Rapid EKG II Flashcards
sinus rhythm
created at SA node
-60-100 bpm
bradycardia
<60
tachycardia
> 100
ectopic foci
auto foci other than SA node
atrial foci rate
60-80
junctional foci rate
40-60
vetnricular foci rate
20-40
overdrive suppression
fastest foci is in control
AV junction foci
proximal end - no foci
-rate 40-60
can cause idiojunctional rhythm
rate numbers to know
300-150-100-75-60-50
6 second strip
with two three second intervals
sinus arrhythmia
normal physio mechanism
- slight increase with inspiration
- sympathetic
- slight decrease with expiration
- parasympathetic
bachmanns bundle
SA node to left trium
atrial conduction system
middle, posterior, and anterior internodal tracts
also - bachmanns bundle
AV node near coronary sinus
likely spot of automaticity - bc convergence of several conduction pathways
septum depolarization
left bundle branch has terminal filaments
right bundle branch - no terminal filaments in septum
U wave
final phase of purkinje repolarization
beyond end of T wave
irregular rhythm
inconstant duration between paced cycles
parasystolic**
if foci has entrance block
- cannot be overdrive suppressed
- can become pacing foci
wandering pacemaker
P wave shape varies
atrial rate <100
irregular QRS complexes - still narrow
P wave shape varied
atrial rate <100
irregularly space narrow QRS
wandering pacemaker
multifocal atrial tachycardia
P wave shape varies
atrial rate >100
irregular narrow QRS
**often with COPD
P waves varied
atrial rate >100
irregularly spaced narrow QRS
multifocal atrial tachycardia
atrial fibrillation
no discernable P waves
- chaotic atrial spikes
- random narrow QRS complexes
**random depolariations reach the AV node
**important to determine rate average - per six second strip
chaotic atrial spikes - no P waves
-random narrow QRS complexes
atrial fibrillation
escape rhythm
auto foci escapes overdrive to pace at its inherent rate
-atrial, junctional, and ventricular
escape beat
auto foci escapes overdrive to emit one beat
-atrial, junctional, ventricular
sinus arrest
SA node ceases pacemaking completely
-backup auto foci take over
atrial escape rhythm
sinus arrest - followed by atrial foci that takes over
- rate 60-80
- new P’ waves
junctional escape rhythm
sinus arrest leads to auto foci in junction to take over
- rate 40-60
- P’ inverted with upright QRS
- retrograde atrial depolarization
P’ inverted with upright QRS
seen with junctional escape rhythm
-due to retrograde atrial depolarization
may be before, during, or after QRS
ventricular escape rhythm
ventircular auto foci takes over
- rate 20-40
- widened QRS complexes
- no P waves
stokes adams syndrome
ventricular pacing - very slow
- reduced blood to brain
- patient unconscious
downward displacement of the pacemaker
total failure of SA node and all foci above ventricles
- rare
- ventricular foci takes over
atrial escape beat
sinus block results in pause allowing atrial foci to take over for one beat
-see a different P’
junctional escape beat
sinus block results in pause allowing junctional foci to take over
-inverted P’ or no P’
ventricular escape beat
sinus block results in pause allowing ventricular foci to take over
- no P wave
- widened QRS complex
cardia parasympathetics
inhibit SA node and atrial/junctional nodes
-therefore, burst of PS leaves ventricular foci to respond to pause
premature beat
irritable focus spontaneously fires single stimulus
-atrial, junctional, or ventricular
-appears earlier than expected
ventricular foci
O2 sensitive
-low O2 - irritable - react
irritation of atrial and junctional foci
epi, sympathetics, caffeine, stimulants of beta1, hyperthyroid, stretch
-can fire impulse
