Myocardial Infarction (+ Sudden Cardiac Death)

Question 1

What is a myocardial infarction - MI?

Answer 1

Heart attack: blockage of blood flow to the heart muscle; sustained ischemia (reduced blood flow) leading to IRREVERSIBLE myocardial death or necrosis (cell death)

**80% are because of blood clots

Question 2

CAD

Answer 2

Coronary Artery Disease

Question 3

What is ATHEROSCLEROSIS?

Answer 3

disease of arteries because of a collection of plaques OR fatty materials on inner walls of those arteries

Question 4

What can ATHEROSCLEROSIS be made of?

Answer 4

• fatty streaks
• fibrous plaque
• lesions

Question 5

What are some risk factors for CAD; and ultimately MI that are NOT MODIFIBLE…

Answer 5

• increased age
• certain ethnicities: white & black
• increased risk for men than women in ages under 75
• genetics
• family hx

Question 6

What are some risk factors for CAD; and ultimately MI that ARE MODIFIBLE….

Answer 6

• smoking
• obesity
• diabetes (type 2)
• physical activity (limited - little)
• HTN
• lipid profile (increased lipids)
• metabolic syndromes

Question 7

What does CAD prevention look like?

Answer 7

**identify patients that are HIGH RISK + offer early management of those modifiable factors to allow for early management of CAD for these patients

Question 8

CARDIAC DIET

Answer 8

• balanced calories
• monitor weight throughout
• smaller meals + more often
• **WHOLE GRAINS + ***HIGH FIBER
• **MORE FRUITS + ***MORE VEGETABLES
• NO sodas, sugary drinks
• **LEAN MEATS
• **SKIM DAIRY
• moderate alcohol intake
• **LOW SALT (2400mg/daily OR less)
• NO deep fried OR limited; bake, broil, grill
• **FISH-OMEGA 3 FATTY ACIDS

Question 9

What is ANGINA?

Answer 9

ischemia (reduced blood flow) causing chest pain;
this is caused by the narrowing of coronary arteries which leads to MYOCARDIUM HYPOXIA (decreased oxygen to cardiac muscles, increased lactic acid) = PAIN;
**can be acute OR chronic

Question 10

How can pain ANGINA pain present?

Answer 10

• chest
• sternum
• neck/jaw
• shoulder/arm
• mid-back
• *Can radiate from any location to any other location

Question 11

Why does an MI have such serious effect on the heart?

Answer 11

ALL heart muscle BELOW the blockage becomes ischemic/necrotic because of LACK OF OXYGENATED BLOOD FLOW reaching that heart muscle; blockage can be complete or even incomplete; incomplete blockages restrict enough blood flow that over time the muscle still dies

Question 12

Ischemia/Necrotic time frame:

Answer 12

**cardiac cells become ischemic 20 minutes BEFORE cell death occurs (once dead = always dead) YOU CANNOT REVERSE THIS: 30 minutes into ischemic attack, the WHOLE HEART BECOMES NECROTIC/DEAD!!!!!!!

Question 13

MI Locations: RT Coronary Artery - RCA

Answer 13

• occlusions lead to heart blocks
• **this artery feeds the POSTERIOR part of the heart
• only MASSIVE infarction of RCA = cardiogenic shock

Question 14

MI Locations: LT Main Coronary Artery - Left Main

Answer 14

**VERY THIN, TINY and QUICKLY leads to sudden death > Widow Maker

Question 15

MI Locations: LT Anterior Descending - LAD

Answer 15

• leads to LT sided heart failure

* **BIG DEAL because EVERYTHING below becomes necrotic > FULL DEATH of HEART

Question 16

MI + EKG: what type of EKG is gold standard for MI?

Answer 16

****12 LEAD EKG is ONLY EKG used to determine MI

Question 17

EKG zones

Answer 17

EKG reads will fall into THREE-ZONES; these zones show what the heart is OR isn’t doing & gives some insight as to what is going on + how severe.

• Zone of Ischemia
• Zone of Injury
• Zone of Necrosis

Question 18

ZONE OF ISCHEMIA

Answer 18

-ST segment depression (because of lack of oxygen)
»electrical disturbance
***WORK TO RESTORE BLOODFLOW QUICKLY; there is the ability for this area to return to normal without becoming necrotic
-needs follow up but isn’t sudden death.

**ST segment depression MUST be present for AT least 1mm LOW on EKG strip

Question 19

ZONE OF INJURY

Answer 19

(cells are NOT fully repolarizing because of the lack of oxygen)

• INTERVENTIONS NEED TO OCCUR
• **TREAT EFFECTIVELY & QUICKLY to prevent permanent damage!!!

**ST segment elevation must be present in TWO LEADS; for AT LEAST 1mm HIGH on EKG strip

Question 20

ZONE OF NECROSIS

Answer 20

(ST elevation = most important part of this on EKG)
-this is where scarring starts to occur; scarring can interfere with muscle function (scarring interferes with ability to conduct electrical impulses)

***Scarring > remodeling; remodeling = increased risk of death

Question 21

MI zones severity: least > most

Answer 21

ZONE OF ISCHEMIA > ZONE OF INJURY >

ZONE OF NECROSIS

Question 22

What do you want to prevent in an MI, which can ultimately be life saving!?

Answer 22

***preventing REMODELING is very important and can safe your patients life!

Question 23

STEMI vs NSTEMI

Answer 23

STEMI = ST(segment) ELEVATED MI
^^^^^^**EMERGENT

NSTEMI = NON ST(segment) ELEVATED MI
^^^^^^***NON-EMERGENT but requires follow-up!

Question 24

STEMI (ST(segment) ELEVATED MI)

Answer 24

***MUST be determined by 12 lead EKG + MUST show up on 2 of the leads @ 1mm HIGH

> > Intervention needed IMMEDIATELY; could mean coronary artery is occluded > heart muscle death likely

Question 25

NSTEMI (NON ST(segment) ELEVATED MI)

Answer 25

-likely from an INCOMPLETE coronary artery occlusion **chest pain likely present BUT oxygen + nutrients are still being supplied -needs treatment/attention BUT is not emergent >>>no Q wave will be present

Question 26

Main goals for a patient with possible/likely/identified MI

Answer 26

- minimize damage - preserve function - reperfusion of myocardial muscles - prevention of complications

Question 27

How can I prioritize my care as a nurse to achieve these goals?

Answer 27

``` #1: Assess ABC's: airway, breathing, circulation #2: Position for optimal gas exchange + admin oxygen #3: Obtain vital signs #4: 12 Lead EKG #5: IV access #6: Assess pain using (PQRST) #7a: Admin NITRO #7b: Admin aspirin #8: Admin morphine #9: Continuous EKG monitoring #10: Obtain bloodwork #11: Chest X-Ray #12: Admin STATINS ```

Question 28

#1: ABC's

Answer 28

Airway Breathing Circulation

Question 29

#2: Position + Oxygen admin

Answer 29

Ensure your patient is upright Admin oxygen as/if needed **O2 goal with MI is 93% or greater

Question 30

#3: Obtain vital signs

Answer 30

Frequently assess vital signs + compare to previously obtained or baseline vital signs to determine any significate changes!

Question 31

#4: 12 Lead EKG

Answer 31

MI CANNOT be dx'd without a 12 lead EKG; this is gold standard for MI dx!

Question 32

#5: IV access

Answer 32

you may/may not need more than one IV access site: you might need to give medications and or fluids and they may not all be compatible with each other!

Question 33

#6: Assess PAIN w/ PQRST

Answer 33

P: precipitating event: what lead up to the MI/chest pain; what were you doing? Q: quality of pain: how bad is it, what kind of pain is it? R: radiation of pain: is the pain radiating to other locations? S: severity of pain: how severe is the pain, what level 0-10, etc. T: timing: how long has the pain been present?

Question 34

#7a: Administer NITRO

Answer 34

NITRO can be administered Q5minutes for 15 minutes; nitro will TANK B/P, DO NOT give if patient is HYPOtensive. * *Assess allergies before admin * **Assess previous admin before admin: was patient brought in by ambulance and given by EMT? these need to be determined before administration!

Question 35

#7b: Administer Aspirin

Answer 35

Admin Aspirin after NITRO, if needed; normally 325mg chewable tablet

Question 36

#8: Administer Morphine (IV)

Answer 36

IF nitro doesn't relieve the pain, or achieve desired effect, administer morphine BUT only AFTER NITRO; same considerations for Morphine because morphine can TANK B/P and cause HYPOtension; what is B/P?

Question 37

#9: Continuous EKG monitoring

Answer 37

patients with MI/possible MI are at higher risk for other dysrhythmias **A-FIB; they need to be attached to continuous monitoring to ensure these are addressed if happens

Question 38

#10: Obtain bloodwork

Answer 38

Bloodwork needs to be obtained to see what is going on: - electrolytes - CBC - cardiac markers

Question 39

#11: Chest X-ray

Answer 39

is there any cardiac enlargement? is there anything else on this x-ray that makes you think its NOT an MI? etc.

Question 40

#12: Administer STATINS

Answer 40

Administer HIGH DOSE STATINS

Question 41

What S/S should I look for in my patient + what S/S should I educate my patient to look for?

Answer 41

***SUDDEN ONSET CHEST PAIN that: -NOT relieved w/ rest OR medications -20 minutes or longer -the chest pain feels CRUSHING (like elephant sitting on chest, etc.) -neck/jaw, epigastric, sternal or back pain **SOB **nausea **anxiety **cool, pale, moist skin (grey in appearance) **indigestion (not relieved with antiacids) ****INCREASED RR + HR (this is compensatory) ^^^ trying to blow off more CO2 to get more O2

Question 42

What is so significate about Diabetes and MIs?

Answer 42

**diabetics are KNOWN to have SILENT MIs because of their increased neuropathy (they cannot feel it because of this)

Question 43

Diabetics and MIs

Answer 43

diabetics NEED: -continuous monitoring: this helps determine any changes that are occurring since your patient may or may not feel these changes; this also helps know what/when medications are necessary

Question 44

What else can you do for diabetics regarding MIs or possible MIs?

Answer 44

- offer SUPPORT - EDUCATE the patient on what to look for * *prepare for POSSIBLE emergency: crash cart, intubation kit, etc.

Question 45

What labs/diagnostics are important for determining an MI?

Answer 45

``` **Troponin **Lipid Profile **Chest X-Ray The GOLD STANDARD lab for MI is: TROPONIN (T)/(I) TROPONIN T: 0.1+ = POSITIVE for MI TROPONIN I: 0.04+ = POSITIVE for MI ```

Question 46

What is important to remember about TROPONIN?

Answer 46

TROPONIN elevation occurs 4-6 hours POST-INJURY and can last up to 10-14 days!

Question 47

What does treatment for NSTEMI patients look like?

Answer 47

#1: start on antiplatelet drugs (aspirin/heparin), to prevent clot formation ^^^^increases bleed time; so monitor) #2: start on beta-blockers ^^^^decreases workload on heart #3: start ACE inhibitors/ARBs ^^^^decreases workload on heart + decreases remodeling #4: start/administer NITRO (vasodilates) ^^^^reduces workload AND pain

Question 48

What type of treatments are performed in the operating room for MI patients?

Answer 48

- coronary artery bypass graft | - off-pump coronary artery graft

Question 49

What physiological changes can occur after an MI?

Answer 49

- leucocytes start coming to the heart and start remodeling! (DO NOT WANT) - necrotic muscle = THIN MUSCLE; which leaves the patient at risk for ventricular aneurysms!!!!