16. TEE of the Thoracic Aorta

Question 0

Thoracic aneurism classification

Answer 0

Type 1: proximal descending thoracic aorta to above renal arteries
Type 2: proximal descending thoracic aorta to below renal arteries
Type 3: originates in distal descending aorta
* below sixth intercostal space
Type 4: involves most of abdominal aorta

Question 1

When should a thoracic aneurism be handled surgically?

Answer 1

• 5 cm diameter or more

- diameter more than two times that of a normal segment of aorta

Question 2

Aortic dissection classification

Answer 2

• Stanford -
  Type A: involves ascending aorta
  Type B: confined to descending aorta
• DeBakey -
  Type 1: originates in ascending and involves descending aorta
  Type 2: confined to ascending aorta
  Type 3: originates distal to left subclavian artery

** same classifications for intramural hematomas **

Question 3

Most common sites for intimal tear in aortic dissection

Answer 3

1-3cm above the sinus of vasalva (70%)

Site of ligamentum arteriosum in descending aorta (20-30%)

Question 4

True vs false lumen

Answer 4

• true lumen usually expands during systole and collapses during diastole
• true lumen has a thin, less echodense inner layer vs bright echogenic layer adjacent to the aortic lumen
• if tear is small, false lumen forward flow may occur later in systole vs true lumen (may be same if large tear)
• spontaneous echo contrast in false lumen is possible

Question 5

Intramural Hematoma

Answer 5

• rupture of the vaso vasorum causing hemorrhage into the vessel wall
• thickened aortic wall without an intimal flap or dissection entry site
• 60% of patients progress to dissection or rupture within 1 year (usually ruptures in days if ascending aortic involvement)

Question 6

Aortic atheroma grading

Answer 6

1: normal
2: intimal thickening
3: 5mm (six fold increased risk of stroke, double mortality in hospital)
5: mobile (25% incidence of stroke vs 2% for others)