons repair heart defects using surgery.

physical exam

TETRALOGY OF FALLOT

during a physical exam, the doctor may:

listen to your baby's heart and lungs with a stethoscope. look for signs and symptoms, such as a bluish tint to the skin, lips, or fingernails and

rapid breathing. look at your baby’s general appearance. some children who have tetralogy of fallot

have characteristic facial traits because they have digeorge syndrome.

diagnostic tests and procedures

your child’s doctor may recommend several tests to diagnose tetralogy of fallot. these tests can provide information about the four heart defects that occur in tetralogy of fallot and how serious they are.

echocardiography

echocardiography (echo) is a painless test that uses sound waves to create a moving picture of the heart. during the test, the sound waves (called ultrasound) bounce off the structures of the heart. a computer converts the sound waves into pictures on a screen.

echo allows the doctor to clearly see any problem with the way the heart is formed or the way it's working.

echo is an important test for diagnosing tetralogy of fallot because it shows the four heart defects and how the heart is responding to them. this test helps the cardiologist decide when to repair these defects and what type of surgery is needed.

echo also is used to check a child's condition over time, after the defects have been repaired.

ekg (electrocardiogram)

an ekg is a simple, painless test that records the heart’s electrical activity. the test shows how fast the heart is beating and its rhythm (steady or irregular). it also records the strength and timing of electrical signals as they pass through each part of the heart.

an ekg also can help the doctor determine whether the right ventricle is enlarged (ventricular hypertrophy).

chest x ray

a chest x ray is a painless test that creates pictures of the structures in the chest, such as the heart and lungs. this test can show whether the heart is enlarged or whether the lungs have extra blood flow or extra fluid, a sign of heart failure.

pulse oximetry

TETRALOGY OF FALLOT

for this test, a small sensor is attached to a finger or toe (like an adhesive bandage). the sensor gives an estimate of how much oxygen is in the blood.

cardiac catheterization

during cardiac catheterization (kath-e-ter-i-za-shun), a thin, flexible tube called a catheter is put into a vein in the arm, groin (upper thigh), or neck and threaded to the heart.

special dye is injected through the catheter into a blood vessel or a chamber of the heart. the dye allows the doctor to see the flow of blood through the heart and blood vessels on an x-ray image.

the doctor also can use cardiac catheterization to measure the pressure and oxygen level inside the heart chambers and blood vessels. this can help the doctor determine whether blood is mixing between the two sides of the heart.

how is tetralogy of fallot treated?tetralogy of fallot must be repaired with open-heart surgery, either soon after birth or later in infancy. the goal of surgery is to repair the four defects of tetralogy of fallot so the heart can work as normally as possible. repairing the defects can greatly improve a child's health and quality of life.

the pediatric cardiologist and cardiac surgeon will decide the best time to do the surgery. their decision will be based on your baby's health and weight, how severe the defects are, and how severe your baby's symptoms are.

sometimes, teenagers or adults who had tetralogy of fallot repaired in childhood need additional surgery to correct heart problems that develop over time. see “living with tetralogy of fallot” for more information.

types of surgery

complete intracardiac repair

surgery to repair tetralogy of fallot is done to improve blood flow to the lungs and to make sure that oxygen-rich and oxygen-poor blood flows to the right places. the surgeon will:

widen the narrowed pulmonary blood vessels. the pulmonary valve is widened or replaced, and the passage from the right ventricle to the pulmonary artery is enlarged. these procedures improve blood flow to the lungs. this allows the blood to get enough oxygen to meet the body's needs.

TETRALOGY OF FALLOT

close the ventricular septal defect (vsd). a patch is used to cover the hole in the septum. this patch stops oxygen-rich and oxygen-poor blood from mixing between the ventricles.

fixing these two defects resolves problems caused by the other two defects. when the right ventricle no longer has to work so hard to pump blood to the lungs, it will return to a normal thickness. fixing the vsd means that only oxygen-rich blood will flow out of the left ventricle into the aorta.

the incision (cut) that the surgeon makes to reach the heart usually heals in about 6 weeks. the surgeon or a hospital staff member will explain when it's okay to give your baby a bath, pick him or her up under the arms, and take your baby for his or her regular shots (immunizations).

temporary or palliative surgery

it was common in the past to do temporary surgery during infancy in babies who had tetralogy of fallot. this surgery improved blood flow to the lungs. a complete repair of the four defects was done later in childhood.

now, most babies who have tetralogy of fallot have their defects fully repaired in infancy. however, some babies are too weak or too small to have the full repair. they must have temporary surgery first. this surgery improves oxygen levels in the blood. it also gives the baby time to grow and get strong enough for the full repair.

in the temporary surgery, the surgeon places a tube called a shunt between a large artery branching off the aorta and the pulmonary artery. one end of the shunt is sewn to the artery branching off the aorta. the other end is sewn to the pulmonary artery.

the shunt creates an additional pathway for blood to travel to the lungs to get oxygen. the shunt is removed when the baby's heart defects are fixed during the full repair.

after temporary surgery, your baby may need medicines to keep the shunt open while waiting for the full repair. these medicines are stopped after the shunt is removed.

living with tetralogy of fallotthe outlook for a child born with tetralogy of fallot is much better today than in the past. advances in testing and treatment mean that most children who have this congenital heart defect survive to adulthood. however, they need long-term care from specialists to stay as healthy as possible.

caring for your child at home

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feeding and nutrition

babies who have tetralogy of fallot can tire while nursing or feeding. small, frequent meals may be easier for your baby to handle.

your child also may need extra nutrition. a supplement or an extra feeding can give the baby more calories, vitamins, or iron. your child's doctors will work with you to determine what extra nutrition your baby needs.

tet spells

“tet spells” can occur in babies whose tetralogy of fallot hasn’t yet been repaired. lowering your baby's anxiety or stress can help prevent tet spells and save the baby's energy. for example, slowly picking up your baby and speaking in a soothing voice can avoid startling him or her, which may prevent or reduce crying.

talk to your doctor about how you can manage your child’s tet spells. your doctor may suggest that you:

bring the child's knees up tight against his or her chest (this is called the knee–chest position) or have your child squat down. this will increase blood flow to the lungs.

try to calm your child. call 9–1–1 if the symptoms don't improve right away.

activity restrictions

some children who have tetralogy of fallot may need to limit certain types of physical activity. the limits vary with each child. talk to your child’s doctor about whether:

your child needs to restrict activity or exercise your child can play in organized sports, especially contact sports you need a note for your child’s school or coaches about limiting your child's exercise

ongoing medical care

children who have tetralogy of fallot should have ongoing medical care. this includes:

seeing a pediatric cardiologist for heart checkups as directed seeing a pediatrician or family health care provider for routine exams making sure your child takes medicines as prescribed

children who have severe heart defects, like tetralogy of fallot, may be at slightly increased risk for infective endocarditis (ie). ie is a serious infection of the inner lining of your heart chambers and valves.

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in a few situations, your child's doctor or dentist may give your child antibiotics before medical or dental procedures (such as surgery or dental cleanings) that could allow bacteria into the bloodstream. your child’s doctor will tell you whether your child needs to take antibiotics before such procedures.

to reduce the risk of ie, gently brush your young child’s teeth every day as soon as they begin to come in. as your child gets older, make sure he or she brushes every day and sees a dentist regularly. talk with your child’s doctor and dentist about how to keep your child’s mouth and teeth healthy.

consider having your child wear a medical alert bracelet or necklace. this alerts anyone caring for your child that the child has tetralogy of fallot.

you may want to work with your health care providers to put together a packet of medical records and information that covers all aspects of your child's heart defect, including:

diagnosis procedures or surgeries prescribed medicines recommendations about medical followup and how to prevent complications health insurance

keeping your health insurance current is important. for example, if you plan to change jobs, find out whether your new health insurance will cover care for your child's congenital heart defect.

some health insurance plans may not cover medical conditions that were covered under a previous plan.

special needs for teenagers and adults

as children who have tetralogy of fallot grow up and become teens, it's important that they understand the condition, how it was treated, and what kind of care may still be needed.

this understanding will help them take responsibility for their health. it also will help ensure a smooth transition when they start getting care from a cardiologist instead of a pediatric cardiologist. a cardiologist treats adults who have heart problems.

it's also very important for teens to have health insurance as adulthood approaches. review your current health insurance plan. find out whether you can extend coverage to your child beyond the age of 18. some policies may allow you to keep your child on your plan if he or she remains in school or is disabled.

some teenagers or young adults need additional surgery. for example, the pulmonary valve can narrow again over time, reducing blood flow. the valve may need to be widened or

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replaced. the cardiologist will discuss with you and your teenager the need for any additional heart surgeries.

over time, people who have had surgery to repair tetralogy of fallot also may face a number of other heart problems.

leaking heart valves

the heart has four valves that open and close with each heartbeat. these valves ensure that blood flows in only one direction.

if a valve doesn't seal tightly, blood can leak back into the chamber it came from. this is called backflow or regurgitation (re-gur-ji-ta-shun), and it can lead to symptoms and complications.

the most frequent problem that occurs after tetralogy of fallot repair is pulmonary backflow, or leaking from the pulmonary valve. backflow from the tricuspid valve and aortic valve also can occur. surgery is needed to repair or replace the leaking valve.

arrhythmias

arrhythmias (ah-rith-me-ahs) are another complication that may develop. arrhythmias are problems with the rate or rhythm of the heartbeat.

arrhythmias linked to tetralogy of fallot include ventricular tachycardia, atrial fibrillation, and atrial flutter. for more information, see “types of arrhythmia.”

medicines are used to control these arrhythmias. medical procedures or surgery also may be needed to treat arrhythmias.

pulmonary artery branch stenoses

over time, the pulmonary valve can narrow again. this will reduce blood flow to the lungs, making the heart work harder than it should. several surgical techniques can be used to fix this problem.

right ventricular aneurysms

the patch used to fix the ventricular septal defect (vsd) can cause areas of the ventricle to weaken. the areas, called aneurysms (an-u-risms), can bulge or “balloon” out.

aneurysms make it hard for the heart to function as well as it should. this problem must be repaired with surgery.

residual ventricular septal defects

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sometimes, vsds still leak even after they’ve been repaired. vsds are repaired again if they’re large or are causing problems with the function of the right ventricle.

coronary heart disease

as people who have repaired tetralogy of fallot approach middle age, they can develop coronary heart disease (chd), just as adults who don’t have heart defects can.

chd, also called coronary artery disease, is a condition in which a fatty substance called plaque (plak) builds up in the coronary (heart) arteries. chd can lead to chest pain, shortness of breath, and heart attack.

preventing chd is especially important because the procedures done to relieve chd, like coronary artery bypass grafting, can cause complications in people who have repaired tetralogy of fallot.

other considerations

many women with repaired tetralogy of fallot who become pregnant are able to have successful, full-term pregnancies. others may have difficult pregnancies.

women with tetralogy of fallot who want to become pregnant (or who are pregnant) should talk to their doctors about:

health risks during pregnancy medicines they can take during pregnancy any new or worsening symptoms

these women also should consult specialists who take care of pregnant women who have heart conditions, such as congenital heart defects.

adults who were born with tetralogy of fallot should consider job changes carefully, because health benefits may change. some health plans have waiting periods or clauses to exclude some types of coverage. before making any job changes, find out whether the change will affect your health insurance.

several laws protect the employment rights of people who have health conditions, such as congenital heart defects. the americans with disabilities act and the work incentives improvement act try to ensure fairness in hiring for all people, including those who have health conditions.

key points tetralogy of fallot is a rare, complex congenital heart defect. a congenital heart defect is

a problem with the heart's structure that's present at birth.

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tetralogy of fallot involves four heart defects:o a large ventricular septal defect (vsd)o pulmonary stenosiso right ventricular hypertrophyo an overriding aorta

together, these four defects mean that not enough blood is able to reach the lungs to get oxygen, and oxygen-poor blood flows out to the body.

doctors don't know what causes most cases of tetralogy of fallot. certain conditions or factors that occur during pregnancy may raise your risk for having a child with tetralogy of fallot. heredity and some genetic disorders also may play a role in causing this condition.

an important sign of tetralogy of fallot is cyanosis. cyanosis is a bluish tint to the skin, lips, and fingernails. other signs and symptoms include a heart murmur, delayed growth and development, and clubbing. clubbing is the widening or rounding of the skin or bone around the tips of the fingers.

babies who have unrepaired tetralogy of fallot sometimes have “tet spells.” a tet spell occurs when the oxygen level in the blood suddenly drops. this causes the baby to become very blue. he or she also may have trouble breathing, become very tired and limp, not respond to a parent’s voice or touch, become very fussy, or lose consciousness.

doctors diagnose tetralogy of fallot based on a baby’s signs and symptoms, a physical exam, and the results from tests and procedures. signs and symptoms of the heart defect usually occur during the first weeks of life.

tetralogy of fallot must be repaired with open-heart surgery, either soon after birth or later in infancy. the goal of surgery is to repair the four defects of tetralogy of fallot so the heart can work as normally as possible.

surgery involves widening or replacing the pulmonary valve and enlarging the passage from the right ventricle to the pulmonary artery. this improves blood flow to the lungs. surgeons also close the vsd with a patch. the patch stops oxygen-rich and oxygen-poor blood from mixing between the ventricles. fixing these two defects resolves problems caused by the other two defects.

some babies who are very small or weak have a temporary procedure that improves blood flow to the lungs and gives the baby time to grow and get strong enough for the full repair.

advances in treatment mean that most children who are born with tetralogy of fallot survive to adulthood. however, these children need lifelong care from specialists to stay as healthy as possible.

teenagers and adults who had surgery to repair tetralogy of fallot may have long-term heart problems, such as heart function problems, arrhythmias (irregular heartbeats), or problems resulting from the original repair. these problems are treated with medicines, procedures, and surgery.

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cardiovascular disorders

tetralogy of fallot

what is tetralogy of fallot?

tetralogy of fallot (tof or "tet") is a complex condition of several congenital (present at birth) defects that occur due to abnormal development of the fetal heart during the first 8 weeks of pregnancy. these problems include the following:

click image to enlarge

ventricular septal defect (vsd) - an opening in the ventricular septum, or dividing wall between the two lower chambers of the heart known as the right and left ventricles.

pulmonary (or right ventricular outflow tract) obstruction - a muscular obstruction in the right ventricle, just below the pulmonary valve, that decreases the normal flow of blood. the pulmonary valve may also be small.

overriding aorta - the aorta is shifted towards the right side of the heart so that it sits over the ventricular septal defect.

"tetralogy" refers to four heart problems. the fourth problem is that the right ventricle becomes enlarged as it tries to pump blood past the obstruction into the pulmonary artery.

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click image to enlarge

normally, oxygen-poor (blue) blood returns to the right atrium from the body, travels to the right ventricle, then is pumped through the pulmonary artery into the lungs where it receives oxygen. oxygen-rich (red) blood returns to the left atrium from the lungs, passes into the left ventricle, and then is pumped through the aorta out to the body.

in tetralogy of fallot, blood flow within the heart varies, and is largely dependent on the size of the ventricular septal defect, and how severe the obstruction in the right ventricle is.

with mild right ventricle obstruction, the pressure in the right ventricle can be slightly higher than the left. some of the oxygen-poor (blue) blood in the right ventricle will pass through the vsd to the left ventricle, mix with the oxygen-rich (red) blood there, and then flow into the aorta. the rest of the oxygen-poor (blue) blood will go its normal route to the lungs. these children may have slightly lower oxygen levels than usual, but may not appear blue.

with more serious obstruction in the right ventricle, it is harder for oxygen-poor (blue) blood to flow into the pulmonary artery, so more of it passes through the vsd into the left ventricle, mixing with oxygen-rich (red) blood, and then moving on out to the body. these children will have lower than normal oxygen levels in the bloodstream, and may appear blue, especially whenever the pressure in the right ventricle is very high and large amounts of oxygen-poor (blue) blood passes through the vsd to the left side of the heart.

tetralogy of fallot makes up about 5 to 7 percent of all cases of congenital heart defects and occurs equally in boys and in girls.

what causes tetralogy of fallot?

some congenital heart defects may have a genetic link, either occurring due to a defect in a gene, a chromosome abnormality, or environmental exposure, causing heart problems to occur more often in certain families.

TETRALOGY OF FALLOT

maternal abuse of alcohol during pregnancy, leading to fetal alcohol syndrome (fas), is linked to tetralogy of fallot. mothers who take medications to control seizures and mothers with phenylketonuria (pku) are also more likely to have a baby with tetralogy of fallot.

most of the time, this heart defect occurs sporadically (by chance), with no clear reason evident for its development.

why is tetralogy of fallot a concern?

the amount of oxygen-poor (blue) blood that passes through the vsd to the left side of the heart varies. if the right ventricle obstruction is severe, or if the pressure in the lungs is high, a large amount of oxygen-poor (blue) blood passes through the vsd, mixes with the oxygen-rich (red) blood in the left ventricle, and is pumped to the body. the more blood that goes through the vsd, the less blood that goes through the pulmonary artery to the lungs, and the less oxygen-rich (red) blood that returns to the right side of the heart. soon, nearly all the blood in the left ventricle is oxygen-poor (blue). this is an emergency situation, as the body will not have enough oxygen to meet its needs.

some situations, such as crying, increase the pressure in the lungs temporarily, and increasing blueness might be noted as a baby with tetralogy of fallot cries. in other situations, the pathway from the right ventricle to the pulmonary artery becomes tighter, preventing much blood from passing that way, and allowing oxygen-poor (blue) blood to flow through the vsd into the left heart circulation. both of these situations are nicknamed "tet spells." sometimes, steps can be taken to lessen the pressure or the obstruction, and allow more blood to flow into the lungs and less through the vsd. these steps, however, are not always effective.

what are the symptoms of tetralogy of fallot?

the following are the most common symptoms of tetralogy of fallot. however, each child may experience symptoms differently. symptoms may include:

because large amounts of oxygen-poor (blue) blood can flow to the body under certain circumstances, one of the indications of tetralogy of fallot is blueness (blue color of the skin, lips, and nail beds) that occurs with such activity as crying or feeding, and quickly becomes more obvious.

some babies do not have noticeable cyanosis (blue color of the skin, lips, and nailbeds), but may instead be very irritable or lethargic due to a decreasing amount of oxygen available in the bloodstream.

some children become pale or ashen in color, and may have cool, clammy skin.

any of these can be symptoms of tetralogy of fallot. the symptoms of tetralogy of fallot may resemble other medical conditions or heart problems. always consult your child's physician for a diagnosis.

how is tetralogy of fallot diagnosed?

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your child's physician may have heard a heart murmur during a physical examination, and referred your child to a pediatric cardiologist for a diagnosis. a heart murmur is simply a noise caused by the turbulence of blood flowing through the obstruction from the right ventricle to the pulmonary artery. symptoms your child exhibits will also help with the diagnosis.

a pediatric cardiologist specializes in the diagnosis and medical management of congenital heart defects, as well as heart problems that may develop later in childhood. the cardiologist will perform a physical examination, listening to the heart and lungs, and make other observations that help in the diagnosis. the location within the chest that the murmur is heard best, as well as the loudness and quality of the murmur (harsh, blowing, etc.) will give the cardiologist an initial idea of which heart problem your child may have. however, other tests are needed to help with the diagnosis, and may include the following:

chest x-ray - a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.

electrocardiogram (ecg or ekg) - a test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and detects heart muscle stress.

echocardiogram (echo) - a procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves.

cardiac catheterization - a cardiac catheterization is an invasive procedure that gives very detailed information about the structures inside the heart. under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin, and guided to the inside of the heart. blood pressure and oxygen measurements are taken in the four chambers of the heart, as well as the pulmonary artery and aorta. contrast dye is also injected to more clearly visualize the structures inside the heart.

treatment for tetralogy of fallot treated:

specific treatment for tetralogy of fallot will be determined by your child's physician based on:

your child's age, overall health, and medical history extent of the condition your child's tolerance for specific medications, procedures, or therapies expectations for the course of the condition your opinion or preference

tetralogy of fallot is treated by surgical repair of the defects. a team of cardiac surgeons performs the surgery, usually before an infant is 1 year old. in many cases, the repair is made at around 6 months of age, or even a little earlier. repairing the heart defects will allow oxygen-poor (blue) blood to travel its normal route through the pulmonary artery to receive oxygen.

the operation is performed under general anesthesia, and involves the following:

TETRALOGY OF FALLOT

the ventricular septal defect is closed with a patch. the obstructed pathway between the right ventricle and the pulmonary artery is opened

and enlarged with a patch. if the pulmonary valve is small, it may be opened as well or removed.

postoperative care for your child:

children will spend time in the intensive care unit (icu) after tetralogy of fallot repair. during the first several hours after surgery, your child will be very drowsy from the anesthesia that was used during the operation, and from medications given to relax him/her and to help with pain. as time goes by, your child will become more alert.

while your child is in the icu, special equipment will be used to help him/her recover, and may include the following:

ventilator - a machine that helps your child breathe while he/she is under anesthesia during the operation. a small, plastic tube is guided into the windpipe and attached to the ventilator, which breathes for your child while he/she is too sleepy to breathe effectively on his/her own. after a truncus repair, children will benefit from remaining on the ventilator overnight or even longer so they can rest.

intravenous (iv) catheters - small, plastic tubes inserted through the skin into blood vessels to provide iv fluids and important medicines that help your child recover from the operation.

arterial line - a specialized iv placed in the wrist or other area of the body where a pulse can be felt, that measures blood pressure continuously during surgery and while your child is in the icu.

nasogastric (ng) tube - a small, flexible tube that keeps the stomach drained of acid and gas bubbles that may build up during surgery.

urinary catheter - a small, flexible tube that allows urine to drain out of the bladder and accurately measures how much urine the body makes, which helps determine how well the heart is functioning. after surgery, the heart will be a little weaker than it was before, and, therefore, the body may start to hold onto fluid, causing swelling and puffiness. diuretics may be given to help the kidneys to remove excess fluid from the body.

chest tube - a drainage tube may be inserted to keep the chest free of blood that would otherwise accumulate after the incision is closed. bleeding may occur for several hours, or even a few days after surgery.

heart monitor - a machine that constantly displays a picture of your child's heart rhythm, and monitors heart rate, arterial blood pressure, and other values.

your child may need other equipment not mentioned here to provide support while in the icu, or afterwards. the hospital staff will explain all of the necessary equipment to you.

your child will be kept as comfortable as possible with several different medications; some which relieve pain, and some which relieve anxiety. the staff will also be asking for your input as to how best to soothe and comfort your child.

TETRALOGY OF FALLOT

after discharged from the icu, your child will recuperate on another hospital unit for a few days before going home. you will learn how to care for your child at home before your child is discharged. your child may need to take medications for a while at home, and these will be explained to you. the staff will give you instructions regarding medications, activity limitations, and follow-up appointments before your child is discharged.

caring for your child at home following tetralogy of fallot repair:

pain medications, such as acetaminophen or ibuprofen, may be recommended to keep your child comfortable at home. your child's physician will discuss pain control before your child is discharged from the hospital.

after surgery, older children usually have a fair tolerance for activity. your child may become tired easily, and sleep more right after surgery, but, within a few weeks, your child should be fully recovered.

long-term outlook after tetralogy of fallot surgical repair:

most children who have had a tetralogy of fallot surgical repair will live healthy lives. activity levels, appetite, and growth will eventually return to normal in most children. your child's cardiologist may recommend that antibiotics be given to prevent bacterial endocarditis after discharge from the hospital.

after initial repair of tetralogy of fallot, pulmonary valve replacement is often indicated in the second or third decade of life to prevent complications such as enlargement of the right ventricle, dysrhythmias, and heart failure. for women wishing to have children, pre-conception evaluation by echocardiogram and/or magnetic resonance imaging (mri) is recommended.

consult your child's physicians regarding the specific outlook for your child.

american heart note on tof tetralogy of fallot (note: before reading the specific defect information and the image associated with it, it

will be helpful to review normal heart function.) what is it? tetralogy of fallot refers to a combination of abnormalities with four key features: 1) a

ventricular septal defect (a hole between the ventricles) and 2) obstruction of blood flow from the right ventricle to the lungs (pulmonary stenosis) are the most important. sometimes the pulmonary valve isn’t just narrowed but is completely obstructed

TETRALOGY OF FALLOT

(pulmonary atresia). also, 3) the aorta (major artery from the heart to the body) lies directly over the ventricular septal defect and 4) the right ventricle develops hypertrophy (thickened muscle).

because of the pulmonary stenosis, blood can’t get to the lungs easily, so the blood doesn’t get as much oxygen as it should. because the aorta overrides the ventricular septal defect, blood from both ventricles (oxygen-rich and oxygen-poor) is pumped into the body. people with unrepaired tetralogy of fallot are often blue (cyanotic) because of the oxygen-poor blood that’s pumped to the body.

what causes it? in most cases, the cause isn’t known although in some patients, genetic factors play a

role. it’s a common type of heart defect. it may be seen more commonly in patients with down syndrome (in association with av canal defects) or digeorge syndrome. some patients can have other heart defects along with tetralogy of fallot.

how does it affect the heart? normally the left side of the heart only pumps blood to the body, and the heart’s right

side only pumps blood to the lungs. in a patient with tetralogy of fallot, blood can travel across the hole (vsd) from the right pumping chamber (right ventricle) to the left pumping chamber (left ventricle) and out into the body artery (aorta). obstruction in the pulmonary valve leading from the right ventricle to the lung artery prevents the normal amount of blood from being pumped to the lungs. sometimes the pulmonary valve is completely obstructed (pulmonary atresia).

how does tetralogy of fallot affect me? most patients are diagnosed with tetralogy of fallot as infants or young children.

patients with unrepaired tetralogy of fallot are usually blue (cyanotic). this is true in infants, children and adults with unrepaired tetralogy of fallot. most adults with tetralogy of fallot have had it repaired in childhood. many people are symptom free but may have residual or recurrent problems. these include valve leakage of blood into the heart’s right side, blockage of blood leaving the heart’s right side and heart rhythm problems. some patients with these problems may have limited exercise tolerance and

TETRALOGY OF FALLOT

may require medicines, repeat operations and/or a special pacemaker to lower the risk of heart rhythm problems.

what can be done about tetralogy of fallot? tetralogy of fallot is treated with two kinds of surgery. one provides temporary

improvement by a shunt to give more blood flow to the lungs. the other is a complete repair of the two most important abnormalities that make up tetralogy of fallot. patients might have one or both surgeries in their lifetime.

shunt operation in some patients, a shunt operation may be done first to

provide more blood flow to the lungs. this is not open-heart surgery and doesn’t fix the inside of the heart. the shunt is usually a small tube of synthetic material sewn between a body artery (or the aorta) and the pulmonary artery. the shunt is removed when a complete intracardiac repair is done later. this is usually done in babies to allow them grow big enough to have a full repair but is occasionally done in adults if a complete repair isn’t an immediate option. some adults had shunts as children, but never got a complete repair. those patients may still be able to get a complete

repair, even as adults. complete repair complete repair tends to be done early in life, but in

some cases it can be done in adulthood. the surgeon closes the ventricular septal defect with a patch and relieves the obstruction to blood flow going to the lungs. this may be done by removing some thickened muscle below the pulmonary valve, repairing or removing the obstructed pulmonary valve and, if needed, enlarging the pulmonary artery branches that go to each lung. sometimes a tube (conduit) with a valve in it is placed between the right ventricle and the pulmonary artery. this is sometimes called a rastelli repair. it’s similar to the type of repair used for some other heart defects.

repeat operations the surgery to open up the pulmonary valve often leads to a leaky pulmonary valve.

although this is better tolerated than the original abnormality, the leaky valve can eventually cause problems. there also can be obstructed pathways that are left behind or develop as the patient grows. both leaky valves and obstructed pathways can cause problems for adult patients with tetralogy of fallot. in many cases, another surgery to replace the pulmonary valve may be needed in adolescence or adulthood.

ongoing care: medical if you’ve had tetralogy of fallot repaired, you’ll need regular follow-up with a

cardiologist who’s had special training in congenital heart defects. you may need to take medicine before or after your operation to help your heart muscle contract or to control heart rhythm abnormalities. your cardiologist will follow your progress with

TETRALOGY OF FALLOT

various tests. these include electrocardiograms, holter monitors, exercise stress tests, echocardiograms and cardiac mris. this will help determine if you need another procedure, such as a cardiac catheterization or more surgery. you should also consult a cardiologist with expertise in caring for adults with congenital heart disease if you’re undergoing any type of non-heart surgery or invasive procedure.

activity restrictions if tetralogy of fallot has been repaired with surgery, and there’s no obstruction or leak

in the pulmonary valve, you may be able to participate in normal activities without much increased risk. you may need to limit your activity if there is leftover obstruction or a pulmonary valve leak, which is common after repair. this limitation may be especially necessary for competitive sports. patients with decreased heart function or rhythm abnormalities may need to limit their activity more. your cardiologist will help decide if you need limits. see the physical activity section for more information.

what will i need in the future? if you’ve had tetralogy of fallot repaired, you’ll need regular lifelong regular follow-up

with a cardiologist who’s had special training in congenital heart defects. some long-term problems can include leftover or worsening obstruction between the

right pumping chamber and the lung arteries. another problem can be a leaky pulmonary valve and enlargement of the heart’s right side. patients with repaired tetralogy of fallot have a higher risk of heart rhythm disturbances called arrhythmias. sometimes these may cause dizziness or fainting.

generally, the long-term outlook is good, but some patients may need medicines, heart catheterization or even more surgery.

endocarditis prevention people with tetralogy of fallot are at increased risk for developing endocarditis. people

with unrepaired and partially repaired tetralogy will need antibiotics to prevent endocarditis before certain dental procedures. if your tetralogy of fallot has been repaired, your cardiologist will let you know if you need to continue to receive these routine antibiotics. see the section on endocarditis for more information.

problems you may have: heart function in the long-term postoperative period, your heart muscle function may decrease and

you’ll need medication. this usually reflects weakening function of the right side of the heart, but in rare instances decreased function of the left ventricle may also occur. medicines that may be needed include diuretics (water pills), drugs to help your heart pump better and drugs to control your blood pressure.

heart rhythm disturbances people with repaired tetralogy of fallot have a higher risk of heart rhythm disturbances

called arrhythmias. these can originate from the atria or the ventricles. sometimes they may cause dizziness or fainting. you may need medicine to control them. sometimes patients also need blood thinners to reduce the risk of stroke related to the arrhythmias. in rare cases, you may need a procedure in the cardiac catheterization laboratory or the operating room to eliminate these arrhythmias and control symptoms. see the arrhythmias section for more information. some patients need pacemakers or implantable defibrillators to treat their arrhythmias.

pregnancy

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in many cases, women with repaired tetralogy of fallot have successful, full-term pregnancies. some woman with significant residual heart problems may be at risk for a difficult pregnancy. see the section on pregnancy for more information. once tetralogy of fallot has been repaired, the pregnancy risk is low unless the woman has some side effects or residual effect like irregular heart rhythms or persistent narrowing of the pulmonary valve. any woman considering pregnancy should have a complete physical examination by her cardiologist in consultation with a multi-disciplinary team before becoming pregnant to find out what, if any risk there might be with the pregnancy. pregnancy is considered to be high-risk and not recommended for women with unoperated tetralogy of fallot who remain “cyanotic” (blue).

will i need more surgery? after the first complete repair, residual problems may require you to have more open-

heart surgeries or procedures in the cardiac catheterization laboratory. in some cases, a procedure done in the cardiac catheterization laboratory using a balloon-tipped catheter to dilate and/or place an expandable stent in narrowed areas may be needed.