3. Atrial Septal Defect
An atrial septal defect (ASD) is a hole in the heart between the upper
chambers (atria). The hole increases the amount of blood that flows
through the lungs. The condition is present at birth (congenital heart
defect).
Small atrial septal defects might be found by chance and never cause a
concern. Others close during infancy or early childhood.
A large, long-term atrial septal defect can damage the heart and lungs.
Surgery may be needed to repair an atrial septal defect and to prevent
complications.
4. Pathophysiology
in Atrial septal defect, the hole in the atrial septum allows oxygen-rich
blood to flow from the left atrium to the right atrium, resulting in
increased blood flow to the lungs. This leads to an increase in blood
pressure in the lungs, which over time can lead to lung stiffness and
problems with breathing.
Additionally, the increased blood flow to the lungs can lead to an
increased risk of infection and an overworking of the right ventricle, which
may cause it to enlarge. This can lead to right heart failure over time
The oxygen-poor blood from the body also mixes with oxygen-rich blood
which decreases the oxygen saturation in the body's blood which can lead
to cyanosis and other symptoms.
5. Causes
The cause of atrial septal defect is unclear. Atrial septal defect is a structure
problem that occurs during heart development while a baby is still in the
womb.
Genetics, certain medical conditions, use of certain medications, and
environmental or lifestyle factors, such as smoking or alcohol misuse, may
play a role.
6. Types of Atrial Septal Defect
There are several types of atrial septal defects, including:
Ostium secundum ASD, which is the most common type of ASD and
occurs the opening in the middle of the atrial septum.
Ostium primum ASD, which occurs the opening in the lower part of the
atrial septum.
Sinus venosus ASD, which occurs the opening is near the junction of the
superior vena cava and the right atrium.
7. Symptoms
Atrial septal defect signs and symptoms can include:
Shortness of breath, especially when exercising
Fatigue Swelling of legs, feet or belly (abdomen)
Irregular heartbeats (arrhythmias)
Sensation of a rapid, pounding heartbeat (palpitations) or skipped beats
Whooshing sound that can be heard through a stethoscope (heart
murmur)
8. Risk factors
Atrial septal defect (ASD) occurs as the baby's heart is developing during
pregnancy. Certain health conditions or drug use during pregnancy may
increase a baby's risk of atrial septal defect or other congenital heart defect.
These things include:
German measles (rubella) infection during the first few months of pregnancy
Diabetes
Lupus
Alcohol or tobacco use
Illegal drug use, such as cocaine
Use of certain medications, including some anti-seizure medications and drugs
to treat mood disorders
9. Complications
A small atrial septal defect might never cause any concern. Small atrial
septal defects often close during infancy.
Larger atrial septal defects can cause serious complications, including:
Right-sided heart failure
Irregular heartbeats (arrhythmias)
Stroke
Early death
High blood pressure in the lung arteries (pulmonary hypertension)
10. Diagnosis
Tests that are done to help diagnose an atrial septal defect include:
Echocardiogram.
Chest X-ray.
Electrocardiogram (ECG or EKG).
Cardiac magnetic resonance imaging (MRI) scan.
Computed tomography (CT) scan.
11. Treatment
Medications : Medications won't repair an atrial septal defect, but they can help
reduce signs and symptoms. Medications for atrial septal defect might include
drugs to control the heartbeat (beta blockers) or to reduce the risk of blood
clots (anticoagulants).
Surgery or other procedures :
Catheter-based repair.: A thin, flexible tube (catheter) is inserted into a blood
vessel. A plug is passed through the catheter and used to close the hole. Heart
tissue grows around the seal, permanently closing the hole (used only for the
secundum type).
Open-heart surgery : This type of atrial septal defect repair surgery involves an
incision through the chest wall to access the heart directly. The surgeons use
patches to close the hole. This open-heart repair surgery is the only way to fix
primum, sinus venosus and coronary sinus atrial defects.
12. Management
Nutrition: many patients have decreased growth because of the decrease
cardiac output (heart failure)…calculating caloric intake, weights, educated
about nutrition, patient may be a candidate for a feeding tube “risk for
imbalance nutrition”
Heart rhythm: at risk for dysrhythmias, monitor rhythm, heart sounds,
signs of heart failure “decreased cardiac output”, “activity intolerance”
Hespiratory: monitor lungs sounds for crackles (indicate fluid overload),
education about risk of frequent respiratory infections (vaccines to
prevent, especially childhood vaccines) “risk for infection)
13. References
M. C. S. (2022, March 1). Atrial septal defect (ASD). Mayoclinic.
https://www.mayoclinic.org/about-this-site/meet-our-medical-editors.