Down’s syndrome, also known as trisomy 21, is a common chromosomal abnormality associated with multiple co-morbidities, premature ageing and decreased life expectancy. We present four cases of individuals with Down’s syndrome without congenital heart disease who presented with syncope and subsequently were found to have severe sinoatrial node disease, all requiring permanent pacemaker implantation. An association between the conditions has not previously been described and we postulate a possible increased frequency of sinoatrial node disease in adults with Down’s syndrome. In addition, in each case there was a considerable delay in reaching the diagnosis of sinoatrial node disease; this was partly due to alternative differential diagnoses (particularly neurological) being considered first, partly due to difficulties in obtaining an accurate history of the syncopal events and partly due to decreased co-operation by the patients with regards to investigation of the underlying aetiology of their events.
Source: Kennedy et al.