Acute Coronary Syndrome

Question 1

Coronary Artery Disease

Answer 1

Accounts for most CV deaths in the US
▪ Mostly caused by atherosclerosis
▪ Progressive disease
▪ Risk factors: nonmodifiable, modifiable, contributing modifiable

Question 2

MI Classification

Answer 2

Affected area of the heart: anterior, lateral, inferior, or
posterior
▪ EKG changes produced: STEMI vs NSTEMI
▪ Time-frame within progression of MI: acute, evolving, old

Question 3

What’s the culprit for most MIs?

Answer 3

blocked coronary artery

Question 4

Ischemia, injury, and infarction

Answer 4

imbalance
between myocardial blood supply and oxygen
demand

Question 5

Unstable angina

Answer 5

Partially occluded by a thrombus, Negative cardiac enzymes
New in onset, or chronic stable angina that increases in frequency, duration, or severity occurs at rest or minimal
exertion pain refractory to NTG

Question 6

NSTEMI

Answer 6

Partially occluded by a thrombus
Positive cardiac enzymes

Question 7

STEMI

Answer 7

Totally
occluded by
a thrombus
Positive
cardiac
enzymes

Question 8

PQRST

Answer 8

Precipitating
events
Quality of pain
Radiation of pain
Severity of pain
Timing

Question 9

Myocardial
infarction (MI)

Answer 9

Irreversible myocardial cell deathcontractile function of the heart
stops in the necrotic area(s)
▪ Cell death occurs after
approximately 20 minutes of
ischemia
▪ Thrombus formation causes 80-90%
of all acute MIs (other causes?)
▪ Role of collateral circulation

Question 10

Definition of NSTEMI

Answer 10

“Ischemic ST-segment depression of 0.5 mm (0.5 mV) or
greater -OR- Dynamic T wave inversion with pain or
discomfort / Transient ST elevation of 0.5 mm or greater
for less than 20 minutes.

Question 11

Definition of STEMI

Answer 11

New ST segment elevation at the J point in at least two
contiguous leads of ≥ 2 mm (0.2 mV) in men or ≥ 1.5
mm (0.15 mV) in women in leads V2-V3 and/or of ≥ 1 mm
(0.1 mV) in other contiguous chest leads or the limb leads
-OR- new or presumed new left bundle branch block.”

Question 12

Clinical Manifestations of MI: PAIN

Answer 12

severe immobilizing chest pain not relieved by
rest, position change, or nitrate administration
▪
“elephant on my chest”, “pressure”, “tightness”,
“crushing”
▪ Substernal, retrosternal, epigastric; may radiate
to neck, jaw, arms or back
▪ May occur at rest, with exertion, asleep, or awake

Question 13

Clinical Manifestations of MI

Answer 13

Skin: ashen, clammy, & cool to touch, diaphoretic
▪ Cardiovascular: BP & HR increased at first. Later,
decreased BP with decreased cardiac output. May have
distant heart sounds, S3, S4, or loud holosystolic
murmur
▪ GI: N & V
▪ Fever: low grade within first 24 hrs up to 1 week

Question 14

Clinical Manifestations of MI- atypical

Answer 14

Women: dizziness, SOB,
unusual tiredness
Patients with diabetes
mellitus: asymptomatic or
atypical (dyspnea), “silent
MI”
Older patient: change in
mental status, dizziness, SOB,
or a arrhythmia

Question 15

Ignoring signs and symptoms

Answer 15

Half of the patients who die of ACS do so before
reaching the hospital.
▪ Ventricular fibrillation(VF) or pulseless ventricular
tachycardia is precipitating rhythm
▪ VF likely to develop in first 4 hours after onset of
symptoms
Education: seek help early and don’t drive yourself, call
91

Question 16

ACS Diagnostic Studies -1

Answer 16

12-lead ECG (Obtain within 10 min on arrival to ED)
* Distinguish between unstable angina (UA), non-ST
segment elevation myocardial infarction (NSTEMI), ST
elevation myocardial infarction (STEMI)
* Serial
* If available, will compare to old ECG

Question 17

ACS Diagnostic Studies (2)

Answer 17

Serum Cardiac Markers
* Cardiac-specific troponin: Troponin T and Troponin I:
serial sampling q6-8 hr x 3 (watch trend)
* CK-MB isoenzyme (if a troponin test is unavailable,
considered an acceptable substitution)
* Myoglobin: one of the first to appear, lacks cardiac
specificity

Question 18

ACS Diagnostic Studies (3)

Answer 18

Coronary Angiography (cardiac cath)– evaluate patency
of coronary arteries and collateral circulation
- STEMI patients
- high-risk patients with UA or NSTEMI, depending on risk
stratification
Other Measures
* Exercise or pharmacologic stress testing (after 3 negative
troponins)
* echocardiogram

Question 19

Risk stratification

Answer 19

TIMI Risk Score: estimates mortality with UA, NSTEMI, STEMI
UA/NSTEMI
STEMI
 GRACE ACS estimates admission-6month mortality for
patients with ACS
▪ HEART: predicts 6 week risk of major adverse cardiac event
▪ EBP: CRP level and coronary artery calcium scoring to
improve risk classification

Question 20

Healing Process after MI

Answer 20

Inflammatory process:
Leukocytes, cardiac enzymes released (within 24
hours)
Macrophages (by the fourth day)
Collagen matrix (10-14 days)
Scar tissue (by 6 weeks)
Ventricular remodeling: changes in the infarcted
myocardium causes changes in the unaffected
myocardium

Question 21

MI Complications - arrhythmias

Answer 21

Arrhythmias
* Present in 80-90% 0f patients
* Most common cause of death in prehospital setting
(get AED!)
* Ischemia, electrolyte imbalance, SNS stimulate can
affect the myocardial cell’s sensitivity to nerve
impulses

Question 22

MI Complications-III

Answer 22

~ Cardiogenic shock:
shock state resulting from impairment or failure of the
myocardium.
~ anterior MI at greatest risk
May require intra-aortic balloon pump (IABP)
counterpulsation

Question 23

IV. MI Complications-
Acute Pericarditis

Answer 23

Acute Pericarditis
* occurs 2-3 days after MI
* sharp, stabbing chest pain,
usually comes on quickly
* The pain tends to ease when patient
sits up and leans forward. Lying
down and deep breathing worsens
it.
* Friction rub, fever
Treatment: NSAIDs, ASA, or
corticosteroids

Question 24

IV. MI Complictions-
Dressler Syndrome

Answer 24

Dressler Syndrome “post
myocardial infarction
syndrome”
▪ develops 4-6 wks. after MI
▪ pericarditis with fever,
pleuritic pain, and effusion
▪ elevated WBC, ESR
▪ elevated ST segments
throughout all 12 leads
Treatment: NSAIDS,
corticosteroids

Question 25

V. Rare MI Complications

Answer 25

Ventricular Aneurysm ~
Papillary muscle dysfunction

Question 26

Collaborative Care ACS

Answer 26

Ambulance/ED
- 12 lead ECG and start continuous ECG monitoring
- O2 by NC to keep oxygen sat>94%
- monitor vital signs, pulse oximetry
- IV access
- chewable aspirin, SL NTG, morphine sulfate for pain
unrelieved by NTG
- bedrest and limit activity for 12-24 hrs

Question 27

Collaborative care for patient with
unstable angina/NSTEMI

Answer 27

Admit to monitored bed or chest pain unit
Acute intensive drug therapy: nitroglycerin, antiplatelet
& anticoagulation therapy
Possible PCI (depending on risk stratification)

Question 28

Collaborative care for patient with STEMI
and positive cardiac markers

Answer 28

Reperfusion therapy
a.) mechanical reperfusion-PCI if available (cath lab)
b.) pharmacologic reperfusion-thrombolytic therapy
(ED/ICU)
c.) surgical revascularization- CABG (OR)
Concurrent drug therapy (antiplatelet & anticoagulant
therapy)

Question 29

Percutaneous Coronary Intervention
(PCI)

Answer 29

Emergent PCI
“Time is muscle” door-to-balloon inflation (PCI) goal = 90
minutes
First line of treatment for confirmed STEMI
Advantages
Nursing care
Complications

Question 30

Thrombolytic therapy

Answer 30

Thrombolytic therapy (also called fibrinolytic therapy)
“Time is muscle” door-to-needle goal (fibrinolysis) = 30 minutes
(no later than 6-12 hours after onset of symptoms)
Used in facilities that do not have interventional cardiac
catheterization lab or too far away to transfer
Given IV – lysis of thrombus
Inclusion criteria
Absolute/relative contraindications
Nursing care
Complications

Question 31

Collaborative Care: ACS: Pharmacology
Therapy

Answer 31

dual antiplatelet therapy (aspirin and clopidogrel)
systemic anticoagulation
nitroglycerin IV
morphine sulfate
B-adrenergic blockers
ACE inhibitors
antidysrhythmic drugs
lipid-lowering drugs
stool softeners

Question 32

Ongoing Nursing Considerations

Answer 32

▪Concentrated repeated pain assessment
▪Physiological monitoring
▪Alleviation of stress & anxiety
▪Depression is common after having an MI and CABG
▪Gradually increase activity

Question 33

Discharge Educational Needs

Answer 33

Patient & Family teaching
* Preventative: what to do if they have chest pain
* Medication (what they are, schedule, why they help); ie.NTG SL
* Diet/Nutrition: Low sat fat, low sodium, fruits and veggies: foods
rich in folic acid such as green leafy vegetables, fruits; vitamins w/
folic acid, B complex vitamins (lowers blood homocysteine levels)
* C & DB (IS, splinting with pillow)
* Incisional care
* Exercise/Cardiac rehab
* Smoking Cessation
* Follow up w/ PCP