Stroke Prevention Part 2

Question 1

4 main causes of ischemic stroke

Answer 1

Large artery atherosclerosis (20%)
Small vessel lacunar stroke (25%)
Cardioembolism (20%)
Cryptogenic (30%)

Question 2

What imaging needs to be done after a high risk TIA?

Answer 2

Image the brain: CT head or MRI

Image the blood vessels” CT angio or carotid ultrasound

Question 3

If you have symptomatic carotid artery stenosis, is it better to have surgical or medical management?

Answer 3

Surgical

Question 4

What percentage of stenosis is recommended to have CEA?

Answer 4

50-99%

Question 5

When should you have CEA following TIA/stroke?

Answer 5

In the first 2 weeks

Ideally within 48 hours though

Question 6

2 options available for revascularization

Answer 6

Endarterectomy (surgery)

Stenting

Question 7

Carotid stenting

Answer 7

Pass stent through the plaque and then open it to allow blood flow
Increased risk of stroke compared to CEA because you can dislodge the clot
Decreased risk of periprocedural MI
Nonsignificant increase in mortality
Don’t need general anesthetic

Question 8

When should you use CEA vs CAS?

Answer 8

CEA: first line for moderate to severe symptomatic carotid stenosis
CAS: may be preferable is there is a high perioperative cardiac risk, a previous CEA, radiation, or difficult anatomy

Question 9

How do we treat asymptomatic carotid stenosis?

Answer 9

Medical management

Surgery on a case by case basis (clinical trials currently)

Question 10

How does atrial fibrillation cause a stroke?

Answer 10

A clot forming within the left atrial appendage during irregular flow of Afib leads to embolization of this clot up to the brain

Question 11

CHADS2

Answer 11

Calculating stroke risk in someone with Afib
C: CHF
H: HTN
A: Age > 75
D: Diabetes
S: stroke/TIA (2 points)
Once you have a score of 1 or higher, you’ll benefit from anticoagulation therapy

Question 12

CHADS-VAS

Answer 12

Calculating stroke risk in someone with Afib
C: CHF
H: HTN
A: Age > 75 (2 pt), 65-74 (1 pt)
D: diabetes
S: stroke/TIA (2 pts)
Va: vascular disease
S: sex (Female = 1pt)
Should be started on an anticoagulation therapy once you're 2 or higher

Question 13

New anticoagulation therapies

Answer 13

They have been shown to reduce the risk of TIA and stroke about the same amount as warfarin
Significantly lower intracranial hemorrhage though
Less interactions with meds and food
Way more expensive though
No difference in major bleeding compared to aspirin

Question 14

Warfarin

Answer 14

INR monitoring required
Once daily dosing
Multiple drug interactions
More ICH
Reversible
Liver metabolism
Cheap!
Dose dependent on INR

Question 15

Direct oral anticoagulants

Answer 15

Ex: rivaroxaban, dabigatran, apixaban, edoxaban
No need for monitoring
Once or twice daily dosing
Less drug interactions
Less ICH
Soon to be reversible (some mAbs out there)
Renally excreted
Expensive
Dose dependent on age and renal function

Question 16

2 secondary stroke mechanisms you don’t want to miss

Answer 16

Symptomatic carotid artery stenosis

Atrial fibrillation