Arrhythmias Flashcards
(20 cards)
4 types of arrhythmia?
- Ventricular fibrillation
- Ventricular tachycardia
- Pulseless electrical activity
- Asystole
Differential for a narrow QRS?
- Atrial fib
- Atrial flutter
- Supraventricular tachy
Broad QRS complex?
- Ventricular tachy
- SVT with BBB
What is atrial flutter?
Re-entrant contraction into either Atria due to an extra loop in the heart .
Atrial contraction- 300bpm
Ventricular contraction every second loop- Ventricular rate of 150bpm
ECG in atrial flutter
- Sawtooth appearance
- Abnormal P waves
- Rate of flutter P waves to QRS complexes is 2:1
- HR of 150bpm
Treatment of atrial flutter
- Rate/ rhythm control
- Radiofrequency ablation
- Anticoagulation based on CHA2DS2VASC score
SVT
Due to re-entrance of signal from the ventricles to the atria.
Once back in the atria, the signal passes back through the AV node to the ventricles where it causes them to contract again.
Leads to a self-perpetuating loop
3 main types of SVT
- Atrio-ventricular nodal re-entrant tachycardia - re-entry via AV node
- Atrioventricular re-entrant tachycardia - re- entry via accessory pathway
- Atrial tachycardia- electrical activity generates outside of SAN
Management of SVT
Acute management of a
- valsalva manœuvre
- Carotid sinus massage
- Adenosine/ Verapamil - interrupts the AV node/ accessory pathway and it slows down conduction through the AV node
- Direct Current cardioversion
Long term
- CCB, BB, Amiodarone
- Warfarin
- Radiofrequency ablation
Wolf- Parkinson white syndrome
Presence of an extra pathway which connect the atria to the ventricles.
Known as the WPW pathway or the Bundle of Kent
Presentation of WPW on ECG?
Delta wave
Wide QRS
Narrow PR
Ventricular tachycardia
- Premature ventricular contractions which lead to tablespoons of blood being pumped out
Investigations of VT
ECG
- no P waves
- Wide QRS
Bloods: troponin- may be indicative of ischaemia
Common VT?
Torsades de points VT
Due to afterdepolarisations: further depolarisation to the ventricles before they have been re-polarised
Management of VT
- Cardioversion
- Radio-frequency ablation
- Insertion of ICD: implantable cardioverter defibrillator
Presentation of VT
- Dizziness
- Fatigue
- SOB
- Palpitations
Aetiology of VT
May be associated with Ischaemia/ MI
Drug use
What is ventricular fibrillation
Ventricles not contracting at the same time
Muscles move around like a bag of worms
Not enough power to push out blood
Investigation
- No QRS
- No P waves
- Unmeasurable QRS
Classification of VT
Sustained
- HR of 100bpm
- Lasting 30 seconds
Unsustained
- HR of 100bpm
- Lasting for at least 3 consecutive beats
- Lasting less than 30 seconds
