Atrial Septal Defect Flashcards
What is an Atrial Septal Defect?
A hole in the septum between the left and the right atrium
How many chambers make up the heart? Name them and their role.
The heart has 4 chambers:
Left and Right Atrium - Collects blood
Left and Right Ventricles - Pumps blood out of the heart
What does the septum do?
Seperates the 2 sides of the heart
What do Valves do?
Prevents backflow of blood
Where does the right side of the heart pump blood to?
The right side of the heart pumps de-oxygenated blood to the lungs to pick up oxygen
Where does the left side of the heart pump blood to?
The left side of the heart pumps oxygenated blood from the lungs around the rest of the body
Describe the movement of blood in the pathophysiogy of ASD
Oxygenated blood from the left atrium flows through the hole in the septum into the right atrium, where it mixes with oxygen-poor blood
What does the movement of blood in the pathophysiology of ASD cause and why?
This causes the enlargement of the right atrium, right ventricle, and the pulmonary artery due to the increased blood flow
What is increased blood flow to the lungs called?
Pulmonary hypertension
What sort of sound does an increased blood flow to the lungs cause?
A swishing sound known as a heart murmur
What do the symptoms of an ASD depend on and what is the norm?
The symptoms caused by an ASD depend on its size and its location.
Most kids who have ASDs seem healthy and appear to have no symptoms. Most grow and gain weight normally
List 5 symptoms of larger, more severe ASDs
- Poor Appetite
- Extreme Fatigue
- Poor Growth
- Shortness of Breath
- Lung Problems and Infections e.g. Pneumonia
What causes poor appetite, extreme fatigue, and shortness of breath in ASD
Caused by the decreased O2 levels (Hypoxemia)
What causes lung problems and infections in ASD?
As the lungs receive an increased volume of blood, strain and stress is put on the lungs, making it more susceptible to infection as the increased blood flow could provide an environment for bacteria and other pathogens to grow
What causes poor growth in ASD
A decrease in the amount of oxygen-rich blood being pumped to the rest of the body
What is the importance of diagnostic imaging for ASDs
Diagnostic imaging is important in determining the size of the defect and determining treatment options
What is the main imaging choice for diagnosing ASDs?
A Transthoracic Echocardiogram
List 5 things a Transthoracic Echocardiogram can detect.
- Size of the defect
- Direction of blood flow
- Heart structure and function
- Estimate pulmonary artery pressure
- Estimate the pulmonary/systemic flow ratio
List 3 other diagnostic modalities for ASDs
- Cardiac CT scan
- MRI scan
- Chest X-rays
How do MRIs and Cardiac CTs help to diagnose ASDs?
They examine structures surrounding the heart and in the thoracic cavity
Are chest x-rays helpful diagnostically?
Chest x-rays are not as helpful diagnostically.
What can chest x-rays help monitor?
Chest x-rays help monitor clinical status.
What conditions can chest x-rays identify?
Chest x-rays can identify cardiomegaly and pulmonary artery enlargement.
Can an ASD close on its own?
Yes an ASD may close on its own during childhood
