Sick sinus syndrome

Background

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

Clinical Features

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

Differential Diagnosis

Causes

1. Intrinsic:
   1. degenerative fibrosis
   2. infiltrative disease process
   3. ion channel dysfunction
   4. SA node remodeling
2. Extrinsic:
   1. pharmacologic
   2. metabolic/electrolyte disturbance
   3. autonomic, OSA

Workup

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

Management

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

Disposition

Admit

Complications

1. (50%) Tachy-brady syndrome with atrial fibrillation or atrial flutter
2. (50%) AV block

See Also

• Symptomatic Bradycardia