Determining aetiology in dilated cardiomyopathy - does the 'cardiomyopathy blood panel' ameliorate clinical assessment?

BACKGROUND

An increasing number of medical conditions are recognised as causative factors in dilated cardiomyopathy (DCM). Investigating aetiology in DCM is variable in extent among cardiologists and often not performed. We assessed the usefulness of a pre-specified blood panel in identifying an underlying cause in a population of DCM patients.

METHODS

Non-ischaemic DCM patients were identified from sequential new patients with heart failure-reduced ejection fraction (HFrEF) at a regional HF clinic over a 2 year period. Each patient underwent clinical assessment and a blood panel related to causes of DCM. The likely aetiology was documented after initial assessment, and reclassified where relevant when the blood panel results were reviewed.

RESULTS

55 non-ischaemic DCM patients (mean age 63.4 [9.2]yr, 54.5% male) were identified from 259 HFrEF patients. Mean LVEF was 31.3 (4.3)%. After clinical assessment 29 (52.7%) were classified as idiopathic. The commonest specific aetiologies were toxin-mediated (n = 8, 14.5%), genetic (n = 7, 12.7%) and inflammatory (n = 6, 10.9%). Review of blood panels resulted in reclassification in 3 (5.4%) and detection of unrelated medical conditions in 2 (3.6%).

CONCLUSIONS

Despite thorough clinical assessment, DCM remains idiopathic in at least half of cases. Adding an extensive blood panel identifies a specific aetiology in a small proportion of cases.