CVS Congenital heart disease

Question 1

What are the causes of congenital heart disease?

Answer 1

Genetic e.g. Down’s, turner’s, marfan’s
Environmental e.g. alcohol, drugs
Maternal infections eg rubella

Question 2

List the possible shunts:

Answer 2

Atrial (asymptomatic late into adulthood)
Ventricular (left heart failure)
Atrio-ventricular
Aorto-pulmonary

Question 3

How is congenital heart disease classified?

Answer 3

Acyanotic: (normal blood O2 conc)

• left to right shunts
• atrial septal defects (failure of foramen ovale to close)
• ventricular septal defects (usually membranous portion)
• patent ductus arteriosus (fails to close)
• coarctation of aorta

Cyanotic: (low blood O2 conc)

• complex
• right to left shunts (needs a hole and distal obstruction)
• tetralogy of fallot
• tricuspid atresia
• transposition of great arteries
• hypoplastic left heart

Question 4

What are the consequences of:

Atrial septal defects

Ventricular septal defects

Answer 4

Atrial septal defects:
L-->R shunt
Failure of foramen ovale to close
There is increased pulmonary blood flow (can lead to, but rare, pulmonary hypertension)
RV overload
Eventual right heart failure

Ventricular septal defects:
L-->R shunt 
Most commonly in membranous portion 
Leads to pulmonary venous congestion and eventually pulmonary hypertension
LV overload

Question 5

Describe the condition of Tetralogy of Fallot

Answer 5

Group of 4 lesions:

• pulmonary stenosis
• ventricular septal defect
• RV hypertrophy
• overriding aorta

R–>L shunt resulting in cyanosis

Question 6

Describe the condition of Tricuspid atresia

Answer 6

Lack of development of tricuspid valve so no RV inlet
Right to left atrial shunt of entire venous return
Blood flow to lungs via ventricular septal defect or patent ductus arteriosus

Question 7

Describe the condition of Hypoplastic left heart

Answer 7

The LV is underdeveloped
Ascending aorta v small
Atrial septal defect also present

RV supports systemic circulation

neonatal emergency

Question 8

Describe the transposition of the great arteries

Answer 8

2 unconnected circulations:
RV connected to aorta
LV connected to pulmonary artery

Occurs when the septum in the truncus arteriosus does not take its spiral course so the great vessels are connected to the wrong chambers

Not viable unless the two circuits communicate via atrial or ventricular shunts (bi-directional shunting)

Question 9

Describe the condition of Pulmonary atresia

Answer 9

There is no RV inlet
Right to left atrial shunt of entire venous return
Blood flow to lungs via patent ductus arteriosus

neonatal emergency

Question 10

What is a patent ductus arteriosus?

Answer 10

Failure of the ductus arteriosus to close
Leads to blood flow from aorta–>pulmonary arteries
Constant mechanical murmur
If untreated can lead to vascular remodelling of pulmonary circulation, increasing pulmonary resistance.

Question 11

What is coarctation of the aorta?

Answer 11

Narrowing of the aortic lumen in the region of the ligamemtum arteriosum (former ductus arteriosus).

Can lead to LV hypertrophy
Vlood vessels to head and upper limb usually proximal, however vessels to rest of body are effected and blood flow is reduced.

Femoral pulses weak and delayed