PBL 2 - Co-arctation of the Aorta Flashcards
Where on the aorta does co-arctation most commonly occur? (1 mark)
Adjacent to the ductus arteriosus, (1 mark) (accept just distal to the left subclavian artery)
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)
over the right second intercostal space
What is the classic sign that almost always indicates co-arctation of the aorta? (1 mark)
Blood pressure differential between upper and lower limbs (or pulse delay between upper and lower limbs)
Approximately what proportion of congenital cardiac malformations are associated with co-arctation of the aorta? (1 mark)
Accept any value between 5 & 10%
List two other commonly reported congenital vascular deficits in patients with co-arctation (2 marks)
Left heart obstructive defects, ventricular septal defects, bicuspid aortic valve, aortic arch hypoplasia (any two )
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)
Enlarged heart
What signs would you see on a barium esophagram that would support a diagnosis of co-arctation of the aorta? (2 marks)
Compression of esophagus from dilated left subclavian artery (1 mark) and lower down a second compression from post stenotic dilation of aorta (1 mark)
How is aortic co-arctation normally treated? (1 mark)
Surgical repair (resection of narrowed region)
What are two symptoms seen in babies with coarctation of the aorta (2)
Congestive heart failure Severe acidosis Heavy and/or rapid breathing. Poor feeding. Cold feet - poor perfusion to lower body
What are 3 symptoms seen in older patients with co-arctation of the aorta (3)
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
What causes a heart murmur and where can you hear it in a patient with COA? (1)
Heard in the back
Faster blood flow in narrowed area
What 2 diagnostic tests can you do in COA and what would they show? (2)
- 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.
What are 2 types of surgery you can do to repair COA and how are they done? (2)
- Surgery – resection with end-to-end anastomosis,
- Balloon dilation (angioplasty) and or stenting
- Bypass graft repair
Describe the histological appearance of the aorta is COA. (1)
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
3 Complications of COA (2)
aortic stenosis, myocarditis, VSD, hypoplastic LH, bicuspid aortic valve (85%)