ST-Elevation Myocardial Infarction (STEMI)

Question 1

What are some tx strategies for STEMI?

Answer 1

PCI within 90 minutes at facility w cath lab (GOLD standard)

Cath lab within 120 minutes for patients transferred from non-PCI capable facility

Fibrinolytic agent for patients unable to transfer to PCI capable hospital within 120 min

Question 2

What are some early interventions for STEMI?

Answer 2

MONA

Morphine
Oxygen
Nitrates
Aspirin

Question 3

What is morphine used for in STEMI patients?

Answer 3

pain, anxiety, pulmonary edema

Question 4

What is the dosing for morphine?

Answer 4

4-8 mg IV, then 2-8 mg IV q 5-15 minutes PRN

Question 5

Which types of patients should we be careful with use of morphine?

Answer 5

Hypotensive and bradycardic patients and patients w renal failure

Morphine can cause histamine release which can lead to downstream effects of HoTN and bradycardia
Morphine can accumulate in patients w poor renal function

Question 6

Why has morphine been controversial in the past couple years?

Answer 6

Does not reduce mortality, only sx benefit
May decrease P2Y12
Falling out of favor

Question 7

When should oxygen be used?

Answer 7

In hypoxemic patients w SpO2 < 90%
No benefit in patients without hypoxemia

only for sx relief of Shortness of breath

Question 8

If oxygen is used, what is the recommended dose to use?

Answer 8

2-4 L/min nasal cannula, then titrate up to get them > 90% SpO2

Question 9

What are nitrates used for in STEMI patients?

Answer 9

chest pain and HTN

Used for symptomatic relief by reducing LV preload and increased coronary blood flow

Question 10

What dose of nitrate should be used?

Answer 10

Nitroglycerin: 0.4 mg SL q 5 min PRN x 3 doses

Question 11

Which types of patients should we be careful with use of nitrates?

Answer 11

Caution in HoTN, bradycardia and tachycardia

Contraindicated in RV infarction and PDE5 inhibitor use within 24-48 hours

Question 12

What is the dose for aspirin use in STEMI tx?

Answer 12

162-325 mg loading dose prior to PCI
Chew non-enteric coated
Rectal suppository if oral route not available

Question 13

What are some options for P2Y12 inhibitors and the doses?

Answer 13

Clopidogrel 600 mg
- Commonly used in patients w high bleed risk
- Often cheapest option

Prasugrel 60 mg
- Increased bleed risk
- CI in patients w hx of stroke or TIA or active bleed

Ticagrelor 180 mg
- Similar rates of major bleeding compared to clopidogrel
- Twice daily dosing is a downside
- Expensive

Question 14

which P2Y12 inhibitor are preferred?

Answer 14

Ticagrelor and prasugrel preferred over clopidogrel

Question 15

What literatures explore P2Y12 inhibitors to help with choosing which to choose?

Answer 15

TRITON-TIMI trial showed lower rate of primary composite outcome and lower rate of stent thrombosis in prasugrel vs clopidogrel

PLATO trial favored use of ticagrelor over clopidogrel in terms of stent thrombosis and death

Question 16

What is Cangrelor? dose?

Answer 16

IV P2Y12 inhibitor
30 mcg/kg bolus followed by 4 mcg/kg/min infusion
Run for 2 hours or until PCI complete

Question 17

how do you go from IV to oral p2y12?

Answer 17

Stop infusion → administer oral loading dose immediately after dc of drip

Question 18

Why are antiplatelets necessary prior to PCI?

Answer 18

Prevent platelet adhesion and aggregation in early stages of MI
Reduce myocardial damage

Question 19

When should anticoagulation start for STEMI?

Answer 19

Start immediately after dx

Question 20

What are the options for anticoagulation for PCI candidates in STEMI?

Answer 20

heparin and bivalirudin (Heparin drip is preferred)

Question 21

Dose for Heparin?

Answer 21

70-100 unit/kg bolus
Titrate drip based on hospital nomogram

Question 22

Dose for Bivalirudin?

Answer 22

0.75 mg/kg IV bolus
1.75 mg/kg/hr infusion
1 mg/kg/hr infusion for CrCl < 30

Question 23

What is the duration for anticoagulation in STEMI tx?

Answer 23

Bivalirudin continued for 4 hours following PCI
Heparin can be stopped immediately after PCI

Question 24

What are some maintenance meds following PCI?

Answer 24

dual antiplatelet therapy (DAPT)
Beta blocker
ACEi
Statin

Question 25

Doses for DAPT?

Answer 25

Aspirin 81 mg indefinitely PLUS P2Y12 inhibitor x 1 year
Clopidogrel 75 mg daily
Prasugrel 10 mg daily
Ticagrelor 90 mg BID

DAFT After PCI: reduce risk of stent thrombosis, prevent subsequent cardiac adverse effects

Question 26

What are some contraindications for beta blockers?

Answer 26

decompensated HF, low output state, cardiogenic shock, bradycardia, AV block
Continually reassess if Beta blocker can be started

Question 27

Which beta blockers are recommended in the guidelines for STEMI management?

Answer 27

Oral preferred
Start short acting inpatient
Transition to long-acting on discharge

Metoprolol
IR (T): 25-50 mg q 6-12 hours
ER (S): 25-200 mg daily: Titrale to 200 mg as tolerated

Carvedilol
6.25 mg BID
Titrate to 25 mg BID as tolerated

Question 28

Who should be recommended ACEI for STEMI management?

Answer 28

Recommended for all patients w LVEF < 40%
Can be routinely given any patient post-MI unless CI

Question 29

Doses for ACEi in STEMI?

Answer 29

ACEi, starting dose, target dose

Lisinopril
2.5-5 mg daily
10mg daily or higher

Captopril
6.25-12.5 mg TID daily
25-50 mg TID daily

Ramipril
2.5 mg BID
5 mg BID

Trandolapril
0.5 mg daily
4 mg daily

Question 30

What are some contraindications for ACEi?

Answer 30

HoTN, hyperkalemia, renal failure

Question 31

Which statin is indicated for STEMI and what dose?

Answer 31

High intensity statin indicated
Atorvastatin 80 mg recommended by guidelines
Atorvastatin 40-80 mg and rosuvastatin 20-40 mg also reasonable