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Sinus Arrhythmia



  • Sinus arrhythmia occurs physiologically due to changes in intrathoracic pressure and resultant variation in vagal tone through the respiratory cycle.
    • Look For

    • Irregular RR interval
    • Normal PR interval with P waves preceding each QRS complex
    • Normal axis - positive P waves in leads I and II
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Adan V, Crown LA. Diagnosis and treatment of sick sinus syndrome. American family physician. 2003 Apr;67(8):1725-32.
 Mangrum JM, DiMarco JP. The evaluation and management of bradycardia. New England Journal of Medicine. 2000 Mar 9;342(10):703-9.