PBL 2 - Co-arctation of the Aorta

Question 1

Where on the aorta does co-arctation most commonly occur? (1 mark)

Answer 1

Adjacent to the ductus arteriosus, (1 mark) (accept just distal to the left subclavian artery)

Question 2

Coarctation of the aorta can lead to incomplete or delayed closing of the aortic valve which produces a murmur during systole. Where is the best place on the chest to auscultate this murmur? (1 mark)

Answer 2

over the right second intercostal space

Question 3

What is the classic sign that almost always indicates co-arctation of the aorta? (1 mark)

Answer 3

Blood pressure differential between upper and lower limbs (or pulse delay between upper and lower limbs)

Question 4

Approximately what proportion of congenital cardiac malformations are associated with co-arctation of the aorta? (1 mark)

Answer 4

Accept any value between 5 & 10%

Question 5

List two other commonly reported congenital vascular deficits in patients with co-arctation (2 marks)

Answer 5

Left heart obstructive defects, ventricular septal defects, bicuspid aortic valve, aortic arch hypoplasia (any two )

Question 6

What form of heart pathology is likely to be visible on an echocardiogram or chest x-ray of a patient with untreated co-arctation? (1 mark)

Answer 6

Enlarged heart

Question 7

What signs would you see on a barium esophagram that would support a diagnosis of co-arctation of the aorta? (2 marks)

Answer 7

Compression of esophagus from dilated left subclavian artery (1 mark) and lower down a second compression from post stenotic dilation of aorta (1 mark)

Question 8

How is aortic co-arctation normally treated? (1 mark)

Answer 8

Surgical repair (resection of narrowed region)

Question 9

What are two symptoms seen in babies with coarctation of the aorta (2)

Answer 9

Congestive heart failure
Severe acidosis
Heavy and/or rapid breathing.
Poor feeding.
Cold feet - poor perfusion to lower body

Question 10

What are 3 symptoms seen in older patients with co-arctation of the aorta (3)

Answer 10

Headache, nosebleed, cramps
Hypertension in head and upper limb, reduced perfusion of lower limb
Systolic murmur heard in the back – faster blood flow in narrowed area

Question 11

What causes a heart murmur and where can you hear it in a patient with COA? (1)

Answer 11

Heard in the back

Faster blood flow in narrowed area

Question 12

What 2 diagnostic tests can you do in COA and what would they show? (2)

Answer 12

• Barium Oesophagus – dilated left subclavian artery + dilation of post stenotic descending aorta shows E sign
• CXR shows cardiac enlargement (ventricular hypertrophy-ventricles need to work harder to squeeze blood past narrowing), pulmonary venous congestion. Rib notching, dilation of internal and intercostal arteries
• Echocardiography- Estimate pressure gradient, find out size and location and severity + any associated abnormalities.

Question 13

What are 2 types of surgery you can do to repair COA and how are they done? (2)

Answer 13

• Surgery – resection with end-to-end anastomosis,
• Balloon dilation (angioplasty) and or stenting
• Bypass graft repair

Question 14

Describe the histological appearance of the aorta is COA. (1)

Answer 14

coarctated segment - intimal and medial lesion consisting of thickened ridges that protrude posteriorly and laterally into the aortic lumen
.The ductus (ie, patent embryonic remnant) inserts at the same level.
Intimal proliferation and disruption of elastic tissue may occur distal to the coarctation. At this site, infective endarteritis, intimal dissections, or aneurysms may occur.
Cystic medial necrosis occurs commonly in the aorta adjacent to the coarctation site and acts as a substrate for late aneurysm formation or aortic dissection in some patient

Question 15

3 Complications of COA (2)

Answer 15

aortic stenosis, myocarditis, VSD, hypoplastic LH, bicuspid aortic valve (85%)

Question 16

Why is there a difference in BP between Jonathan’s arms and legs? (2)

Answer 16

• Because there is narrowing of the aorta between the upper-body artery branches and the branches to the lower body

Question 17

Why is Jonathan tired during exercise/get leg cramps? (2)

Answer 17

• Not enough blood pumped around the body (particularly to legs), therefore not enough oxygen to the muscles so not enough energy
• Poor blood supply to lower limb

Question 18

Define a systolic murmur (1)

Answer 18

CoA –> aortic stenosis –> incomplete/delayed closing of aortic valve –> murmur during systole –> RIGHT 2ND INTERCOSTAL SPACE.

Question 19

What is the prognosis for COA like? (2)

Answer 19

• Untreated/late treatment – heart failure, infective endocarditis, aortic aneurysm
• Early – 91 percent survival, later repair/diagnosis- 79 percent 20 year survival.

Question 20

What is the embryonic abnormality causing COA?

Answer 20

Abnormality in development of the embryologic

left fourth and sixth aortic arches

Question 21

What syndrome is coA linked to in females

Answer 21

Turners

Question 22

How do you diagnose CoA

Answer 22

physical examination.
Blood pressure differential between upper and lower limbs and pulse delay are pathognomonic.
Late systolic murmur