Session 4- congenital heart disease Flashcards
What is an atrial/ septal defect?
Is a patent foramen ovale an ASD?
An abnormal opening between the L and R atria/ ventricles.
No bc it’s relatively common and mostly asymptomatic due to higher pressure on the left side forcing it closed
What are the effects of a chronic L>R shunt due to ASD or VSD?
There’s more blood in the pulmonary circulation than normal
- R ventricle hypertrophy
- Damaged pulmonary vessels
Most common place for an ASD to occur?
Ostium secundum
A patent foramen ovale is usually asymptomatic, but what serious condition could it cause?
Paradoxical embolus and stroke
A blood clot from the veins could enter the arterial circulation through the PFO and be pumped into the systemic circulation. potentially causing occlusion of a vessel in the brain
Clotting in the veins occurs continuously, why are they not pumped into the arterial circulation?
Filtered out by capillaries in the lungs (pulmonary circulation)
Which foetal shunt can cause Eisenmenger Syndrome if it persists after birth?
Why?
PDA, persistent ductus arteriosus
Chronic L > R shunt creates pulmonary hypertension and eventual reversal of the shunt to cyanotic (R >L)
What is Eisenmenger syndrome?
What can cause it?
Reversal of a chronic L > R shunt to a cyanotic R >L shunt due to hypertension of the pulmonary circulation
Any chronic L >R shunt
- PDA
- ASD
- VSD
What are the femoral pulses and blood pressure like in a patient with coarctation of the aorta?
Explain why.
- Weak, delayed femoral pulses
- Hypertension in upper body
- Hypotension in lower body
The vessels leading to the head and upper limbs emerge close to the narrowing (coarctation) so their blood supply is unaffected. Blood flow to the rest of the body is reduced
In which region does aortic coarctation occur?
The narrowing causes left ventricular hypertrophy, why?
the ligamentum arteriosus (previously the ductus arteriosus)
Increases the afterload on the L ventricle
How does tetralogy of fallot present?
What determines its severity?
Cyanosis or spells of cyanosis in infancy
How severe the pulmonary stenosis is (less blood leaving the right ventricle means more is pumped into systemic circulation by the overriding aorta)
Transposition of the great arteries is fatal after birth, why?
The foramen ovale closes which has allowed oxygenated blood to enter the right atrium and be pumped to the rest of the body
When it closes, only deoxygenated blood (from the R ventricle) enters systemic circulation
The heart is described as two pumps in series. How does this change in transposition of the great arteries?
Becomes two parallel uncommunicative pumps
In hypoplastic left heart, the L ventricle and ascending aorta don’t develop properly.
How then does blood reach the systemic circulation?
Why is this condition fatal without surgery?
Blood enters the aorta through a patent ductus arteriosus as less enters due to ventricular contraction
Because deoxygenated blood is supplying the systemic circulation
What is tricuspid atresia?
How is blood flow achieved?
Lack of a tricuspid valve
(no communication between R atrium and R ventricle)
- patent foramen ovale/ ASD between atrium
- VSD or patent ductus arteriosus to send blood to the lungs
