Isorhythmic AV dissociation
Results:
Second-Degree AV Block, High-Grade
(Advanced AV Block)
Key Points Definition: A severe form of second-degree AV block—most often Mobitz II—characterized by multiple consecutive non-conducted P waves (e.g., 3:1 or 4:1 conduction). PR Intervals: Constant before conducted beats,…
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…
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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