Acute Coronary Syndrome

Question 1

types of angina

Answer 1

–Printzmetal’s Variant Angina
–Chronic Stable Angina
–Unstable Angina

Question 2

Printzmetal’s Variant Angina

Answer 2

–vasospasm
–supply ischemia
–not due to atherosclerosis

Question 3

Unstable Angina

Answer 3

–thrombus
–supply ischemia
–due to atherosclerosis

Question 4

causes of variant/vasospastic angina (Prinzmetal angina)

Answer 4

–coronary artery spasm
–endothelial dysfunction

Question 5

characteristics of variant/vasospastic angina

Answer 5

–CAD may or may not be present
–onset: rest, minimal exertion, night
–elevated ST segment

Question 6

characteristics of unstable plaque causing ACS

Answer 6

–large lipid core
–active inflammation
–smooth muscle cell proliferation into intima
–thin fibrous cap

Question 7

specifics of unstable angina

Answer 7

–chest pain occurring for the first time
–chest pain more severe than usual with chronic angina
–new regions of the heart are undergoing myocardial ischemia
–emergency situation

Question 8

why is there no infarction with unstable angina?

Answer 8

–occlusion is partial
–thrombus dissolves

Question 9

EKG changes with unstable angina

Answer 9

might see ischemic changes, typically transient

Question 10

are cardiac enzymes elevated with unstable angina?

Answer 10

no

Question 11

theory of plaque rupture

Answer 11

–increased SNS activity
–plaque rupture
–thrombus formation

Question 12

components of increased SNS activity leading to plaque rupture

Answer 12

–increased BP, HR, and force of contraction
–increased force of coronary artery blood flow
–increased force exerted against injured endothelium

Question 13

components of plaque rupture leading to thrombus formation

Answer 13

–platelets adhere to ruptured plaque
–release substances that (1) attract more platelets and (2) contribute to vasospasm

Question 14

contributing factors to increased SNS activity leading to plaque rupture

Answer 14

–psychological stress
–exercise
–circadian rhythms

Question 15

signs of MI in men

Answer 15

–discomfort or tingling in arms, back, shoulder, or jaw
–chest pain
–SOB

Question 16

signs of MI in women

Answer 16

–sudden dizziness
–heartburn-like feeling
–cold sweat
–unusual tiredness
–nausea or vomiting

Question 17

general s/s of MI

Answer 17

–diaphoresis
–dyspnea
–extreme anxiety
–Levine’s sign (fist to chest)
–pallor
–retrosternal crushing chest pain that radiates to shoulder, arm, jaw, or back
–weak pulses

Question 18

what is an acute MI?

Answer 18

ruptured plaque + thrombus

Question 19

why do infarctions occur?

Answer 19

–blood flow disruption is prolonged
OR
–blood flow disruption is total

Question 20

EKG changes with MI?

Answer 20

yes

Question 21

cardiac enzyme elevation with MI?

Answer 21

yes

Question 22

acute MI

Answer 22

acute coronary syndrome with prolonged ischemia without recovery

Question 23

importance of ATP with ischemia/infarction

Answer 23

–decreased O2 = decreased ATP
–decreased ATP = decreased contractility

Question 24

when does irreversible injury to cardiac muscle occur?

Answer 24

within 30 min to 4 hours

Question 25

when does tissue necrosis begin?

Answer 25

by 4 hours

Question 26

when is necrotic tissue cleared away?

Answer 26

by 1-2 weeks

Question 27

when does tough fibrous scar tissue replace necrotic tissue?

Answer 27

by 6 weeks

Question 28

three zones of tissue damage

Answer 28

--ischemia --injury --infarction

Question 29

infarction

Answer 29

--necrosis --MI, dead cells --beyond hope of recovery but can stop from increasing

Question 30

injury

Answer 30

--some recovery possible --can still perfuse it and restore it to become viable --not dead yet

Question 31

ischemia

Answer 31

full recovery possible

Question 32

how to prevent extension of infract?

Answer 32

--increase oxygen --decrease the demand on the heart

Question 33

what influences the extent of damage in a MI?

Answer 33

--location or level of occlusion in the coronary artery --length of time that the coronary artery has been occluded --heart's availability of collateral circulation

Question 34

ST segment in STEMI v. NSTEMI

Answer 34

STEMI = elevated NSTEMI = depression or normal

Question 35

QRS in STEMI v. NSTEMI

Answer 35

STEMI = usually pathologic (wide), develops over hours NSTEMI = normal

Question 36

T wave in STEMI v. NSTEMI

Answer 36

STEMI = peaked, then inverted NSTEMI = inverted

Question 37

Trop in STEMI v. NSTEMI

Answer 37

STEMI = elevated NSTEMI = elevated

Question 38

size of infarct in STEMI v. NSTEMI

Answer 38

STEMI = larger NSTEMI = smaller

Question 39

outcomes of STEMI v. NSTEMI

Answer 39

STEMI = poor NSTEMI = better

Question 40

left anterior descending artery

Answer 40

--supplies the left ventricle --most commonly involved in MIs

Question 41

three main arteries that supply the heart with blood

Answer 41

--right coronary artery --left circumflex artery --left anterior descending artery

Question 42

diagnostics for acute MIs

Answer 42

--serum cholesterol, LDL, HDL, triglycerides --ECG --serum electrolytes --serum glucose --CRP --serum homocysteine --cardiac enzymes --CXR --CT scan --cardiac angiogram and cardiac cath --ECHO

Question 43

initial treatment of acute MIs

Answer 43

--oxygen --morphine --ASA --nitro --beta blocker --thrombolytic agent

Question 44

when are thrombolytic agents used?

Answer 44

within 4-6 hours of beginning of MI

Question 45

reason for giving oxygen with MIs

Answer 45

increase O2 delivery to ischemic myocardium

Question 46

reason for giving ASA with MIs

Answer 46

suppresses platelet aggregation --decreases mortality --chew first dose

Question 47

reason for giving morphine with MIs

Answer 47

decreases pain reduces preload and afterload --helps preserve ischemic tissue

Question 48

reason for giving beta blocker

Answer 48

reduce HR and contractility --reduces pain, infarct size, and mortality

Question 49

reason for giving nitro

Answer 49

reduces preload and afterload limits infarct size --does not reduce mortality

Question 50

example of fibrinolytic therapy

Answer 50

Alteplase (tPA)

Question 51

MOA of alteplase (tPA)

Answer 51

dissolves clot by converting plasminogen into plasmin

Question 52

advantages to alteplase (tPA)

Answer 52

most effective

Question 53

disadvantages to alteplase (tPA)

Answer 53

works best within 30-70 minutes

Question 54

main adverse effect of alteplase (tPA)

Answer 54

bleeding

Question 55

what is tPA always given with?

Answer 55

heparin and antiplatelet therapy

Question 56

side effects of nitro

Answer 56

--hypotension --headache --flushing

Question 57

what shouldn't be given with nitro?

Answer 57

sildenafil (Viagra) --> severe hypotension

Question 58

interventions for reperfusion

Answer 58

stent/balloon angioplasty

Question 59

myocardial stunning

Answer 59

contributes to injury through rapid restoration of blood flow to the myocardium

Question 60

what is reperfusion injury caused by?

Answer 60

oxidized free radicals generated by WBCs and the cellular response to restored blood flow

Question 61

who suffers silent, asymptomatic MIs?

Answer 61

--diabetics --older than age 65

Question 62

major causes of MI death

Answer 62

--hesitation --delayed request for emergency care

Question 63

drug therapy post-MI

Answer 63

--ASA --beta blocker --ACE inhibitor --statin