EKG Interpretation Flashcards
7 conduction points in the electrical conduction of the heart
SA node/Internodal and Intraatrial pathways/AV node/ Bundle of His / L and R Bundle Branches / Purkinje fibers
Electrical flow that shows a positive deflection
Electrical flow that shows a negative deflection
- to +
+ to -
PRI should be how long
QRS should be how long
For a rhythm to be regular, the _____ has the same interval
.12-.20 seconds
less than .12 seconds
R-R interval
4 types of arrythmias that are categorized by their pacemaker impulse
sinus, atrial, junctional, ventricular
wandering pacemaker is caused when:
the pacemaker roles switch from beat to beat from the SA node to the atria and back again
Atrial tachycardia
caused by a signal focus in the atria that fires rapidly to override the SA node and thus assumes pacemaking responsibility for the entire rhythm
atrial flutter
an atrial arrhythmia that occurs when ectopic foci in the atria exceed a rate of 250-350 bpm
atrial fibrillation
atria become irritable and are no longer beating, but quivering from multiple pacemaker sites
junctional arrhythmia biggest clue
inverted P-wave or absent P-wave
PJC
single ectopic beat that comes from the AV junction
1st degree heart block
least serious of all heart blocks because it only delays conduction and allows all impulses through to the ventricles
PRI is >.20 and constant
2nd degree heart block
heart block that block some conduction but not all. not every P wave is followed by a QRS (type I and II)
2nd degree type I rules
Irregular
slightly lower rate
uniform upright P, some not followed by QRS
PRI progressively lengthens until one P wave is blocked
2nd degree type II rules
P-P regular / R-R regular or irregular
usually bradycardia
uniform upright P’s, more than 1 P for every QRS
PRI is constant can be >.20
3rd degree heart block rules
regular AR 60-100bpm VR 40-60 Junc 20-40 bpm uniform upright P's, more P's than QRS no relationship with PRI QRS: .12 ventricular
What are the requirements for formation of reentrant focus?
2 pathways of conduction (slow and fast) and an area of unidirectional block secondary to prolonged reformatories in one of the pathways
This is the time from atrial depolarization to ventricular depolarization
P:QRS ratio
This is the interval we measure for heart rate
R-R interval
This is the duration of the atrial cycle
P-P interval
This is the time from the onset of atrial depolarization to onset of ventricular depolarization
P-R interval
This is the time from depolarization to depolarization of the ventricles
QT interval
This wave correlates to ventricular repolarization
T wave
This correlates to ventricular depolarization
QRS
This wave correlates to atrial depolarization
P wave
