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Sick sinus syndrome differential diagnosis

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Sahar Memar Montazerin, M.D.[2]

Overview

Sick Sinus Syndrome Differential Diagnosis

Sick sinus syndrome must be differentiated from other cause of syncope, lightheadedness, dizziness, and tachycardia-bradycardia syndrome. This algotithm shows different types of bradycardia:

 
 
 
 
 
 
 
 
 
Bradycardia Differential Diagnosis
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Bradycardia
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Narrow complex
 
 
 
 
 
 
 
 
 
 
 
 
Wide complex
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Regular
 
Irregular
 
 
 
 
 
 
 
 
Regular
 
Irregular
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Sinus bradycardia
Junctional bradycardia
Complete AV block (junctional escape)
Atrial flutter with high degree block
 
• Sinus arrhythmia, pause or arrest
• Sinoatrial exit block (second degree)
• AF with slow ventricular response
Atrial flutter with variable block
Second degree AV block, type I
Second degree AV block, type II
 
 
 
 
 
 
 
 
• Idioventricular rhythm
Complete AV block (ventricular escape)
• Sinoventricular rhythm
• Regular bradycardias with aberrancy or bundle branch block
 
Second degree AV block, type I
Second degree AV block, type II
• Sinoatrial exit block (second degree) with bundle branch block
• Irregular bradycardias with bundle branch block

References

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