disease has basis in dysfunction of disease has feature Arrhythmia sinoatrial node disorder sick sinus syndrome https://www.malacards.org/card/sick_sinus_syndrome SCTID:36083008 MEDGEN:20749 NCIT:C62244 MONDO:0001823 icd11.foundation:1682594333 MESH:D012804 NANDO:2100043 ICD10CM:I49.5 SSS UMLS:C0037052 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. NANDO:2200212 DOID:13884 syndromic disease sinoatrial node