Heart,
section
through
the
middle
Tetralogy
of
Fallot
Cyanotic
´Tet
spell´
Definition:
A type of heart defect present at birth (congenital) consisting of four different abnormalities. It usually results in insufficiently oxygenated blood being pumped to the body causing cyanosis (bluish discoloration of the skin).
Alternative
Names:
TET; TOF
Causes
And
Risk:
The
cause
of
most
congenital
heart
defects
is
unknown.
Multiple
factors
seem
to
be
involved.
Prenatal
factors
associated
with
higher
than
normal
risk
for
this
condition
include
maternal
rubella
or
other
viral
illnesses
during
pregnancy,
poor
prenatal
nutrition,
maternal
alcoholism,
mother
over
40
years
old,
and
diabetes.
There is a higher incidence of tetralogy of Fallot in children with Down syndrome (a common genetic disorder which results from having an extra 21st chromosome).
Tetralogy of Fallot is classified as a cyanotic heart defect because the condition causes insufficiently oxygenated blood to be pumped to the body, which leads to cyanosis (a bluish-purple coloration to the skin) and shortness of breath.
The classic form of Tetralogy includes 4 defects within the heart structures:
Ventricular
septal
defect
(hole
between
the
right
and
left
ventricles)
Narrowing
of
the
pulmonic
outflow
tract
(tube
that
connects
the
heart
with
the
lungs)
An
aorta
(tube
that
carries
oxygenated
blood
to
the
body)
that
arises
from
both
ventricles,
rather
than
exclusively
from
the
left
ventricle
A
thickened
muscular
wall
of
the
right
ventricle
(right
ventricular
hypertrophy)
There
is
flow
of
deoxygenated
(blue)
blood
into
the
general
body
circulation
and
decreased
blood
flow
to
the
lungs.
At birth, infants may not show the signs of the cyanosis, but later may develop sudden frightening episodes of bluish skin from crying or feeding (called "Tet spells"). Tetralogy of Fallot occurs in approximately 5 out of 10,000 infants.
Prevention:
There is no known prevention.
Symptoms:
Difficult
feeding
(poor
feeding
habits)
Failure
to
gain
weight
Poor
development
Cyanosis
which
becomes
more
pronounced
during
periods
of
agitation
Passing
out
Sudden
death
Clubbing
of
fingers
(skin
or
bone
enlargement
around
the
finger
nails)
Shortness
of
breathaggravated
byexercise
Squatting
during
episodes
of
cyanosis
Signs And Tests:
A
physical
examination
with
a
stethoscope
almost
always
reveals
a
heart
murmur.
Tests:
EKG
(elctrocardiogram)
showing
the
thickening
of
the
right
ventricle
muscle
CBC
showing
increased
red
blood
cells
Chest
X-ray
showing
a
"boot
shaped"
heart
and
dark
lungs
Cardiac
catheterization
Echocardiogram
for
the
definitive
diagnosis
Treatment:
Surgery
to
repair
the
defects
in
the
heart
is
always
performed
relatively
early
in
life.
Sometimes
a
preliminary
surgery
to
create
increased
blood
flow
to
the
lungs
is
done
before
definitive
corrective
surgery.
Corrective
surgery
widens
the
narrowed
pulmonary
valve,
and
the
ventricular
septal
defect
is
closed.
Parents of children with tetralogy of Fallot can be assisted in coping with the symptoms of the disease. Some interventions to consider include:
If
a
child
does
become
blue,
the
parent
should
immediately
place
the
child
on
his/her
side
and
put
the
knees
up
to
the
chest,
calm
the
baby
and
seek
medical
attention
Feeding
the
child
slowly
Giving
smaller,
more
frequent
meals
Decreasing
the
child´s
anxiety
by
remaining
calm
Minimizing
crying
by
trying
to
anticipate
the
child´s
needs
Recruiting
others
to
care
for
the
child
to
prevent
parental
exhaustion
and
burn-out
Prognosis:
Most cases can be surgically corrected. Prognosis (probable outcome) with surgery is good. Without surgery, death usually occurs around 20 years old.
Complications:
Delayed
growth
and
development
Seizures
during
periods
of
insufficient
oxygen