2. Objectives:
At the end of 2 hours of active learning discussion, the
students will be able to:
1. Define acyanotic heart defects
2. Understand atrial septal defect and ventricular septal
defect in terms of:
a. anatomical defect
b. clinical manifestations
c. diagnostics
3. Formulate nursing diagnoses and appropriate nursing
care
3. Definition:
Acyanotic Heart Defects – a
congenital disorder manifested
with left to right shunting and
obstructive lesions. Clinical
signs are not always apparent
at birth, they manifest anytime
during
infancy
or
early
childhood.
4. Defects:
a. Left to right shunting lesions, increased pulmonary
blood flow
• The blood is shunted through an abnormal opening
from the left side of the heart to the right side of the
heart
• Pulmonary blood flow increases because of the extra
volume in the right side. There is a “step-up” 02
saturation in the right side of the heart (abnormal
increased) because of the addition of more highly
saturated blood. Physiologic effects include increased
pulmonary blood flow, increased cardiac workload
(including ventricular strain, dilation, and hypertrophy).
ď‚— Examples: Atrial Septal Defect (ASD), Ventricular Septal
Defect (VSD), Patent Ductus Arteriosus (PDA), and
Atrioventricular Septal Defect (AVSD).
5. b. Obstructive or stenotic lesions – stenosis of an
opening can occur in a valve or vessel constricting or
obstructing blood flow through the area. Pressure rises
in the area behind the obstruction; blood flow distal to
the obstruction may be decreased or absent.
Physiologic effects of obstructive or stenotic lesions
include increased cardiac workload and ventricular
strain, clinical consequence of CHF, decreased CO
and pump failure.
Example: Pulmonary stenosis, aortic stenosis, Coarctation
of Aorta, and interrupted aortic archs.
6. Atrial Septal Defect (ASD)
Incidence and Pathophysiology:
â—Ź ASD accounts for approximately 10% of all CHDs. It is seen
more frequently in females than males.
â—Ź The lesion consists of an abnormal opening between the
atria
Types of Lesions:
1. Ostium Secundum – located at the middle of the atrial
septum (fossa ovalis), the most common type.
2. Ostium Primum – located low in the atrial septum, results
from a defect in endocardial tissue formation and is often
associated with a left mitral valve malformation.
3. Sinus Venosus – which is located high in the septum close
to the SVC
8. Atrial Septal Defect (ASD)
Altered Hemodynamics:
â—Ź Lower right ventricular compliance which is the ease of
ventricular diastolic filling, compared with left ventricular
compliance leads to left to right shunting at the atrial level
through the ASD. This increased blood flow through the
ASD leads to an enlarge RA and RV and increased
pulmonary blood flow.
9. Manifestations:
â—Ź Most infants and children are asymptomatic but over years to decades
may experience:
1. Fatigue and SOB
2. Palpitations or atrial dysrythmias – result of atrial enlargement
3. Recurrent respiratory infections can occur when there is a large amount
of pulmonary blood flow
4. Systolic murmur is produced by increased blood flow across the
pulmonary valve.
5. Diastolic murmur is present with large shunts
6. Stroke or major organ damage can occur because of embolization of
thrombus, air or other materials – PARADOXIMAL EMBOLISM
11. Atrial Septal Defect
Therapeutic Management:
1. Asymptomatic child is followed by cardiologist. Spontaneous closure can
occur in the first years of life for smaller size secundum ASDs.
2. Elective surgical repair is performed around 2-5 years of age
3. Surgical repair is recommended for all sinus venosus and ostium primum
defects.
Medical Management:
1. Asymptomatic patients with moderate size secundum ASDs are
monitored for spontaneous closure in the first years of life with
medication.
2. Symptomatic infants and children are treated with diuretics and digoxin
as indicated
3. Atrial dysrythmias are treated with appropriate antidysrythmics
Surgical Management:
â—Ź Surgical closure using either sutures or a pericardial prosthetic patch is
performed on an elective basis early in childhood. This is an open heart
procedure, through a sternal incision.
â—Ź Mortality rate is <2%, with most centers near 0%. For the young adult with
ventricular dysfunction or pulmonary, the risk can be significantly higher.
â—Ź Complications include sinus node and atrial dysrythmias
12. Ventricular Septal Defect (VSD)
Incidence and Pathophysiology:
â—Ź VSDs account for approximately 25% of all CHDs.
â—Ź VSD is the most common congenital cardiac lesion and is
often accompanied by other cardiac defects.
â—Ź The lesion consists of an abnormal opening between the
right and left ventricles which may vary in size from a
miniscule hole to complete absence of the septum, resulting
in a common ventricle.
13. Ventricular Septal Defect (VSD)
Altered Hemodynamics:
â—Ź The degree of left to right shunting through the VSD
depends on the size of the defect and the pulmonary
vascular resistance compared with the systemic vascular
resistance. The pulmonary vascular system is high in the
newborn. Over the first few weeks of life, the resistance
decreases. As this occurs, an increased amount of blood
shunts left to right of the VSD level. The pulmonary
vascular circulation receives increased pulmonary blood
flow. With large defects the pulmonary arteries are
exposed to systemic pressures, causing pulmonary
hypertension, and over time, progressive pulmonary
vascular disease.
15. Ventricular Septal Defect (VSD)
ď‚— Manifestations:
â—Ź Signs and symptoms vary with the size of the defect and
the presence of associated cardiac lesions. Clinical
symptoms are usually not seen at birth because of
continued high pulmonary vascular resistance in the
newborn. Infants with moderate to large defects will
become symptomatic within the first few weeks of life.
â—Ź Children with small defects will remain asymptomatic.
18. Diagnostics:
• Chest x-ray -- looks to see if there is a large heart with
fluid in the lungs
• ECG -- shows signs of an enlarged left ventricle
• Echocardiogram -- used to make a definite diagnosis
• Cardiac catheterization (rarely needed, unless there are
concerns of high blood pressure in the lungs, in which
case surgery to close the defect is generally not
recommended)
• MRI of the heart -- used to find out how much blood is
getting to the lungs
19. Ventricular Septal Defect (VSD)
ď‚— Therapeutic Management:
â—Ź From 20%-80% of all VSDs closed spontaneously.
1. Many small lesions do not require surgical intervention.
2. If there is aortic valve regurgitation related to VSD position near the
valve and even if the defect is small, surgery is indicated to reduce
the progression of valve insufficiency.
3. Antibiotic prophylaxis is indicated for all VSDs.
ď‚— Medical Management:
1. Infants who develop CHF- digoxin diuretics, ACE inhibitors to
reduce afterload.
2. Nutritional supplements are added to infant formula to increase
caloric intake.NGT feeding or gastrostomy tube feeding for infants
who are unable to obtain adequate calories orally
3. Avoid exposure to respiratory infections.
20. Ventricular Septal Defect (VSD)
ď‚— Surgical Management:
1. Pulmonary artery banding for children with multiple muscular
VSDs. In this palliative procedure, a band is placed around
the main pulmonary artery, decreasing blood flow, reducing
the severity of CHF and decreasing the risk of pulmonary
vascular disease.
â—Ź The current trend is to perform corrective surgery earlier in
life, and consequently, pulmonary artery banding is
performed less frequently than in the past.
3. Total correction is accomplished by placing sutures to close
small defects or by placing a pericardial or prosthetic patch
over moderate to large defects.
21. â—Ź The surgical approach is usually through the RA to avoid a
right ventricular incision which could impair the contractility
of the ventricle.
â—Ź VSDs just below the pulmonary valve are closed through
an incision in the main pulmonary artery. Mortality is 5%8%, depending on the age and type of VSD.
â—Ź Complications include residual VSDs, pulmonary
hypertension in the postoperative period, heart block that
may require a pacemaker and an abnormal rhythm called
junctional ectopic tachycardia.
â—ŹCO can be significantly decreased if dysrythmias are
persistent. Post pericardiotomy syndrome can also occur.
22. Nursing Diagnosis and Care of the
Child with Left-to-Right Shunting
(Acyanotic)
Impaired gas exchange
• Monitor intake and output
• Limit fluids as ordered
• Administer diuretics as ordered
• Position changes every 2 hours or as
ordered
23. Nursing Diagnosis and Care of the
Child with Left-to-Right Shunting
(Acyanotic)
Risk for impaired growth and development
• Treat child as normally as possible
• Teach parents that children are more comfortable
when they know what to expect
• Promote age-appropriate activities as condition
allows
24. Nursing Diagnosis and Care of the
Child with Left-to-Right Shunting
(Acyanotic)
Altered nutrition: less than body
requirements
• Offer small, frequent feedings
• Use soft nipple for infant to ease the
stress
of sucking
• Organize care to allow for rest
25. Nursing Diagnosis and Care of the
Child with Left-to-Right Shunting
(Acyanotic)
Risk for infection
• Limit exposure to individuals with infections
• Promote good pulmonary hygiene
• Prophylactic antibiotics when undergoing
surgical or dental treatment to prevent
subacute bacterial endocarditis