SCN5A Gene Cellosaurus Disease Terminology MYH6 Gene CTCAE Adverse Events Version 4.0 Terminology HCN4 Gene Syndrome Non-Neoplastic Heart Disorder Sick Sinus Syndrome C0037052 C62244 Sick sinus syndrome Sick Sinus Syndrome A constellation of signs and symptoms which may include syncope, fatigue, dizziness, and alternating periods of bradycardia and atrial tachycardia, which is caused by sinoatrial node dysfunction. Sick Sinus Syndrome Sick_Sinus_Syndrome Cellosaurus Disease or Syndrome A disorder characterized by a dysrhythmia with alternating periods of bradycardia and atrial tachycardia accompanied by syncope, fatigue and dizziness. SSS CTCAE