Junctional, Ventricular Dysrhythmia & AV Blocks Flashcards
If P waves can be seen in a junctional rhythm, they would appear inverted in which leads?
II, III, aVF (inferior leads)
Inverted P waves with a short or absent PR interval is indicative of…
junctional dysrhythmia
a single early impulse arriving from the AV junction…
premature junctional contraction
Rhythm: Irregular, one premature beat
P Wave: inverted, may be after or in the QRS
P-R Interval: short ( < 0.12s)
premature junctional contraction
If you can’t decide whether a rhythm is atrial or junctional arrhythmia, what can determine it as junctional?
shortened PR (impulse was generated lower down, so therefore shorter duration)
Rate: 40 - 60 bpm
P waves: inverted in leads II, III, aVF
PR Interval: short (< 0.12s)
Junctional Escape Rhythm
Rate: 60 - 100 bpm
P waves: inverted or absent in leads II, III, aVF
PR Interval: short (< 0.12s)
Accelerated junctional rhythm
Rate: 100 - 180
P waves: inverted, may be hidden in or occur after QRS
PR: shortened
Junctional Tachycardia
What class of dysrhythmias?
Wide, bizarre QRS complexes > 0.12s
T waves in opposite direction of R wave
No P waves
ventricular dysrhythmias
Rhythm: Irregular due to one premature beat
P waves: not visible
QRS: wide, bizarre ( > 0.12s)
T waves: opposite direction of R wave
Premature Ventricular Complex
Is there a full compensatory pause after a PVC?
yes
PVCs that look the same are called ______ and are (more/less) dangerous
unifocal, more dangerous
PVCs that look different from one another are called…
multifocal
What is it called when 2 PVCs occur in a row, what does this signify?
couplet, extremely irritable ventricles
a couplet of PVCs can cause…
lethal arrhythmia
PVCs that fall between two regular complexes and don’t disrupt the normal cycle are called…
interpolated PVCs
PVCs occurring on or near the previous T wave are called _______. they may precipitate (2)
R-on-T PVCs
precipitate V tach or V fib
Rate: 20 - 40 bpm
Rhythm: Regular
P waves: not visible
QRS: wide, bizarre, ( > 0.12s)
T waves: opposite direction of R wave
idioventricular rhythm
What is the rhythm of last resort?
idioventricular rhythm
if there is one idioventricular beat, what is it called?
ventricular escape beat
Rate: 40 - 100 bpm
Rhythm: regular
P waves: absent
QRS: wide, bizarre, ( > 0.12s)
T waves: opposite direction of R wave
accelerated idioventricular rhythm
Rate: 100 - 250
P waves: absent
QRS: wide, bizarre, ( > 0.12s)
T waves: opposite direction of R wave
Ventricular tachycardia
3 or more PVCs in a row indicates…
ventricular tachycardia
VT may come in a burst of 6 to 10, or may persist. Persistant VT is called
sustained VT
if the appearance of each QRS complex in VT are similar, it is called…
monomorphic
If the QRS appearance varies considerably among complexes in VT, it is called
polymorphic
This is a unique polymorphic VT associated with prolonged QT from dugs or lyte imbalances
Torsades de Pointes
torsades (TdP) is managed via ______ if cardiac arrest, or ______ if not in cardiac arrest.
cardiac arrest = defibrilation
non-cardiac arrest = magnesium sulfate
Ventricular fibrillation has what physical three characteristics
cardiac arrest
unresponsive
pulseless
Rate: 300 - 500
Rhythm: totally chaotic
QRS: illogical wavy, chaotic
ventricular fibrillation
complete cessation of cardiac output represented by a flat line
asystole
organized electrical rhythm on ECG, but pulseless, apneic patient
PEA
The below are reversible causes of…
hypovolemia,
pericardial tamponade, tension pneumothorax,
massive acute MI, drug overdose,
PEA
What type of AV block?
consistent delay in AV node conduction
1st degree
What type of AV block?
intermittent block at AV node, progressive P-R interval lengthening
2nd degree Type I
What type of AV block?
intermittent block at the bundle of his or bundle branches
some atrial impulses don’t get conducted to ventricles
2nd degree Type II
What type of AV block?
complete block of conduction at or below the AV node. Atrial impulses never reach the ventricles
3rd degree AV block
Regular rhythm
P Waves: normal
QRS: normal
P-R interval: prolonged ( > 0.20s)
1st degree AV block
Rate: normal (atria)
Rhythm: patterned irregularity
P waves: present normal looking. Not all followed by QRS
PR Interval: Progressive lengthening until a complex is dropped
2nd Degree AV Block Type I
“Wenckebach” or “Mobitz I”
PR interval prolonged, but the duration of PR interval remains constant
More P waves than QRS complexes
2nd degree AV Type II
PR interval is prolonged
every other p wave is conducted
2:1 AV block
Is type 1 or type 2 AV block more serious?
Type II
3rd degree AV block is also called…
complete heart block
QRS complexes in 3rd degree AV block would appear wide under what condition?
escape focus is ventricular
Rate: normal (atria)
rhythm: normal in atria and ventricles, but not related
P waves: normal, but not related to QRS
March thru QRS complexes
3rd degree AV block
If ventricular rhythm in a 3rd degree AV block is between 40-60, where is the focus/
Junction
If ventricular rhythm in 3rd degree AV block is 20-40, where is the focus?
ventricles
