Sick sinus syndrome

Also known as: Sinus node dysfunction; tachycardia–bradycardia syndrome

Impaired sinus node impulse formation or exit, causing bradycardia, pauses or alternating tachycardia and bradycardia.

Medical specialty: Cardiology
Subspecialty: Cardiology / Cardiac electrophysiology
Sex & age distribution: Male: affected; Female: affected equally to slightly higher; Children: yes, in congenital or post-surgical cases; mostly elderly
Gene(s) involved: ANK2, CACNA1D, GNB2, HCN4, KCNJ3, MYH6, SCN5A

Etiology & mechanism

Age-related fibrosis, ischemia, drugs or inherited ion channel defects reduce pacemaker function.

Gene(s) involved (7)

ANK2CACNA1DGNB2HCN4KCNJ3MYH6SCN5A

Symptoms & signs (8)

atrial fibrillationbradycardiadizzinessexercise intolerancefatiguepalpitationssinus pausessyncope

SyndromeScope — educational reference. Content is model-generated and not clinically verified; always confirm against OMIM, Orphanet and GeneReviews before clinical use.