Myocardial Infarction/ECG Flashcards
What are the limb leads?
I, II, III, AVR, AVL, AVF
In what plane do the limb leads show depolarization?
Coronal plane
What are the precordial leads?
V1 - V6
In what plane do the precordial leads show deplorization?
Transverse (horizontal) plane
What is meant by the cardiac axis?
Overall depolarization direction of the heart in the coronal plane
What leads do you look at to determine the cardiac axis?
I and AVF
If the QRS complex is deflected upward (+), where is the depolarization moving?
Towards lead
If the QRS complex is deflected downward (-), where is the depolarization moving?
Away from the lead
What is the normal axis?
0-90 degrees
How do you plot the cardiac axis?
Take the number of boxes the leads I and AVF QRS complexes move (NET) and graph against each other.
Normal axis
(+) Lead I and (+) Lead AVF
Left axis
(+) Lead I and (-) Lead AVF
(+) lead I and (-) lead AVF
Left axis
Right axis
(-) Lead I and (+) Lead AVF
(-) lead I and (+) lead AVF
Right axis
What are the main symptoms of coronary artery disease/STEMI?
Chest discomfort that radiates to neck, jaw, shoulder, left arm
Sweating, nausea, vomiting, shortness of breath
STEMI means the coronary A. is?
Occluded
What are the 3 zones of infarction?
- Ischemia (compromised)
- Injury (dying tissue)
- Infarction (dead tissue)
With ischemia, what EKG change will be registered?
T wave changes
With injury, what EKG change will be registered?
ST segment shifts up or down
With infarction, what EKG change will be registered?
Q wave
Main cardiac biomarker of necrosis?
Troponin I or T
What can cause a false positive cTnT (troponin)?
Renal failure
How soon after an acute MI is Troponin detectable?
1-4 hours
NSTEMI has ____ ST elevation
NO
NSTEMI, changes in troponin levels?
Increase!