Dysrhythmias Below The AV Node Flashcards
Ectopic focus from ventricle (cell decides to contract early/out of order)
Ventricular depolarization occurs BEFORE SA node fires
WIDE QRS bc stimulation occurs BELOW AV node
NO P wave
COMPENSATORY PAUSE to reorganize SA and AV nodes for impulse conduction
PVC
PVC
Ectopic focus from a ventricle (cell decides to contract early/out of order)
Ventricular depolarization occurs BEFORE SA node fires
WIDE QRS bc stimulation occurs BELOW AV node
NO P wave
COMPENSATORY PAUSE after the PVC to reorganize SA and AV for impulse conduction
Are PVCs abnormal?
No
PVC telemetry characteristics…
Compensatory pause ==> beat after PVC feels like a "thump in the chest" bc the ventricles have a lot of time to fill c blood bc of the compensatory pause Bigeminy Trigeminy Couplet Unifocal Multifocal
Bigeminy
Every OTHER beat is PVC
Trigeminy
Every THIRD beat PVC
Couplet
TWO PVCs paired together
Unifocal
PVCs all the same –> same irritated area in Vs causing the early contraction
Multifocal
PVCs appear different –> more than one area irritated and they all contribute to early contraction
PVC potential causes…
Caffeine/energy drinks Nicotine Stress Overexertion Hypo- or hyperkalemia Ischemia Cardiomyopathy Cardiac irritation
PVC characteristics
Increased frequency ==> decreased filling time ==> DECREASED PRELOAD ==> decreased SV ==> decreased CO
Decreased CO is dangerous c PVCs when…
Couplet Multifocal > 6/min. Triplets *termination points for activity ==> can degrade to life-threatening rhythm*
May progress to V-tach or V-fib
Anti-arrhythmia
It is important to note if PVCs…
Increase c exercise
Decrease c exercise
Stay the same c exercise
monitor BP and sx for termination points
Should premature beats be taken into consideration when calculating HR?
No - HR should be calculated on a part of the strip that does not contain the PVCs
3 or more consecutive PVCs
NO P wave
WIDE QRS (bc impulse BELOW AV node)
V rate 100-250bpm
V-tach
When is the QRS wide?
When the impulse comes from BELOW the AV node
V-tach
3 or more consecutive PVCs
NO P wave
WIDE QRS (bc impulse comes from BELOW AV node)
V rate 100-250bpm
V-tach V rate…
100-250bpm
V-TACH =
EMERGENCY
V-tach possible causes…
Ischemia/infarction CAD HTN Digoxin Electrolyte imbalance
V-tach management
Cardioversion (time c QRS)
Defibrillation (increased Joules of energy to reset the rhythm)
V-tach characteristics
CO greatly affected ==> decreased HR, decreased filling time, NO atrial contraction Lightheadedness Syncope Angina Weak, thready pulse Disorientation
V-tach telemetry characteristics…
NO P wave
WIDE QRS
“Twisting of the points”
Torsades de Pointes
Torsades is a characteristic of…
V-tach
Torsades occurs when…
V-tach changes axis ==> bad prognostic factor that makes the V-tach harder to defibrillate
Characteristics of torsades
Twisting around the isoelectric line
Occurs during V-tach
Significant drop in CO
Cardioversion
Quivering of ventricles, so no real contraction, and the atria do not really contract much
NO CO
Multiple ectopic foci –> contractions not synchronous
Zig-zag pattern
Progression of V-tach
V-fib
V-fib
Quivering of ventricles, so no real contraction, and the atria don’t really contract much
NO CO
Multiple ectopic foci c no synchronous contraction
Zig-zag pattern
Progression of V-tach
V-FIB =
EMERGENCY
V-fib possible causes…
Progression of V-tach
Infarction/ischemia
HTN
Digoxin toxicity
V-fib management
Defibrillation
CPR
O2
Meds
Altered electrical conduction during angina
T wave inversion
T wave flattened or peaked
Changes in ST segment at least 1mm (elevation is STEMI; depression if NSTEMI)
MI
The zone of ischemia in an MI looks like what on a telemetry strip?
T wave inversion or flattening
The zone of infarction in an MI looks like what on a telemetry strip?
Q wave/STEMI (elevated) (transmural MI) –> > 0.04 sec; at least 1/4 the heigh of R wave in same QRS
Non Q-wave/NSTEMI (depressed) (sub-endocardial MI) –> area of myocardium can re-infarct if not managed
Bundle branch blocks
