Arrhythmias Flashcards
what defines an arrythmia (2)
- too fast or slow 60-100
2. or irregularity
what are 3 ways sinus rhythm can be off
- sinus arrhythmia
- sinus bradycardia
- sinus tachycardia
2 main mechanisms of brady
- anatomic/structural
2. physiological - ion channel
2 causes of anatomic brady
- surgery
2. fibrosis - both affecting SA node
3 ways of ion brady
- autonomic tone
- genetic
- drugs
2 points bradycardia can occur
- sinus arrest (SA)
2. heart block (AV node)
2 ECG signs of sinus bradycardia
- 3sec
3 degrees of heart block and definition
- long PR interval
- intermittent conduction - AV wenkebach
- complete AV block - SA goes, but doesn’t hit vent.
what happens in 2 types of second degree AV block
- PR interval gets longer until skip a beat and resets
2. no variation in PR before block - miss every second beat
what are likely causes of types 2
distal conduction diseases
what happens on ECG in 3rd degree
P wave going normally, QRS goes at its own slower pace - requires pacer
where can tachy arise
both conduction system and myocardium
2 major mechs. of tachy
- automaticity
2. reentry
what is automaticity
restarting an action potential - normal in conduction system, not normal in myocardium
what are 2 types of abnormal automaticity
- early afterdepolarization
2. delayed afterdepolarization
what are extrasytoles
abnormal early beats that originate in either chamber
what is re-entry
beat coming back around and starting a new one
4 conditions for re-entry
- unidirectional block
- slowed conduction
- fixed anatomic block
- functional arc of block
3 types of atrial myocardium tachyarrythmias
- atrial flutter
- atrial fibrillation
- ectopic atrial tachcardia
2 types of ventricular tachyarrythimas
- vent. tachycardia - onset in bottom
2. vent. fibrillation
ECG sign of vent. tachycardia (2)
- wide ventricular beat (QRS>140)
2. AV dissociation
diff between vent. tachycardia vs. fibrillation
fibrillation if much more chaotic
consequences of Vent tachycardia
- hemodynamic compromise
- life threatentnig
consequences of fibrillation
- disrodered activity without effective contraction
- not compatible with life
- most out of hospital cardiac arrests
