2. INTRODUCTION
Tetralogy of Fallot refers to a type of congenital heart
defect. Congenital means present at birth. Tetralogy of
Fallot (TOF or "TET") is a complex condition involving
several associated congenital heart defects that occur
due to abnormal development of the fetal heart.
4. DEFINITION :
Tetralogy 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 involves four heart defects:
A large ventricular septal defect (VSD)
Pulmonary stenosis
Right ventricular hypertrophy
An overriding aorta or dextraposition of aorta
5.
6.
7. EPIDEMIOLOGY :
Tetralogy of Fallot occurs in approximately 400 per
million live births.
Tetralogy of Fallot is a rare, complex heart defect that
occurs in about 5 out of every 10,000 babies.
Occurs equally in girls and boys.
9. A hole between the two bottom chambers (ventricles)
of the heart. The defect is centered around the most
superior aspect of the ventricular septum (the outlet
septum), and in the majority of cases is single and
large. In some cases thickening of the septum (septal
hypertrophy) can narrow the margins of the defect.
11. A narrowing of the right ventricular outflow tract and
can occur at the pulmonary valve (valvular stenosis) or
just below the pulmonary valve (infundibular stenosis).
Infundibular pulmonic stenosis is mostly caused by
overgrowth of the heart muscle wall (hypertrophy of the
septoparietal trabeculae), however the events leading to
the formation of the overriding aorta are also believed to
be a cause. The pulmonic stenosis is the major cause of
the malformations, with the other associated
malformations acting as compensatory mechanisms to
the pulmonic stenosis. The degree of stenosis varies
between individuals with TOF, and is the primary
determinant of symptoms and severity. This
malformation is infrequently described as sub-
pulmonary stenosis or subpulmonary obstruction
13. The right ventricle is more muscular than normal,
causing a characteristic boot-shaped appearance as
seen by chest X-ray. Due to the misarrangement of the
external ventricular septum, the right ventricular wall
increases in size to deal with the increased obstruction
to the right outflow tract. This feature is now generally
agreed to be a secondary anomaly, as the level of
hypertrophy
15. An aortic valve with biventricular connection, that is,
it is situated above the ventricular septal defect and
connected to both the right and the left ventricle. The
degree to which the aorta is attached to the right
ventricle is referred to as its degree of "override." The
aortic root can be displaced toward the front
(anteriorly) or directly above the septal defect, but it is
always abnormally located to the right of the root of
the pulmonary artery. The degree of override is quite
variable, with 5-95% of the valve being connected to
the right ventricle.
16. CAUSES :
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:
Poor nutrition
Overuse of alcohol
Age (being older than 40)
Diabetes
Genetic factors : chromosome 22 deletions and
DiGeorge syndrome, Down syndrome
Heredity
17. SIGNS AND SYMPTOMS :
CYANOSIS
TET SPELLS
HEART MURMUR
FAILURE TO GAIN WEIGHT
CLUBBING
18. DIAGNOSTIC TESTS
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 :
The heart defect usually occur during the first weeks of
life. Your infant's doctor may notice signs or symptoms
during a routine check-up. Some parents also notice
cyanosis (a bluish tint to the skin, lips, and fingernails)
or poor feeding and bring the baby to the doctor.
19. Physical Exam
During a physical exam, the doctor may:
A physical examination with a stethoscope almost
always reveals a heart murmur.
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
22. SURGICAL TREATMENT
A) COMPLETE INTRACARDIAC REPAIR :
The first total repair of Tetralogy of Fallot was done by a
team led by C. Walton Lillehei at the University of
Minnesota in 1954 on a 11-year-old boy. Total repair on
infants has had success from 1981, with research indicating
that it has a comparatively low mortality rate.
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.
23. 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.
25. NURSING MANAGEMENT
Feeding and Nutrition :
Small, frequent meals may be easier for your baby to
handle. 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.
26. Activity Restrictions
Child needs to restrict activity or exercise
Child can play in organized sports, especially contact
sports club.
You need a note for child’s school or coaches about
limiting your child's exercise
27. Nursing diagnosis
Impaired gas exchange r/t disturbed pulmonary blood flow
Decreased cardiac output r/t reduce myocardial function
Activity intolerance r/t hypoxia
Imbalance nutrition less than body requirement r/t
excessive energy demand required by increased cardiac
workload
Parental anxiety/fear r/t life threatening illness
Ineffective family coping r/t crisis situation and fear of
losing child
Knowledge deficit r/t long term problem & prevention of
complications
Risk for infection r/t chronic illness