Identifying the problem of congenital heart disease

Identifying the problem of congenital heart disease

Heart disease is not only a condition of the aged -- children
can also have congenital or acquired heart disease. The Jakarta
Post's regular contributor on pediatrics Dr. Donya Betancourt
discusses the different types of congenital heart disease in the
second article of a three-part series.

JAKARTA (JP): Holes in the heart, obstructed blood flow and
abnormal blood vessels are the three main types of congenital
heart defects, meaning that children are born with them.

A hole in the heart happens in the septum (wall) of the heart
chambers or between major blood vessels allowing the heart to mix
oxygenated and nonoxygenated blood. The three most common defects
are VSD, ASD and PDA.

VSD (ventricular septal defect), which is a hole in the wall
between the right and the left ventricle causing blood to move
from the left ventricle to the right ventricle because the left
ventricle by nature has higher pumping pressure. This defect
causes the right side of the heart to work harder as it is
overloaded and also causes extra blood to be sent to the lungs
which causes high blood pressure and lung congestion. A small
VSD may close on it's own without treatment but larger ones may
need surgical correction.

ASD (atrial septal defect) is the hole between the right and
left atrium which also allows blood to move from the left atrium
to the right atrium and it is similar to VSD in that it moves
extra blood to the lungs but typically on a more mild basis. In
PDA (patent ductus arteriosus, and patent means persistent), the
fetus has an opening passage between the pulmonary artery and
aorta that allows blood in the fetus to bypass the lungs.

Once the baby is delivered and starts breathing oxygen on
his/her own, the pressure in the lungs increases and it closes
this opening. In most cases this closure will occur in a few
hours after birth but if it does not, oxygen-rich blood will be
directed back to the lungs and can cause heart failure in the
newborn. Surgery was once required for closing a patent duct but
today we have medication that stimulate the ducts to close and
surgery is left for the cases where medication fails.

The symptoms in these three groups are similar. Usually, the
lungs overload, the degree of overload varies depending on the
size of the defect. Typically there are no outward symptoms --
usually the defect is only found by detecting a heart murmur or
the child gets tired when feeding and/or sweats profusely.
Failure to grow or difficulty in breathing from lung congestion
are also good indicators of possible heart problems.

Obstructed blood flow: This condition occurs from blood
vessels or valves becoming obstructed or narrowed, resulting in
the heart working harder to move blood.

Three common defects are pulmonary stenosis, aortic stenosis
and coarctation of aorta. In pulmonary stenosis, the group of
patients will typically have blue skin, pulmonary stenosis is the
narrowing of the pulmonary valve which is the opening to the
right ventricle to the pulmonary vessel, resulting in the muscle
of the right ventricle thickening from working harder to send
blood through the smaller opening, and causing an inadequate
blood supply to the lungs resulting in an inadequate supply of
oxygen to the body tissue, causing cyanosis (blue skin).

Aortic stenosis is a narrowing of the aortic valve, the
opening of the left ventricle to the aorta. The heart muscle
thickens and the ventricle enlarges, the symptoms may vary from
no symptom to chest pain during or following vigorous exercise.

Coarctation of aorta is a narrowing of the aorta so it
restricts blood flow to the lower part of the body and it causes
high blood pressure in the upper part of the body, which is
sometimes not diagnosed until later childhood or adulthood. The
symptoms of these aortic problem will be a pressure effect; the
heart works harder and ventricle gets enlarged also the
obstruction results in a back up of blood in the lungs and causes
lung congestion with shortness of breath, an inability to eat and
no weight gain.

Abnormal blood vessels: This condition mostly involves
incorrectly formed or positioned blood vessels going to and from
the heart, such as TGA (transposition of the great vessels) and
TOF (tetralogy of fallot).

TGA happens when the pulmonary artery leaves the left
ventricle and the aorta leaves the right ventricle, resulting in
oxygen-rich blood being carried to the lungs instead of the body
and oxygen-poor blood being carried to the body. This is a
serious and immediately life-threatening defect but most newborns
with this defect will also have the opening between the wall of
the left and the right sides of the heart allowing the blood to
mix but the child will have cyanosis (blue skin) and need
corrective surgical treatment.

TOF is found in 10 percent of all congenital heart diseases.
There are a combination of 4 defects: a hole in the ventricular
septum, a narrowing passage between the right ventricle and
pulmonary artery, a shift in the connection of the aorta to the
heart and thickened muscle in the right ventricle. This condition
results in blue skin because the oxygen-poor blood flows from the
right side to the left and out to the body. This condition
requires surgical correction.

The third and final part next week will focus on looking for
signs of a heart problem in children. Questions? Contact Dr.
Donya at drdonya@hotmail.com, or you can reach her at
features@thejakartapost.com.