Summary ECG Tachyarrhythmias

ECG Tachyarrhythmias
Definition Tachycardia: Heart rates >100bpm
ECG characteristics
 QRS
o Wide vs Narrow complex
 Regular vs Irregular
 P waves


Narrow complex tachycardias Wide complex tachycardias
 Action potential starts in the atria  Action potential starts in the
ventricle
Atrial fibrilation Ventricular tachycardias
 Irregular
Atrial flutter Supraventricular tachycardia with aberrancy
Sinus tachycardia Supraventricular tachycardia with pre-
AV-Nodal Re-entry Tachycardia (AVNRT) excitation
AV Re-entry Tachycardia (AVRT)  e.g. Wolf-Parkinson-White


Identify the origin of the beat (Chapter conduction diseases)
 Sinus beat
 Atrial beat
 Junctional (AV nodal) beats
 Ventricular beats

, Atrial Fibrillation  Disorganised activation of the atria
 No P waves
 Irregular ventricular rate
 Most common sustained arrhythmia
Atrial Fibrilation on ECG
 Irregularly irregular rhythm  First differential must be atrial fibrilation
 No P waves
 Unstable baseline (fine and coarse fibrilation waves)
 Narrow QRS
o Unless other conduction pathology present