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There are two types of heart disease in children
- Congenital and Acquired. Congenital heart disease
(als known as a Congenital Heart Defect) is present
at birth. Some of the defects in this category are patent
ductus arteriosus, (PDA) Atrial Septal defects, (ASD)
and Ventricular Septal Defects (VSD). These defects
(ASD and PDA) have been found to be more common
amongst females. Earlier these defects needed complicated
surgical procedures, but not anymore. Advancements in
medical technology have ensured a smoother, non-surgical,
minimally invasive procedure of closing these heart
defects through a very small incision in the groin,
performed under x-ray guidance in the cardiac catheterization
laboratory instead of the operation theatre. This non-surgical
method has success rates (almost 95 per cent) comparable
to surgery, albeit without the trauma and risks associated
with open-heart surgery.
Benefits to
patient include:
1) Less time
spent in the hospital,
2) Quicker
recovery time,
3) Reduced
post-procedure pain and
4) Avoiding a
scar on the chest.
Research for
these methods had started in the ’70s and was attempted sporadically in the ’80s
but it’s only in the last five years that they have almost been
perfected.
Let’s take a
look at what these heart defects in children are and how they are rectified.
ATRIAL SEPTAL DEFECT (ASD)
Atrial septal
defect (ASD) is when there is a communication or hole between the left and right
atrium (the right and left side of the upper chambers of the heart), which
causes an increase in blood flow in the right side of the heart and to the
lungs. Because it is receiving so much extra blood, the right side of the heart
does more than its normal share of work. The heart can dilate, the muscle can
become weak, and the pressures in the pulmonary arteries, supplying blood to
lung, can increase (pulmonary hypertension) due to the increase in blood flow.
If the defect closes on its own or with the aid of surgery, these consequences
can be avoided.
Thus, the
patient may feel tired, have difficulty breathing, and fail to grow normally, or
be sick more often with respiratory infections such as colds or pneumonia.
Larger ASDs can lead to heart failure and death. The unusual part about ASDs is
that the symptoms rarely appear in newborns and infants and they are typically
discovered at preschool routine examination when the doctor hears a "murmur" and
investigates it. Sometimes ASDs go undetected and manifest themselves only when
the patient is in his 20s or even 30s. To close this hole, the interventional
cardiologist will insert a tube that carries the closing device through a blood
vessel in the groin. The closing device could be an umbrella or a
patch.
Once the tube
passes through the hole and gets to the other side, the closing device is lodged
on the hole and once it’s certain that the hole has been covered correctly, the
tube is withdrawn. A Transesophageal Echocardiography (TEE) monitors the entire
procedure. The colour visuals allow the cardiologist to be sure that the entire
procedure has been done correctly, before letting the umbrella stay put on the
hole. With most of the presently used umbrella devices, half of the device is
connected to one side of the atrial septum, and the second half of the device
attached to the other portion, forming a sort of "sandwich" of the defect. The
device is held in place by the natural pressures generated within the atria.
Defects amenable
to such device therapy tend to be smaller (less than 20 to 25 mm [3/4 to 1 inch]
diameter). Importantly, these lesions must be centrally located within the
atrial septum. Defects at the very upper or lower edges of the atrial septum
(called ostium primum or sinus venosus) are not good candidates for this
procedure, because these defects usually involve other abnormalities of the
heart valves, or venous drainage from the lungs. The patient’s primary
cardiologist can make this determination.
VENTRICULAR
SPETAL DEFECTS (VSD)
The other defect
is the Ventricular Septal Defect (VSD). In a case of VSD, there is a defect
(hole) in the wall (septum) between the two lower chambers (ventricles) of the
heart. VSDs are the most common type of heart defect. As in the case of the ASD,
the heart can dilate, the muscle can become weak, and the pressures in the
pulmonary arteries can increase (pulmonary hypertension) due to an increase in
blood flow. Like ASDs, the size and therefore, the clinical course of these
defects is quite variable. Some remain large, while others become smaller over
time. It is not unusual for small-to-medium sized VSDs to eventually close
spontaneously. Many, but not all that remain will require closure by the
surgeon.
The VSD can
cause symptoms such as growth failure, fatigue, difficult or rapid breathing or
chronic respiratory infections. These kinds of defects are more difficult to
close than the ASDs, especially if the holes are closer to the valves. If they
are away from the valves, the same method by which the ASDs are treated can be
applied. Our body’s regenerative system is so strong that within six weeks or so
of the operation, tissue will grow over the device that covers the hole and that
device functions in harmony with the body.
PATENT DUCTUS
ARTERIOSUS (PDA)
Patent Ductus
Arteriosus (PDA) is a heart defect that occurs when a blood vessel called the
ductus arteriosus, which is normal while the baby is in the womb, fails to close
after the baby is born. The ductus arteriosus should close permanently in most
cases within 24 hours. This condition can cause symptoms such as fatigue,
difficult or rapid breathing, or chronic respiratory infections. A patient with
a PDA can also be asymptomatic (without symptoms). Large openings can lead to
heart failure and death. Cardiologists close these defects with devices that
look like springs or coils or even plugs. The larger holes can only be covered
with the plugs, which are more expensive albeit more reliable. For all these
procedures to be successful, the sizing of the hole has to be accurate.
Generally, an inflated rubber balloon is passed through the hole and then pulled
through. This allows the cardiologist to note the ‘stretched diameter’ of the
hole
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