Flashcards in Arrhythmias (Sandilands flow chart) Deck (11)
What ECG morphologies are used to categories tachycardias?
- Narrow vs Broad complex QRS
- Regular vs irregular R-R intervals
- Presence of P waves
Name 4 regular arrhythmias associated with P waves and narrow QRS complexes
- Sinus tachycardia
- Atrial flutter
- SVT (AVRT)
- Ectopic atrial tachycardia
Name the regular narrow QRS complex arrhythmia without P waves
AVN re-entrant tachycardia
Describe atrioventricular re-enterant tachycardia
Formation of an accessory pathway between the atria and ventricles enable conduction to spread up from the ventricles into the atria.
The atria contract earlier than the SAN ➔ tachycardia unto 200-300bpm
Define Wolff-Parkinson-White Syndrome
Episodes of tachycardia, with the presence of a congenital accessory pathways (Bundle of Kent).
Asymptomatic referred to as having WPW pattern on ECG.
Delta waves are characteristic of WPW.
Describe AVN re-entrant tachycardia
Premature atrial beat travels down (anterograde) the slow alpha pathway and up (retrograde) the fast beta pathway whilst it is still in its long refractory period.
This creates a slow-fast (typical AVNRT) re-entry loop that continuously depolarises the bundle of His ➔ tachycardia.
Outline the presentation of AVRT and AVNRT
Short-duration symptoms of palpitations, SoB, dizziness, syncope (rare). Rarely life-threatening.
Commonly terminated by Valsalva manoeuvres.
Outline management of AVRT and AVNRT
- Valsalva manoeuvre or carotid sinus massage
- IV adenosine: highly effective for AVRT and AVNRT
NB. Adenosine contraindicated in asthmatics
- Rate control (Beta-blockers, CCBs, digoxin)
- DC cardioversion
- Accessory pathway ablation: definitive Tx
Differentiate Atrial Fibrillation and Atrial Flutter
Atrial fibrillation is an irregular-irregular tachycardia without P waves. Wavy baseline is typical. Disorganised contraction of atria.
Atrial flutter is a regular tachycardia with P waves. Sawtoothing is typical. Generally faster rate than AF. Organised contraction of atria ➔ more impulses pass the AVN
Outline the types of ventricular arrhythmia
-Life-threatening ventricular tachyarrhythmias
-Normal heart ventricular tachycardia
-Non-sustained ventricular tachycardia