Sick sinus syndrome

Background

  • Collection of bradyarrhythmias with or without tachycardia[1]
  • 50% have alternating bradycardia and tachycardia

Causes

  • Intrinsic:
    • degenerative fibrosis
    • infiltrative disease process
    • ion channel dysfunction
    • SA node remodeling
  • Extrinsic:
    • pharmacologic
    • metabolic/electrolyte disturbance
    • autonomic, OSA

Clinical Features

  • Clinical manifestations related to end-organ hypoperfusion
    • Syncope/pre-syncope (50%)

Differential Diagnosis

Symptomatic bradycardia

Evaluation

  • ECG identification, inpatient telemetry, outpatient Holter monitoring, event monitoring, loop monitoring
    • ECG frequently negative for findings early in disease course

Management

  • remove extrinsic factors and/or pacemakers
    • Pacemakers do not reduce mortality, only decrease symptoms

Disposition

  • Admit

Complications

  • (50%) Tachy-brady syndrome with atrial fibrillation or atrial flutter
  • (50%) AV block

See Also

External Links

References

  1. Semelka, M et Al. Sick Sinus Syndrome: A Review. Am Fam Physician. 2013 May 15;87(10):691-696. http://www.aafp.org/afp/2013/0515/p691.html