Table 5Possible diagnoses of tachyarrhythmias based on the electrocardiogram

Shape of complexDiagnosis
Irregular narrow complexAtrial fibrillation
Atrial flutter (sawtooth pattern)
Multifocal atrial tachycardia (distinct P waves, but with different morphologies)
Regular narrow complexSinus tachycardia
Atrial flutter with constant AV block
AVNRT
Accessory pathway re-entrant tachycardia
Irregular broad complexAtrial fibrillation + LBBB/RBBB
Atrial fibrillation + other aberrant conduction
Regular broad complexSinus tachycardia + LBBB/RBBB
Atrial flutter with constant AV block + LBBB/RBBB
Ventricular tachycardia

AV: atrioventricular; AVNRT: atrioventricular nodal re-entrant tachycardia; LBBB: left bundle branch block; RBBB: right bundle branch block.

From: Chapter 8, Arrhythmia

Cover of Cardiology Explained
Cardiology Explained.
Ashley EA, Niebauer J.
London: Remedica; 2004.
Copyright © 2004, Remedica.

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