CMPP -- Ischemic Heart Disease 2: Unstable Angina

Stable angina

chest pain that is predictable and reproducible that is associated with known exertion/stress that is relieved within 5-10 minutes with rest and/or nitroglycerine

occurs with minimal exertion or at rest; is new onset angina; is a worsening change in a previously stable angina patient in terms of frequency or duration of attacks; is resistant to previous effective treatments; is provoked with decreasing levels of exertion or stress

unstable angina is angina with at least one of what characteristics?

Non ST-segment elevation MI

clinical picture of unstable angina with physical evidence of myocardial necrosis via elevated cardiac biomarkers (troponin) but a lack of any ST segment elevation on the EKG

may not have total occlusion of a coronary artery; partial sparing of infarcted myocardium thanks to collateral circulation

why do NSTEMIs occur?

decreased o2 supply or increased myocardial demand (plaque rupture and non-occlusive thrombus formation, dynamic obstruction (coronary vessel spasm), progressive mechanical obstruction (advancing atherosclerosis), secondary to increased demand or decreased supply (tachycardia or anemia)

what are some phyiological causes of an NSTEMI?

multiple sites at risk on angiography

UA/NSTEMI patients typically have...

substernal or precordial

classic placement of pain for pts with CAD

discomfort, squeezing, pressure, tightness, fullness, burning, heaviness

classic quality of pain for pts with CAD

neck, jaw, shoulders, down the left arm

classic radiation of pain for pts with CAD

with exertion, heavy meals, cold exposure, stress

classic onset of pain for pts with CAD

with rest (maybe)

classic palliative measures for pain for pts with CAD

2-20 minutes

classic timing of pain for pts with CAD

dyspnea, N/V, diaphoresis, weakness, palpitations, dizziness, fatigue, anxiety

classic associated symptoms for pts with CAD

anginal equivalents

Signs and symptoms other than typical chest pain, such as shortness of breath, produced by myocardial ischemia; for any pt with known CAD who presents with equivalent symptoms; must assume it is the same as chest pain and work up that pt appropriately

dyspnea, N/V, diaphoresis, indigestion, syncope

anginal equivalents

dyspnea, weakness, altered mental status/LOC

common symptoms of MI in the elderly

dyspnea, N/V, fatigue

common symptoms of MI in diabetic pts

dyspnea, indigestion, weakness, diaphoresis, anxiety

common symptoms of MI in women

diaphoretic, pale, cool skin, sinus tachycardia, basilar rates (HF), hypotension

physical exam findings on a pt that is having an MI

subendocaridal ischemia; acutely/chronically

ST segment depression usually represents _________, and it can be _______ or _______

NSTEMI, preceding a STEMI, reciprocal change (mirror image of something going on on other side), posterior MI

causes of ST segment depression

serial EKGs

just because it isn't showing STEMI now, doesn't mean it won't show STEMI later, so, you should always order...

ischemia

inverted T-waves indicate...

J point

Point where the QRS complex and ST segment meet

Creatine Phosphokinase, CK - MB, troponin, myoglobin

specific cardiac biomarkers tested for in one with an NSTEMI

4-8 hours

Creatine Phosphokinase levels increase within ____ of infarction

12-24 hours

Creatine Phosphokinase levels peak within ________.

3-4 days

Creatine Phosphokinase levels stay elevated for....

no, it can also be found in skeletal muscle, brain, kidney, lung, and GI tissue; increased levels can also indicate skeletal muscle damage

is CK specific?

4-10 hours

Creatine Phosphokinase-MB levels rise within _____ of infarction

12-24 hours

Creatine Phosphokinase-MB levels peak within ________ of infarction

2 days

Creatine Phosphokinase-MB levels stay elevated for about ____ after infarction

yes, but still small amount exists in skeletal muscle

is Creatine Phosphokinase-MB specific for the myocardium?

Myoglobin

small protein found in ALL muscle tissue

1-2 hours

Myoglobin levels rise within ______ of infarction

5-7 hours

Myoglobin levels peak within ______ of infarction

24 hours

Myoglobin levels stay elevated for about ______ after infarction

no, and there is no way to specific if elevation is from skeletal or cardiac muscle

are myoglobin levels specific?

Troponin I

the most specific biomarker for the heart, best sensitivity and specificity

6 hours

Troponin levels rise within ____ of infarction

12-18 hours

Troponin levels peak within _______ of infarction

7-10 days

Troponin levels stay elevated _____ after infarction

positive on 1st measurement, negative on second

what constitutes a false positive for troponin levels?

pericarditis, LVH, CHF, non-penetrating/penetrating cardiac trauma, arrhythmias, PE, sepsis, renal insufficiency

what are some other reasons that troponin can be elevated other than MI?

High Sensitivity Troponin Assay

more sensitive test that catches MIs earlier; decreases wait time for diagnosis and decreases need for potentially unnecessary testing and admission

mortality

there is a direct relationship between degree of troponin and...

history of stable angina, established CAD by angiography, prior MI, CHF, new EKG changes, elevated biomarkers

factors for a high likelihood CAD

admitted to the hospital for observation

any patient with significant history significant for heart issues and are suspected to be having an MI should be...

Thrombolysis in Myocardial Infarction (TIMI)

For patients with history of unstable angina (UA) and NSTEMI; a simple prognostication scheme that categorizes a patient's risk of death and ischemic events and provides a basis for therapeutic decision making; predicts a 14 day outcome of UA/NSTEMI pts

older than 65, 3+ CAD risk factors, documented CAD on angio, development of UA/STEMI on ASA, 2 angina episodes in the last 24 hours, ST deviation of greater than 0.5 mm, 1 elevated cardiac biomarker

factors measured in TIMI

MI, need for catheterization, and death

the higher the TIMI number, higher risk of...

HEART score

assessment that predicts for ACS; better predictive capacity than TIMI

history, electrocardiography, age, risk factors, troponin

what does "HEART" in HEART score stand for?

MONA (most of which can be done in the office while waiting for EMS to transport a patient to the ER)

treatment approach for UA/NSTEMI

Morphine (for pain relief), Oxygen, Nitroglycerine, Aspirin

what does MONA stand for?

Morpine

opioid analgesic that also has some anxiolytic properties; CNS depressant

refractory to nitroglycerine

Morphine is used for pts with chest pain that is...

lessen oxygen consumption and myocardial work

Morphine will allow for pain and anxiety relief, that should...

hypotension, histamine release/itching (increased capillary permeability)

side effects of morphine

binds to CNS opioid receptors

morphine MOA

any patient with chest pain that is not relieved with nitro

Morphine is best for...

detrimental (causes release of free radicals --> oxygen toxicity)

recent studies have shown that too much oxygen can be...

only give to pts who are dyspneic or who have SPO2 <94%

recommendation for oxygen administration for those having UA/NSTEMI

2-4 LPM via Nasal Cannula

typical administration of oxygen

vasodilator

nitroglycerine MOA

Q5 minutes x 3

frequency of nitroglycerine administration

hypotension, headache

side effects of nitroglycerine

inhibits platelet cyclooxyrgenase and reduces thromboxane A2 (tells platelets not to stick to each other)

aspirin MOA

324 mg (FOUR 81 mg tabs) CHEWED AND SWALLOWED

dose and route of ASA

bleeding, dyspepsia (need to know what they took prehospital, looking to total out at 324 mg)

side effects of ASA

ALL patients with suspected or known CAD presenting with chest pain

aspirin is best for...