Ventricular Fibrillation Flashcards
1
Q
What is VF? (2 things)
A
- Life threatening arrhythmia
- Disorganized + High Frequency Ventricular Contractions
2
Q
What does VF result in? (2 things)
A
- Reduced CO
- Haemodynamic collapse
3
Q
How does VF usually start off as?
A
VT w very irreg rhythm
4
Q
What are the causes of VF? (4 things)
A
- Underlying CVS disease (CAD (most common) / MI / myocarditis / cardiomyopathy)
- Congenital heart defects (pulmonary atresia)
- Electrolyte abn (hypokalaemia / hyperkalaemia)
- Electrophysiologic disorders (e.g Wolff-Parkison-White syndrome / Torsade de Pointes)
5
Q
How can VF cause death? (6 steps)
A
- Re-entry of signal
- Chaotic circular excitation of myocardium = VF
- Simultaneous contractions @ multiple foci
- Insufficient CO
- Haemodynamic collapse
- Loss of consciousness / Death
6
Q
How can signal re-entry in VF happen? (2 things)
A
- Changes to conduction pathway (e.g unexcitable scar tissue bc MI)
- Abn excitation pattern (e.g recovery period of myocardial cells longer than AP (long QT syndrome)
7
Q
What are the clinical features of VF? (5 things)
A
- Fatigue / Dizziness
- SOB
- Chest Pain
- Palpitations
- Loss of consciousness / death (ultimately)
8
Q
What are the ECG findings of VF? (5 things)
A
- Commonly preceded by VT
- Arrhythmic, fibrillatory baseline
- Usually 300+ bpm
- Undistinguishable QRS complexes
- No P waves
9
Q
How should underlying conditions of VF be evaluated for? (9 things)
A
- ECG
- Cardiac enzymes
- Electrolytes
- TSH
- Drug levels + toxicology screen
- ABG
- Coronary angiography
- Echo
- Nuclear imaging
10
Q
What are the Resus management options for VF? (2 things)
A
- Defibrillator + Adrenaline
- If fails –> amiodarone / lidocaine
11
Q
What are the Post-resus management options for VF? (4 things)
A
- Continue Resus antiarrythmatics (amiodarone / lidocaine)
- Beta blockers
- Treat underlying causes
- Implantable Cardioverter Defibrillator (ICD) (if NO reversible cause / haemodynamically significant VF)
