Isorhythmic AV dissociation
Results:
Third-Degree AV Block (Complete Heart Block)
Key Points Definition: Third-degree AV block is complete failure of conduction from atria to ventricles, resulting in independent atrial and ventricular activity—known as AV dissociation. Hallmark Feature: No P waves…
High-Grade (Advanced) AV Block
Key Points Definition: A severe form of second-degree AV block with two or more consecutive non‑conducted P waves (for example 3:1, 4:1). Do not force a Mobitz label when multiple…
Distinction Between AV Dissociation and Complete Heart Block
A 54-year-old man presents to the emergency department with chest pain. The following ECG is obtained:
STAT ECG Diagnoses: Isorhythmic AV Dissociation and Complete Heart Block
A 43-year-old man with a history of demand pacemaker placement gets the following routine ECG during outpatient follow up with his primary care provider:
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