Medical Archive

Introducion

60? ?? (??? 50?), Hypoxemia? ?? ?? ??
Stable ?? observe
Unstable?? ?? ?? (?? or ??)

Structure and physiology of the SA node

Etiology of SA nodal disease

Clinical features of SA node disease

Sick sinus syndrome

• Pathophysiology
  • In elderly patients.
  • Age-related degeneration of the cardiac conduction system with fibrosis of the sinus node – m/c
  • Ischemia and infiltrative cardiac disease – other potential causes
• Bradycardia
  • Fatigue, dyspnea, dizziness, syncope
• Bradycardia-tachycardia syndrome
  • Atrial arrhythmias (eg, atrial fibrillation), palpitations
• Chronotropic incompetence
  • Inadequate heart rate response to exercise

ECG of SA node disease

Bradycardia with sinus pauses(delayed P), sinus arrest(dropped P), junctional escape rhythm

Sick sinus syndrome

Sinus bradycardia
Sinus pauses (delayed P waves)
Sinoatrial nodal exit block (dropped P waves)
Tachy-brady syndrome

Diagnostic testing

Treatment

• Medication
  • Atropine (2? II, 3?? X) > dopamine, epinephrine
  • Once a pacemaker is placed, Rate-control with BB
• Transcutaneous pacing
• Pacemaker
• ?? ?? ??? ??? ?? ?? ??? ?? SaO2? ?? ???? ?? ??? ??

• Sinus pause (sinus arrest)
  • ?? (-): ??
  • ?? (+): permanent pacemaker
• Sinoatrial (exit) block
  • ?? ????? ??? ??? ?? ?? ??
• Sinus bradycardia
  • ?? (-): ??
  • ?? (+): atropine, isoproterenol
  • ?? (+) & ?????? ????? ?? ?: pacemaker
  • ?? (+) & SA nodal artery ischemia? ?? ??: ?? ?? or atropine
• Sinus arrhythmia
  • ?? ????? ?? ?? ??
• Sick sinus syndrome
  • Permanent pacemaker (DDD)
  • Chronotropic incompetencer? ??? DDDR.