Ischemic Disease Pt2 Dr. Stewart

Question 1

How does an ischemic injury manifest in an ECG?

Answer 1

-ST-segment elevation (distance between the S and T wave)
-ST-segment depression
-T-wave inversion
-may cause no ECG changes

-may indicate a severe ischemic injury or an ongoing infarction

Question 2

Difference between STEMI and NSTE-ACS?

Answer 2

-STEMI: ST-elevation MI
ischemic injury with an ST-elevation
-total occlusion -> causing infarction (tissue death)
chest pain at rest -> needs to go to the ER

-NSTE-ACS: no ST-elevation still an urgent event,
no infarction, no necrotic tissue
partial occlusion
chest pain at exertion
PCP referral

Question 3

Types of blood clot

Answer 3

-Red clot: DVT or PE –> anticoagualnt

-White clots: arteriosclerosis causing MI, stroke, PAD -> use antiplatelets

Question 4

What are the drugs used for early treatment in ACS?

Answer 4

early: MONA
Morphine: with severe pain (also it will relax the patient -> relaxes the parasympathetic NS (and the heart) -> less oxygen needed for the heart

Oxygen: (only if they actually need it >90%, infusing it too rapidly can cause oxidative damage)

Nitroglycerin: paste on the chest or continuous infusion

Aspirin: can be given right away (pharmacy), 1x full dose (325 mg) + in the ER they would also get heparin

Question 5

What are the drugs used for late treatment (home meds) in ACS?

Answer 5

SAAB

Statin (new studies: give it earlier)
ACEi: after the patient has stabilized, within 24 hr
Aspirin or DAPT
BB

Question 6

What is the dose for Morp

Answer 6

-2 mg every 15 min PRN for chest pain

-only as much as needed -> could affect the absorption of antiplatelets or other drugs
-can decrease gut motility, cause N/V and impact absorption

Question 7

What are possible ADRs when given O2?

Answer 7

-only given when O2 <90% (when patients really need it)

when given with O2 >90%
-Increases arterial resistance (coronary and SVR)
-Reduces CO
-Reactive oxygen species (free radicals)

Question 8

MOA of Nitroglycerin

Answer 8

-more venodilator -> reduces preload (volume at the end of diastole - the heart is filling after contraction)

-nitric oxide causing vasodilation of smooth muscles of arteries and veins (more veins)

-when blood vessels spasm or constrict -> help to reduce O2 demand through vasodilation

-titrate to chest pain relief

Question 9

What are the ADRs of nitroglycerin?

Answer 9

-Hypotension
-Headache (caused by vasodilation)
-lightheadedness/dizziness
-Nausea
-reflex tachycardia

Question 10

Which drug is contraindicated with nitroglycerin?

EXAM

Answer 10

-PDE-5 inhibitor (sildenafil, tadalafil -> erectile dysfunction)

-artery is blocked and the myocardia doesn’t get enough blood
-2 vasodilator will further decrease the BP and perfusion -> heart attack

Question 11

What are the doses (chronic and acute) for Aspirin in ACS?

Answer 11

Acute: 325 mg

Chronic: 81 mg preferred (75-100 mg) for lifetime

MOA: Inhibits platelet aggregation via TXA2 pathway

Question 12

What are the types of ACS?

Answer 12

-STEMI treatment:
*primary PCI vs fibrinolytic therapy (if PCI is not available)

-NSTE-ACS treatment
aggressive or conservative
*medical therapy
*PCI
*CABG

Question 13

PCI drugs

Answer 13

-Aspirin (already administered in the ER)

-Anticoagulants (d/c after PCI)
*UFH + GP IIb/IIIa (Eptifibatide, Abciximab - potent antiplatelet) -> preferred
*LMWH + GP IIb/IIIa
*Bivalirudin (direct thrombin inhibitor, fe dabigatran can be given w/o GP IIa/IIIb)

-Antiplatelets
GP IIb/IIIa (see above)
*P2Y12i: loading dose after known anatomy

Question 14

Which drug is released by a drug-eluting stent?

Answer 14

-PCI: insertion of a balloon opening the vessel, and inserting the drug-eluting stent

-Immunosuppressant release for about 6 months
-the metal causes an immune reaction and it can cause scaring of the blood vessel

-after time the tissue should nicely overgrowth the stent -> so it doesn’t cause a reaction later (if that doesn’t occur and they stop their DAPT it can cause ACS)

-reduces the risk of thrombosis occurring in the stents

Question 15

Risk reduction with drug-eluting stents

Answer 15

-reduced risk of in-stent thrombosis
-increased risk of late stent thrombosis

Question 16

Why is the artery anatomy being checked before loading the patient with P2Y12 inhibitors?

Answer 16

-bc a loading dose blocks antiplatelet activity for 3-5 days
-they would not be able to undergo surgery -> so their arteries have to be checked (anatomy) before loading them to see if they need a surgery

Question 17

P2Y12 inhibitor - Clopidogrel dosing in PCI therapy

Answer 17

Clopidogrel
– Loading dose: 300-600 mg
– Maintenance dose: 75 mg daily

Question 18

P2Y12 inhibitor - Ticagrelor dosing in PCI

Answer 18

Ticagrelor (Brilinta)
– Loading dose: 180 mg
– Maintenance dose: 90 mg twice daily

Question 19

P2Y12 inhibitor - Prasugrel dosing in PCI

Answer 19

Prasugrel (Effient)
– Loading dose: 60 mg
– Maintenance dose: 10 mg daily

Question 20

Which of the antiplatelets are reversible P2Y12 agents?

Answer 20

-Clopidogrel
-Prasugel

longer half-life, but the effect is related to the lifetime of the platelets
-> since it is irreversible the platelet recovery (effect of the drug) is longer compared to ticagrelor

Question 21

Which of the P2Y12 agents are metabolized through CYP2C19?

Answer 21

Clopidogrel (Plavix) and Prasugrel (Effient)
-both irreversible, given once a day

Question 22

Why is Ticagrelor (Brilianta) given twice a day?

Answer 22

-bc it is reversible and the platelet recovery time is shorter

-benefit: patients on ticagrelor undergo surgery (if they need one, fe bypass) faster than patients on Prasugrel, bc the platelet recovery time is shorter

FYI: there is an assay that helps determine the levels of platelets to tell if the patient is ready to undergo surgery

Question 23

Which of the P2Y12 inhibitors are contraindicated for stroke?

Answer 23

Prasugrel (Effient)
-potent antiplatelet
-it didnt show to have any benefit for stroke prevention, but it increases the risk for bleeding

Question 24

Which if the P2Y12 antiplatelets are the most potent ones?

Answer 24

-new agents are more potent
-Prasugrel (Effient), Ticagrelor (Brilianta)

Question 25

When are the newer P2Y12 agents used?

Answer 25

-post PCI

-Prasugrel and Ticagrelor

Question 26

Which antiplatelets are used for maintenance therapy?

Answer 26

-Aspirin
-if ASA allergy -> Clopidogrel

Question 27

What role do GP IIb/IIIa inhibitors have?

Answer 27

-reduces risk of acute restenosis/thrombosis in PCI patients

-Abciximab (Reopro) (monoclonal Ab): preferred in STEMI
-eptifibatide
-Tirofiban

Question 28

ADR of Abciximab

Answer 28

-delayed Thrombocytopenia (weeks after having a stent)
-hypersensitivity -> leading to Thrombocytopenia?
-higher risk for hypersensitivity and thrombocytopenia with the second dose

Question 29

How is eptifibatide different from Abciximab?

Answer 29

needs dose adjustment
if CrCl <50: reduce from 2 to 1 mcg/kg/min

Question 30

What are the preferred anticoagulants for PCI treatment?

Answer 30

-UFH “normal heparin”
-Bivalirudin (for STEMI and NSTE-ACS with early invasive strategy)

-do not use with GP IIa/IIIb

Question 31

What are the discharge meds?

SELECT ALL THAT APPLY Q
Check what is indicated and what is contraindicated!!

Answer 31

SAAB
Statin -> given earlier: plaque-stabilizing and anti-inflammatory properties during acute reaction
ASA (+P2Y12 if PCI = DAPT - reevaluate P2Y12 after 1 year)
ACEi/ARB: reduces the risk of a 2nd event
BB: reevaluate after 1 year

+ Nitroglycerin SL prn
Eplerenone (technically Spironolactone is acceptable) (if LVEF <40%) - has to be started in the first 7 days for the benefit

Question 32

Which drugs should patients be on for their lifetime?

Answer 32

-Aspirin
-ACEi/ARB: if they have a cardiovascular disease and had an event

-BB: reevaluate after 1 year, keep it they have another indication: like heart failure
-reevaluate P2Y12i after 1 year

Question 33

Duration of DAPT therapy post-MI

Answer 33

-most commonly 12 months (often no benefit after a year) -> when they need a PCI

-patients with stable ischemic disease getting a stent -> at least 6 months unless there is no bleeding risk (should stop at 6 months if bleeding risk ); they often end up being on DAPT for a year

-in patients with bleed and high bleeding risk: consider stopping after 3 months