Acute myocardial infarction (PEARLS): Non-ST-Segment Elevation MI, ST-Segment Elevation Myocardial Infarction (Smarty PANCE)
Q waves and ST elevation in leads *I, AVL, and V2 to V6*
Anterior wall infarction
Appears at 4-6 hours, peaks at 12-24 hours and *lasts for 3-4 days*
CK/CK-MB
The _____________ supplies the inferior part of the heart
RCA
the __________________supplies the right ventricular part of the heart
RCA
You will have a ST _______________ in a transmural (epicardial) injury
elevation
The ______________supplies the posterior part of the heart
left circumflex artery
There are ___________sinuses but only ________ coronary arteries
3, 2
Initial treatment of NSTEMI?
All patients presenting with symptoms of Acute Coronary Syndrome will get standard (MONA) ● Morphine (IV if pain not relieved by NTG) ● Oxygen (4L/min) ● Nitroglycerine (sublingual) - 0.4 mg every five minutes for a total of three doses ● Aspirin (160-325 mg) chewed
ECG changes of Non-ST-segment elevation MI?
ECG changes such as ST-segment depression, T-wave inversion, or both may be present (no ST elevation or Q waves)
*Anterior wall Q wave infarctions* can be identified by changes in _________and ________ . ● Significant ST elevation ● V leads will show changes as well
I, aVL
*Inferior wall Q wave infarctions* can be identified by changes in ________, _________, and _____________ .
II, III, aVF
Name the three inferior leads
II, III, and aVF
Q waves and ST elevation in leads *II, III, and AVF*
Inferior wall infarction
ST elevations in leads *I, AVL, and V5 to V6*
Lateral wall infarction
A blockage of which artery causes an anterior wall MI?
Left anterior descending (LAD)
A blockage of which artery causes lateral wall MI?
Left circumflex artery
What is Non-ST-segment elevation MI?
Non-ST-segment elevation MI (NSTEMI, subendocardial MI) is myocardial necrosis (evidenced by cardiac markers in blood; troponin I or troponin T and CK will be elevated) without acute ST-segment elevation or Q waves
NSTEMI vs. unstable angina?
Only difference is elevated cardiac enzymes in NSTEMI. Unstable angina and NSTEMI differ primarily in whether the ischemia is severe enough to cause sufficient myocardial damage to release detectable quantities of a marker of myocardial injury (troponins)
GOLD STANDARD treatment for STEMI best if within 3 hours (90 minutes) of sx onset
PCI (Percutaneous Coronary Intervention)
What is the difference in early medical regimen of NSTEMI, unstable angina, and STEMI?
Patients with unstable angina (UA) or acute non-ST elevation myocardial infarction (NSTEMI) should be treated with an early medical regimen similar to that used in an acute ST elevation MI (STEMI) with one exception: There is no evidence of benefit (and possible harm) from fibrinolysis
________________elevation is required for STEMI. Within 2 minutes to hours.
ST segment
Substernal chest pain radiating to the neck and arm with ST-segment elevations > 1mm in > 2 contiguous leads on ECG and evidence of myocardial necrosis (cardiac markers in blood; troponin I or troponin T and elevated CK). What's the diagnosis?
ST-Segment Elevation Myocardial Infarction (STEMI)
_______________alterations is often the *first sign of myocardial injury*. Not specific.
T wave
Appears at 2-4 hours, peaks 12-24 hours and *lasts for 7-10 days*
Troponin
Troponins increase in ______ hours and peak at ______ hours and return to normal after _____ days.
Troponin are the most sensitive and specific ● Increase: 3-5 hours ● Peak: 24-48 hours ● Normal: 5 to 14 days
Which EKG leads are used to diagnose an anterolateral MI?
V5 and V6
You will have a ST ___________________ in a subendocardial injury
depression
Myocardial _______________ is an area of non-functioning and possibly dead cardiac myocytes
infarction
If you have a posterior MI, the changes are ________________ ● Look at *V1-V3 and observe deep R wave and ST segment depression*
inverted
Myocardial ___________ is a state of reduced oxygen supply or increased demand for an area of the heart
ischemia
T symmetric wave inversion is a sign of myocardial ischemia in the ________________ layer
subendocardial
The _____________ layer of the heart is most susceptible to ischemia
subendocardial
*Q wave changes* are often associated with ____________STEMI. ● Evolve over the first day of injury or so.
transmural
When ischemia is _______________, the T waves may become *hyperacute* (tall and peaked)
transmural
CK-MB increases in ____ hours, peaks at _____ hours, and returns to normal at _____ hours
● Increases: 4 to 8 hours ● Peak: 24 hours ● Normal: 2-3 days
Absolute contraindications for fibrinolytic use in STEMI
● Prior intracranial hemorrhage (ICH) ● Known structural cerebral vascular lesion. ● Known malignant intracranial neoplasm. ● Ischemic stroke within 3 months. ● Suspected aortic dissection. ● Active bleeding or bleeding diathesis (excluding menses)
STEMI vs. NSTEMI vs. unstable angina
● STEMI = ST elevation + cardiac markers ● NSTEMI = ST depression, T-wave inversions (no ST elevations) + cardiac markers ● Unstable angina = +/- ST depression, T-wave inversions (no ST elevations) & NO cardiac markers
NSTEMI vs STEMI?
● STEMI: transmural (involves the full thickness of the myocardium) ● NSTEMI: subendocardial (deep layer of left ventricular muscle)