Also known as sinus dysfunction, sinoatrial node disease, and tachycardia-bradycardia syndrome (a specific variant)
Collection of signs or symptoms that indicate sinus node dysfunction
May present as bradycardia, tachycardia, or alternating bradycardia and tachycardia
50% have alternating bradycardia and tachycardia (i.e. tachycardia-bradycardia syndrome)
50% have alternating bradycardia and tachycardia (i.e. tachycardia-bradycardia syndrome)
Intrinsic:
Degenerative fibrosis
Infiltrative disease process (e.g. amyloidosis)
Ion channel dysfunction
SA node remodeling
Myocardial ischemia
Extrinsic:
Pharmacologic
Metabolic/electrolyte disturbance
Autonomic dysfunction
Obstructive sleep apnea
Degenerative fibrosis
Infiltrative disease process (e.g. amyloidosis)
Ion channel dysfunction
SA node remodeling
Myocardial ischemia
Pharmacologic
Metabolic/electrolyte disturbance
Autonomic dysfunction
Obstructive sleep apnea
Sick sinus syndrome
Regular
Hypertrophic cardiomyopathy
AV Node Independent
Brugada syndrome
Sinus tachycardia
Decompression sickness
Atrial tachycardia 