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Sick sinus syndrome

Last updated: March 20, 2020

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Sick sinus syndrome (SSS) refers to the dysfunction of the sinoatrial node and is responsible for several types of arrhythmia. It comprises bradyarrhythmias (e.g., sinus bradycardia, sinoatrial pauses, blocks, and arrest), and may alternate with supraventricular tachyarrhythmias, in which case it is referred to as tachycardia-bradycardia syndrome. The most common SSS arrhythmias are sinus bradycardia and non-respiratory sinus arrhythmia. SSS typically occurs in the elderly. Depending on the extent of bradycardia or tachycardia, the condition may be asymptomatic or present with symptoms such as palpitations or dyspnea. More serious manifestations, such as lightheadedness and syncope, are indications for pacemaker placement.

References:[1]

Symptoms vary or may be entirely absent depending on the extent of bradycardia or tachycardia.

References:[1][2][3][4]

Symptoms or ECG findings may be inconclusive if considered on their own. Therefore, it is very important to establish a correlation between the underlying rhythm and symptom manifestation.

References:[1][2][3]

Management depends on the symptoms of each patient, most notably on the length of sinus pauses.

References:[3]

  1. Homoud MK. Sick sinus syndrome: Epidemiology, etiology, and natural history. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/sick-sinus-syndrome-epidemiology-etiology-and-natural-history?source=search_result&search=sick%20sinus%20syndrome&selectedTitle=3~150#H6105633.Last updated: May 4, 2016. Accessed: December 15, 2016.
  2. Yang Y. Sinus Node Dysfunction. In: Rottman JN, Sinus Node Dysfunction. New York, NY: WebMD. http://emedicine.medscape.com/article/158064-overview. Updated: December 31, 2015. Accessed: December 15, 2016.
  3. Homoud MK. Sick sinus syndrome: Clinical manifestations, diagnosis, and evaluation. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/sick-sinus-syndrome-clinical-manifestations-diagnosis-and-evaluation?source=search_result&search=sick%20sinus%20syndrome&selectedTitle=1~150.Last updated: May 4, 2016. Accessed: December 15, 2016.
  4. Homoud MK. Sick sinus syndrome: Treatment. In: Post TW, ed. UpToDate. Waltham, MA: UpToDate. https://www.uptodate.com/contents/sick-sinus-syndrome-treatment.Last updated: May 4, 2016. Accessed: December 15, 2016.
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  7. Brubaker PH, Kitzman DW. Chronotropic Incompetence: Causes, Consequences, and Management. Circulation. 2011; 123 (9): p.1010-1020. doi: 10.1161/circulationaha.110.940577 . | Open in Read by QxMD
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  10. 2018 Guidelines Made Simple: Bradycardia and Cardiac Conduction Dela. https://www.acc.org/guidelines/hubs/bradycardia-and-cardiac-conduction-delay. . Accessed: January 14, 2020.
  11. Issa ZF, Miller JM, Zipes DP. Clinical Arrhythmology and Electrophysiology. Elsevier Health Sciences ; 2012
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