Clinical Notes : Cardiology
175. ECG - Atrial Fibrillation
Irregularly irregular rhythm.
No P waves.
Absence of an isoelectric baseline.
Variable ventricular rate.
QRS complexes usually < 120 ms unless pre-existing bundle branch block, accessory pathway, or rate related aberrant conduction.
Fibrillatory waves may be present and can be either fine (amplitude < 0.5mm) or coarse (amplitude >0.5mm).
Fibrillatory waves may mimic P waves leading to misdiagnosis.
Commonly AF is associated with a ventricular rate ~ 110 – 160.
AF is often described as having ‘rapid ventricular response’ once the ventricular rate is > 100 bpm.
‘Slow’ AF is a term often used to describe AF with a ventricular rate < 60 bpm.
Dr Ed Burns,
Life in the Fast Lane
last update March 16, 2019