Aims To describe the prevalence of idiopathic and secondary epiretinal membranes (ERM) in a clinical cohort (Australian Heart Eye Study, AHES) and compare to the Blue Mountains Eye Study, and to determine whether associations exist between idiopathic ERM and the extent and severity of coronary artery disease (CAD). Methods The AHES is an observational study that surveyed 1680 participants who presented to a tertiary referral hospital for the evaluation of potential CAD by coronary angiography. Severity and extent of CAD was assessed using three scoring systems: (1) segment/vessel scores, (2) Gensini and (3) extent scores. Two types of ERM were identified: a more severe form, termed ‘preretinal macular fibrosis’ (PMF) in which retinal folds were identified; and a less severe form termed ‘cellophane macular reflex’ (CMR), without visible retinal folds. Results Overall prevalence of ERM was 7.0% (n=115), with CMR and PMF each 3.5%. 72.7% of ERM cases were idiopathic (no secondary cause identified). Prevalence of PMF, but not CMR, was significantly higher than the corresponding age-standardised prevalence in the baseline Blue Mountains Eye Study (p<0.001). There was no significant association between extent and severity of CAD and idiopathic ERM. Conclusions This study suggests that cardiovascular disease (specifically severity and extent of CAD) is not associated with ERM. However, there may be a greater prevalence of severe ERM (PMF) in a high cardiovascular risk cohort relative to a population-based cohort.