2. Excluding biscuspid aortic valves, ventricular septal
defects (VSDs) are the most common congenital
cardiac lesion, occurring in isolation or in association
with other congenital cardiac defects.
The ventricular septum is divided into four
components, the trabecular or muscular septum
extending to the apex, the inlet (posterior) septum
between the atrioventricular valves, the outlet septum
which subtends the great arteries and the membranous
septum which lies under the aortic root. Defects can
arise in any position but the membraneous septum is
most commonly affected.
3. The ventricular septum forms the medial wall and
normally bulges in to the right ventricle. It is almost
muscular except for the superiorly located
membraneous septum just below the right and
posterior (noncoronary) cusps of te aortic valve. On the
left ventricular side the demarcation between the
membraneous septum and the muscular septum is
called limbus marginalis.
The membranous septum is both interventricular and
atrioventricular. The former portion lies between the
left ventricle and the right ventricle. The latter,
superior, part of the membraneous septum lies
between the left atrium and the right atrium.
5. A ventricular septal defect is an opening in the
interventricular septum that permits
communication between the two ventricles.
or
A VSD is an opening or hole (defect) in the wall
(septum) between the heart’s two pumping
chambers (ventricles).
7. Before a baby is born, the right and left ventricles of its heart are
not separate. As the fetus grows, a wall forms to separate these two
ventricles. If the wall does not completely form, a hole remains.
This hole is known as a ventricular septal defect, or a VSD.
Ventricular septal defect is one of the most common congenital
heart defects. The baby may have no symptoms, and the hole can
eventually close as the wall continues to grow after birth. If the
hole is large, too much blood will be pumped to the lungs, leading
to heart failure.
The cause of VSD is not yet known. This defect often occurs along
with other congenital heart defects.
In adults, ventricular septal defects are a rare but serious
complication of heart attacks. These holes do not result from a birth
defect.
9. Defects of the ventricular septum, which may be large in relation to the
size of the heart at birth, tend to become smaller or to close in early
childhood. If closure is insufficient to prevent a large shunt, the small
pulmonary vessels may be damaged by being exposed to the ejectile
force and pressure of left ventricular contraction. Irreversible
pulmonary hypertension may be produced.
The effect of a ventricular septal defect (VSD) depends upon its size
and upon the impedance to blood flow imposed by the pulmonary
arterial vessels.
If the defect is small, the jet of blood from the high pressure left
ventricle to the low-pressure right ventricle has little hemodynamic
effect.
If the defect is large and the impedance of the pulmonary vessels low, a
large shunt develops and the pulmonary blood flow becomes
substantially more than systemic. If , on the other hand, there is a high
pulmonary vascular resistance, the pulmonary blood flow is little or no
more than the systemic and the pressure in both circuits is similar. If the
pulmonary vascular resistance is very high, the shunt reverses (the so
called Eisenmenger Complex).
11. Symptoms
In VSD the patient with a small defect, there are no symptoms,
but there is a loud ‘tearing’ pansystolic murmur often
accompanied by a thrill, maximal to the left side of the lower
sternum.
Newborn infants have a high pulmonary vascular resistance
which falls to normal levels in the first 3 months of life. At this
point, a large defect at ventricular level is liable to produced
cardiac failure and require treatment.
12. Signs
Cardiac failure is usually obvious in the infant or
small child with a significant left to right shunt
through a large VSD.
In the presence of a large left to right shunt the
pulse is usually small and the venous pressure
normal, unless there is right heart failure.
Both left and right ventricles may be
hyperdynamic and with a large shunt, a soft
pansystolic murmur is heard at the lower sternal
edge, usually accompanied by a mid-diastolic
murmur at the apex due to high flow through the
mitral valve,
13. Although there are some patients in whom large
defects get smaller and become restrictive to flow,
most, if untreated will ultimately progress to
irreversible pulmonary hypertension as a result of
pulmonary vascular disease.
The development of pulmonary vascular disease is
often heralded by an improvement in the
symptoms of cardiac failure as the resistance to
follow through the lungs decreases flow.
Right ventricular hypertrophy is evident, the
pulmonary second sound may be accentuated and
followed by the early diastolic murmur of
pulmonary regurgitation.
14. HISTORY-
Infants with larger defects develop heart failure, usually by 3 months
of age. Parents may note tachypnea, fatigue with feedings, poor
weight gain and excessive sweating. Infants and children with small
ventricular defects are asymptomatic; their defects are ordinarily
detected early by routine examination because of the loudness of the
murmur.
PHYSICAL EXAMINATION-
Typical loud, harsh holosystolic murmur
Middiastole rumble
Pulmonary rales and peripheral edema
The second heart sound is loud and single
cyanosis
CHEST X-RAY
It is normal with a small defect, but with a large left to right shunt
there is some enlargement of the heart and, more specifically ,
prominence of the pulmonary vessels, left atrium and both ventricles.
15. ECG
The ECG in small defects is normal. When the left to right shunt is large, there
is usually evidence of biventricular enlargement, manifested by abnormally
deep but narrow Q waves and tall R waves in the left chest leads. In cases
with pulmonary vascular disease, the ECG pattern of isolated right ventricular
hypertrophy develops. Large defects may involve the conducting tissue and
left axis deviation occurs.
ECHOCARDIOGRAPHY
Two-dimensional echocardiography, along with Doppler echocardiography
and colour flow imaging can assess the size and location of virtually all
ventricular septal defects (VSDs). Doppler echocardiography also provides
physiological information including right ventricular pressure, pulmonary
artery pressure and the difference in pressure between the ventricles.
Measurement of left atrial and left ventricular diameter provides semi-
quantitative information about shunt volume.
CARDIAC CATHETERIZATION
There is a step-up in oxygen saturation at the right ventricular level. The
degree of pulmonary hypertension can be measured, and pulmonary vascular
resistance should be calculated. Selective biplane cineangiography in the left
ventricle will outline the defect.
1. Establish diagnosis
2. Determine type and severity
3. Confirm and exclude associated lesions
16. Medications
With a small lesion the prognosis is excellent and no intervention
is required beyond antibiotic prophylaxis where indicated.
In moderate size lesions a trial of furosemide, angiotensin-
converting enzyme (ACE) inhibitor and digoxin may work.
Large lesions with a big shunt usually require medical
management for heart failure with diuretics ± ACE inhibitors.
Otherwise surgical closure is required before vascular disease
compromises the surgical outcome – usually within the first 6-12
months of life
Surgical repair is required if:
There is uncontrolled heart failure, including poor growth. Even very
small babies may be considered.
If the pulmonary artery pressure is raised then repair may be considered
before the first birthday.
Even with normal pulmonary artery pressure, if the ratio of aortic flow:
pulmonary flow exceeds 2:1, then repair is required.
17. Palliative:
Pulmonary artery banding (placing a band around
the main pulmonary artery to decease pulmonary
blood flow) in infants in severe CHF. It is unusual
because of the improvement of the surgical
techniques.
Complete repair(procedure of choice):
Small defects are repaired with a purse-string
approach.
Large defects usually require a knitted Dacron
patch sewn over the opening. Both procedures are
performed via cardiopulmonary bypass. The
repair is generally approached through the right
atrium and the tricuspid valve.
18. Except for VSD that is caused by a heart attack,
this condition is always present at birth.
Drinking alcohol and using the antiseizure
medicines depakote and dilantin during
pregnancy may increase the risk of VSDs.
Other than avoiding these things during
pregnancy, there is no known way to prevent a
VSD.
19. Aortic insufficiency (leaking of the valve that separates the left ventricle
from the aorta)
Damage to the electrical conduction system of the heart during surgery
(causing an irregular heart rhythm)
Delayed growth and development (failure to thrive in infancy)
Heart failure
Infective endocarditis (bacterial infection of the heart)
Pulmonary hypertension (high blood pressure in the lungs) leading to
failure of the right side of the heart
Postoperative problems can occur:
A small residual ventricular septal defect (VSD) (not uncommon).
Depending upon heart size, symptoms and degree of shunting it may be
necessary to re-operate.
Right bundle branch block may be caused by operative trauma, and
occasionally complete heart block can occur. This has a late mortality.
Ventricular dysfunction and ventricular arrhythmia can be a problem.
20. Nursing diagnosis
Cough related to lung congestion secondary to the
effect of general anesthesia
Goal
Reduce the coughing of the patient
Interventions
Assess the patient for coughing
Auscultate chest of the patient with pediatric
stethoscope
Give chest physiotherapy.
Give nebulisation with Levolin as dose of ¼ resp.
Auscultate . after giving nebulization
Expected outcomes
Coughing will be reduced.
21. Nursing diagnosis
High risk for fall related to the age and weakness
of the child
Goal
Reduce the chances of fall
Interventions
Assess the chances of getting fall.
Provide side rails to prevent fall.
Provide calling bell for the patient.
Allow the mother to stay with the patient.
Do close observation of the patient.
Expected outcomes
No fall of the patient will be there.
22. Nursing diagnosis
Pain related to the surgical wound as evidenced by
facial pain scale
Goal
Reduce pain
Interventions
Assess the location & source of pain.
Assess the severity of pain.
Assess the patient from facial expression as per
pediatric pain scale.
Provide comfortable position.
Administer oral analgesics (Syrup Ibugesic plus)
2.5ml as ordered by physician.
Expected outcomes
Pain will be reduced.
23. Nursing diagnosis
High risk for infection related to the presence of
surgical wound
Goal
Reduce risk of getting infection.
Interventions
Assess patient for signs of infection.
Maintain aseptic technique during any procedure.
Do hand washing before and after each procedure,
touching patient.
Check temperature every 4 hourly and SOS.
Administer prescribed antibiotics (Syrup Augmentin
Duo) 2.5ml as prescribed by physician.
Check vital signs and record it.
Expected outcomes
No infection will be present.
24. Nursing diagnosis
Knowledge deficit of parents of the child related to
the disease process as evidenced by frequent
questioning
Goal
Increase knowledge level of the parents.
Interventions
Assess the knowledge level of the parents of the
patient.
Provide information about disease process of the
patient.
Clear doubts of the parents.
Explain about medicines, diet, comfort and sleep,
wound care and follow up care.
Take feedback from the parents.
Expected outcomes
Knowledge level of the parents will be increased.
25. Nursing diagnosis
Anxiety of parents related to the disease process,
treatment regimen, hospital stay as evidenced by
facial expression and verbalization
Goal
Reduce anxiety of the parents.
Interventions
Assess the anxiety level of the parents.
Provide information about disease process,
treatment regimen, and hospital stay.
Give psychological support to the parents.
Counsel the parents if needed.
Expected outcomes
Anxiety of the parents will be reduced.
26. Fortunately most ventricular septal defects are
small. Many become smaller close spontaneously
during childhood. Among patients with large
defects congestive heart failure is likely in infancy
and causes death unless managed appropriately.