Congenital - Atrial Septal Defect (ASD) Flashcards
When does atrial septal defect (ASD) occur?
A congenital defect in the interatrial septum that allows blood to move between atria e.g., due to incomplete formation of septum primum/secundum or if the foramen secundum is large
What is the consequence of blood being able to cross to the right atria?
right atria dilation and pulmonary hypertension due to increase load on the right side of the heart may cause right sided heart failure
Are patients initially cyanotic with ASD?
No, as blood gets oxygenated
What may cause a patient with ASD to become cyanotic?
Eventually, pulmonary hypertension can lead to Eisenmenger syndrome. This occurs because the pulmonary pressure exceeds the systemic pressure, causing the shunt to reverse and become a right-to-left shunt across the ASD. This causes blood to bypass the lungs, resulting in the patient becoming cyanotic.
What is the prognosis of ASD?
50% patients dead at 50 years
There are 2 main types of ASD?
Osmium secundum
Osmium primum
Which type of ASD is more common?
Ostium secondum, where the septum secondum fails to fully close, leaving a hole in the wall
Each type of ASD, osmium secundum and premium is associated with specific diseases what are they?
Secudum is associated with Holt-Oram syndrome
Primum is associated with abnormal AV valves
Are children symptomatic usually?
No
What symptoms may adults present with?
- SOB secondary to pulmonary hypertension and high-sided heart failure
- Stroke in context of venous thromboembolism
- AF
Why a patient with ASD can have a stroke?
Normally, when patients have a DVT and this becomes an embolus, the clot travels to the right side of the heart, enters the lungs and becomes a pulmonary embolism. In patients with an ASD the clot can travel from the right atrium to the left atrium across the ASD. This means the clot can travel to the left ventricle, aorta and up to the brain, causing a large stroke.
What murmur is present in atrial septal defect?
Crescendo-decrescendo
What is the management for ASD?
In cases where the ASD is small and asymptomatic, watching and waiting may be appropriate. ASDs can be corrected surgically using a percutaneous transvenous catheter closure (via the femoral vein) or open-heart surgery. Anticoagulants (such as aspirin, warfarin and DOACs) are used to reduce the risk of clots and stroke in adults.
