IOD Aortic Dissection

Question 1

Definition?

Answer 1

Aortic dissection occurs when there is a tear in the intima. A split forms in the media and blood tracks in the newly formed ‘false lumen’.

Question 2

CP?

Answer 2

tearing pain bt shoulder blades

asymmetrical

Question 3

classification?

Answer 3

Aortic dissections are classified into type A and type B:
• type A dissection involves the ascending aorta.
• type B dissection does not involve the ascending aorta.
Type A dissections are generally more serious than type B dissections and so the management of type A dissections is more aggressive:
• type A dissections generally require immediate surgical repair.
• type B dissections generally are managed medically (rigorous BP control) with surgery reserved for if there are complications.

Question 4

how does it cause disease?

Answer 4

• the false lumen reduces the blood flow through the ‘true’ lumen. The dissection may extend into other arteries and cause ischaemia/infarction of the organ supplied by that artery.
• the dissection may rupture externally into the pleural cavity, pericardial space or abdominal space.

Question 5

complications-type A?

Answer 5

In a type A dissection, the false lumen may compromise blood flow along branches of the aorta as it spreads along its length: eg. carotid dissection → stroke, coronary dissection → MI.
The dissection may track back to the root of the aorta and rupture into the pericardium, causing cardiac tamponade. Also, a dissection involving the root of the aorta may cause stretching of the aortic valve, leading to the onset of acute aortic regurgitation.
The dissection may rupture externally into the thoracic or abdominal cavity, causing exsanguination.

Question 6

Complications-type B?

Answer 6

rupture
renal failure
gut ischaemia
lower limb ischaemia