Aortic Dissection

Question 0

Why is it important not to get an MI and aortic dissection confused?

Answer 0

The treatment for MI (anticoagulation with heparin or thrombolytics) worsens aortic dissection

Question 1

Patient with aortic dissection. Next steps?

Answer 1

1. Intervenous beta blocker
2. noninvasive imaging procedure (transesophageal echo, CT angiography, MRI)
3. Lower BP if hypertensive

Question 2

Definition of an abdominal aortic aneurysm? Typically occurs where?

Answer 2

Dilation to more than 1.5 times the normal diameter of the aorta. Below the renal arteries.

Question 3

Cystic degeneration affects what layer of the aorta? Occurs in what connective tissue disorders?

Answer 3

Elastic media. Marfan’s and Ehlers-Danlos syndrome

Question 4

Factors predisposing to aortic dissection?

Answer 4

Heart problems: aortic valvular abnormalities,

vessel issues: Cystic degeneration, hypertension, coarctation of the aorta, atherosclerotic disease,

other: pregnancy, surgery or catheterization

Question 5

Dissection occurs when there’s a sudden tear to what layer? Followed by?

Answer 5

Intima. Followed by propagating dissecting hematoma.

Question 6

Most important factors causing the propagation of the dissection?

Answer 6

Hypertension and the associated shear forces

Question 7

How does an aortic dissection cause of organ ischemia or infarction?

Answer 7

Produces an intraluminal intimal flap which can occlude branch arteries

Question 8

Complications from an aortic dissection?

Answer 8

1. Organ ischemia
2. Cardiac tamponade (leads to exsanguination)
3. Acute aortic regurgitation

Question 9

Anginal pain versus pain of dissection? (Course, alleviation)

Answer 9

Builds over minutes versus maximal at onset

Alleviating by nitrates versus not

Question 10

Aortic dissection may cause which murmur?

Answer 10

Early diastolic murmur of aortic sufficiency (especially since most dissections begin close to aortic valve)

Question 11

Blood pressure of most patients with dissection? Otherwise?

Answer 11

Hypertensive. If hypotensive, suspect aortic rupture, cardiac tamponade, dissection of subclavian artery

Question 12

Plain chest film on patient with aortic dissection would likely show?

Answer 12

Widened superior mediastinum

Question 13

Type A versus Type B dissection?

Answer 13

Involves the ascending aorta versus does not involve the ascending aorta

Question 14

Horner syndrome results from?

Answer 14

Compression of the superior cervical ganglion

Question 15

Superior vena cava syndrome results from?

Answer 15

Compression of the superior vena cava

Question 16

Hemopericardium, pericardial tamponade occurs from?

Answer 16

Thoracic dissection with retrograde flow to the pericardium

Question 17

Bowel ischemia hematuria occurs from a dissection involving?

Answer 17

The mesenteric arteries or renal arteries

Question 18

Hypertension or different blood pressures in the arms result from a dissection involving what?

Answer 18

Cardiac dissection involving brachiocephalic artery

Question 19

Hemiplegia results from a dissection involving what?

Answer 19

Carotid artery

Question 20

Most aortic dissection originate where?

Answer 20

A few centimeters above the aortic valve.

Question 21

Treatment for type A dissection? Mortality without accepted treatment?

Answer 21

Surgical therapy with replacement of a order and sometimes aortic valve. 90%.

Question 22

Type B dissections originate where?

Answer 22

In the aortic arch distal to the left subclavian artery

Question 23

Surgery for type B dissections when?

Answer 23

Surgery performed only for complications such as rupture or ischemia of the branch of the aorta

Question 24

Aim of medical therapy?

Answer 24

Prevent propagation of the dissection by reducing mean arterial pressure and rate of rise of arterial pressure (Reduces shear forces)

Question 25

Drugs given for type B dissections?

Answer 25

1. Intravenous vasodilators such as sodium nitroprusside (lowers BP) with beta blockers such as metoprolol (lowers shear forces)
2. Labetalol

Question 26

Symptoms of Thoracic aortic aneurysm versus abdominal aortic aneurysm

Answer 26

Tearing pain radiating to the back versus asymptomatic with midline pulsatile mass

Question 27

Abdominal aortic aneurysm can rupture where? Can lead to?

Answer 27

1. Anteriorly. Patient exsanguinates within minutes

2. Posteriorly. Patient bleeds into retroperitoneum and presents with severe lower back or mid abdominal pain

Question 28

Risk of rupture is related to size of aneurysm. Size to watch for?

Answer 28

Low risk of rupture with 5 cm aneurysm but 10 to 20% risk with 6 cm aneurysms

Question 29

Elective repair of abdominal aortic aneurysms with what size aneurysm?

Answer 29

5.5 cm

Question 30

Recommendations for surveillance of abdominal aortic aneurysm?

Answer 30

Imaging at 3-12 month intervals depending on risk of rupture