PAD

Question 1

What is the most common symptoms of PAD (2)?

Answer 1

• intermittent claudication

- pain in lower extremities at rest

Question 2

What is first line treatment for PAD?

Answer 2

-exercise (supervised )

Question 3

What are the Fontaine classification of PAD (6)?

Answer 3

I:asymptomatic
II: mild-no limitation with walking
IIa: moderate IC with more than 2 blocks
IIb: severe, IC with walking less than 2 blocks
III: ischemic pain at rest, limited blood flow
IV: ulceration/gangrene-no blood flow

Question 4

What are the recommended treatments for the the levels of PAD/Fontaine classification?

Answer 4

All patients with PAD-give statins
I- aspirin 75-325 mg/day or clopidogrel 75mg/day, use anti-hypertensive, can use Cilostazol
IIa-if ABI<0.9 give aspirin, use ACE/ARB for HTN
IIb: if ABI 0.91-0.99 aspirin benefit uncertain
IIb: dual anti-platelet therapy uncertain
III: don’t use pentoxifylline or chelation therapy or oral anti-coagulation

Question 5

Which factors promote platelet aggregation (3)?

Answer 5

• ADP
• serotonin
• TAX2

Question 6

Where does GPIA bind? GPIB?GPIIA/IIIB?

Answer 6

GPAI- binds collagen
GPIB: binds vWF
GPA IIA/IIIB binds fibrin

Question 7

Which factors stop platelet aggregation?

Answer 7

prostacyclin/PGI2-binds receptors on platelets

• works against TAX2
• NO( nitric oxide induces vasodilation)

Question 8

what happens when there is defect in the endothelium?

Answer 8

1. PGI2 and NO no longer produced and vessel constricts
2. platelets become activated and bind collagen and vWF
3. platelets release ADP, TAX2, serotonin/5-HT, and PAF
4. released chemicals induce more platelet aggregation
5. Extrinsic and Intrinsic pathway are activated and form factor XA which is converted into thrombin and thrombin forms fibrin
6. Receptor GPIIA/IIIB binds fibrin and cross links platelets together

Question 9

What is MOA of aspirin?

Answer 9

-blocks enzyme COX 1 which irreversibly inhibits prostaglandin H2 and stops TXA2 which stops platelet activation and aggregation

Question 10

What are side effects to aspirin?

Answer 10

• GI bleeds

- Gastric Ulcers

Question 11

Why give a low dose aspirin? What is the low dose range?

Answer 11

• low dose preferentially blocks TXA2 and leaves behind prostaglandins
• low dose range: 75mg-325mg

Question 12

What are contraindications of aspirin (3)?

Answer 12

• active bleeding
• hemophilia
• thrombocytopenia

Question 13

T/F Ibuprofen is reversible while aspirin is irreversible

Answer 13

True

Question 14

What is the lifetime of a platelet?

Answer 14

7-10 days

Question 15

How many days should a patient stop taking aspirin before a surgery?

Answer 15

10 days

Question 16

Name 2 functions of TXA2?

Answer 16

• potent vasoconstriction

- promotes platelet aggregation

Question 17

What is MOA of clopidogrel?

Answer 17

• irreversibly blocks ADP receptors on platelets to inhibit activation of GP IIa/IIIb stopping fibrin cross linking between platelets
• blocks platelet aggregation

Question 18

What are side effects of clopidogrel (3)?

Answer 18

• chest pain
• purpura
• generalized rash

Question 19

what are the contraindications of clopidogrel (2)?

Answer 19

• intracranial hemorrhage

- active bleeding

Question 20

What is MOA of Cilostazole (2)?

Answer 20

• blocks PDE-III which stops degradation of cAMP(increased) which decreases intracellular calcium and stops platelet activation and aggregation
• direct artery vasodilator

Question 21

what are side effects of cilostazole (5)?

Answer 21

• headache
• dizziness
• diarrhea
• tachycardia
• fever-infection

Question 22

What are contraindications for cilostazole?

Answer 22

-CHF patients

Question 23

If a patient cant take aspirin, what do you give?

Answer 23

-clopidogrel

Question 24

what do give for IC?

Answer 24

-Cilostazole

Question 25

What is MOA of pentoxifylline

Answer 25

- alters RBC flexibility so platelets can't attach - reduces blood viscosity - decreases fibrinogen concentration

Question 26

What are side effects of pentoxifylline (4)?

Answer 26

- headache - dyspnea - nausea - vomiting

Question 27

What are contraindications of pentoxifylline (2)?

Answer 27

- recent retinal and cranial bleeds | - active bleeding

Question 28

T/F Pentoxifylline is recommended in IC

Answer 28

False

Question 29

What is MOA for dypiramidole?

Answer 29

same as - blocks PDE-III, increases cAMP and decreases intracellualr calcium - stops platelet activation and aggregation - direct artery vasodilator -adenosine?

Question 30

What are side effects of dypiramidole?

Answer 30

- angina | - hypotension

Question 31

What is contraindication for dypiramidole (2)?

Answer 31

- CAD | - active bleeding

Question 32

What is MOA for vorapaxar?

Answer 32

-irreversibly binds PAR-1 receptor and blocks thrombin mediated platelet aggregation -lasts up to 4 weeks after stopping -

Question 33

what are side effects of vorapaxar (4)?

Answer 33

- iron deficiency - rash - depression - >10% bleed,

Question 34

Contraindications for Vorapaxar?Black box warning? (5)

Answer 34

- hx of stroke - surgical patients - active bleed - intracranial hemorrhage - hepatic/renal impairment

Question 35

What should you monitor for patients taking Vorapaxar?

Answer 35

H&H

Question 36

T/F Vorapaxar is best used as mono therapy and never combined with aspirin or clopidogrel

Answer 36

False: never used as mono therapy

Question 37

If patient has no improvement with initial tx, what should you consider?

Answer 37

3 month trial of cilostazole