ECG Tutorial Flashcards
(23 cards)
How do you calculate the regular heart rate?
300
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R-R Interval
What is the P-R interval?
AV node delay
Why is there a delay in the AV node?
To allow full emptying of the atrium
How do you calculate the irregular heart rate?
Number of R waves in 6sec x10
How long should the P-R interval be?
0.12-0.2s
What is indicative of prolonged P-R interval?
AV Block
How long should the QT interval be?
Less than 0.44s
How long should the QRS complex be?
0.06-0.12s
Which leads are normally inverted?
aVR
V1
V2
aVL
what do the augmented leads measure?
The average electrical energy between two limb leads
Which lead gives a view of the heart from the left?
Limb lead 1
What lead gives an inferior right view of the heart?
Limb lead 3
What lead gives inferior left view of the heart?
Limb lead 2
Where does limb lead 1 span from?
Right to left arm
Where does limb lead 2 span from?
R arm to L leg
Where does limb lead 3 span from?
L arm to L leg
What is the cardiac axis?
IS the net flow of electrical activity in the heart
What view does the aVR lead give?
Upper right
What view does the aVL lead give?
Upper left
What view does the aVF lead give?
Inferior wall
What lead is usually flat and why?
aVL as it runs perpendicular to the flow of electricity
Why are some leads inverted?
Run in different direction to electrical flow
When is there a risen ST segment?
Acute myocardial infarction
