EKG Flashcards
What is Coronary Artery Disease
-plaque builds up in the coronary arteries which causes narrowing/blockages which decrease blood flow to the heart
-the disease typically cycles in and out of clinically defined phases: Asymptomatic Stable Angina Accelerating Angina Acute Coronary Syndrome
What is Asymptomatic coronary artery disease?
-plaque is present but not significant
What is Stable Angina
- predictable symptom provocation
- know disease
- collateral circulation usually present-Example: Ask pt “are you able to go up 2 flights of stairs”- they know if they go up 1 flight of stairs they will have chest heaviness.
What is Accelerating Angina?
- unstable plaque with intermittent symptoms
- symptoms come and go
What is Acute Coronary Syndrome?
- Non-STEMI
- STEMI(plaque rupture)
What does Acute Coronary Syndrome refer to?
Unstable Angina
STEMI
NSTEMI
What is the focal point in treatment decision strategies for a pt admitted with dx of unstable angina, chest pain or rule-out MI?
12 Lead ECG
-done in the field and transmitted right to the Cath Lab
What is Unstable Angina?
- occurs without cause ex. It wakes you up for sleep
- lasts longer than 15-20 minutes
- responds poorly to nitroglycerin
- may occur along with a drop in blood pressure or significant SOB
What is a NSTEMI?
Non-ST Segment Myocardial Infarction
- ST Segment elevation does NOT occur
- Coronary Artery is only partially blocked
- a smaller portion of cardiac tissue dies since there is not a complete artery blockage- that’s what causes the ST segment depression
- difficult to distinguish form unstable angina without measuring cardiac enzymes
What is a STEMI?
ST Elevation Myocardial Infarction
- ST elevation does occur indicating complete blockage of the coronary artery, occlusive clot
- a larger amount of cardiac tissue dies
- more sever than NSTEMI
- early intervention critical -door to ballon time <60 minutes!
What are the 3 Clues used to Diagnose Chest Pain?
- The first assessment clue is focused around the characteristics of chest discomfort and the physical exam
- The second assessment clue is rapid and accurate interpretation of the 12 lead ECG
- The third assessment clue is the rise and fall of cardiac maker labs
What is the Primary Diagnostic Study that sits at the center of all decision making protocols?
The 12 lead ECG is the primary diagnostic study, although all 3 clues are important.
What is the format of the Printed 12 Lead ECG?
- there are 6 FRONTAL LEADS which are labeled Leads, I, II, III, aVR, aVL, and aVF
- Leads I, II, III represent a picture of the electrical conduction of the heart from view of the limb to the heart
- the sam “a” means AUGMENTED
- the augmented leads show the electrical conduction augmented from the heart to the right arm (aVR) from the heart to the left arm (aVL) and the heart to the right foot (aVF)
- There are 6 PRECORDIAL LEADS/Chest Leads/ V Leads named V1, V2, V3, V4, V5, and V6.** placed at the 4th intercostal space**
I AVR V1 V4
II AVL V2 V5
III AVF V3 V6
What does ST segment inversion/ T wave inversion reflect?
Ischemia
What does ST segment elevation reflect?
-tissues injury
- greater elevation- infarction- tissue death
- development of Q or QS waves
What is the Isoelectric Line?
- electrical activity is resting
- imaginary line on the ECG recording where your PR interval is recorded and where the S segment normally sits
- normal reference point for evaluating ST- T wave abnormalities