🩻ECG Flashcards
(29 cards)
Automaticity
ability of heart cells to generate action potential
Conductivity
ability for cardiac cells to transmit action potential
Rhythmicity
cardiac cells to generate an action potential in a regular rate
SA node rate
60-100 beats/min
AV node rate
40-60 beat/min
Purkinje fibers
15-40 beat/min
P wave
artial depolarization/contraction
SA firing
PR interval
time from onset art depo to vent depo
QRS interval
Art repo/vent depo
Impulse through bundle branches down purkinje
J point
point after QRS when returns to isoelectric line
ST segment
end of QRS to beginning of T wave
Elevated ST
STEMI
ST depression
NSTEMI
T wave
vent repo
influenced potassium
QT interval
time from vent depo to vent repol
Q to end of T (at isometric line) ~ 40 seconds
Systematic Approach
calculate rate, regularity, rhythm
Regularity
R to R, P to P
PR interval
0.12 - 0.2 sec 3-5 little boxes
QRS interval
<0.12 less than 3 boxes
What can prolong QT interval
amiodirone
First degree AV block
P interval longer than >0.20
Bundle Branch Black BBB)
> 0.12 prolonged QRS interval
could indicate previous MI
Artifact
different strip, reposition, pulm treatment
Normal Sinus Rhythm
Impulse 60-100
P wave present
PR interval within .12-.20
QRS is narrow <0.12s seconds
