Recurrent 12-Month Myocardial Infarction Rates in Patients Discharged with Acute Coronary Syndrome: A Retrospective Analysis from a Regional Referral Centre

Abstract

Background: The Wollongong Hospital is a regional referral centre admitting approximately 900 Acute Coronary Syndromes (ACS) patients per year. Recent advances with potent thienopyridines has reduced recurrent ischaemia rates significantly, which has led to a consensus statement in recent guidelines. Our local policy continues to evolve, however current strategies use aspirin/clopidogrel as the main dual antiplatelet strategy post ACS. Methods: 886 patients presented to Wollongong Hospital with ACS between January and December 2016, most whom were discharged home on an aspirin/clopidogrel regimen. Medical records of these patients were retrospectively reviewed for recurrent myocardial infarction (MI) within one year. Data was collected on traditional coronary artery disease risk factors, previous revascularisation procedures, anti-platelet regimen, time to representation and subsequent requirement for re-vascularisation. Results: Of 886 patients presenting with ACS in 2016, 2.3% (n = 20) represented with an MI within one year. Of these 20 representations, 85% of patients (n = 17) were on aspirin and clopidogrel dual anti-platelet therapy. 95% (n = 19) of patients had prior re-vascularisation procedures, 55% (n = 11) through percutaneous coronary intervention (PCI). 55% (n = 11) of re-presentations were managed medically after angiography, with 45% (n = 9) subsequently requiring bypass or PCI. Conclusion: Recent trials have shown that recurrent ischaemic rates are substantially higher in patients treated with aspirin/clopidogrel than combinations including more potent thienopyridines, however in our cohort re-presentation rates in patients on aspisin/clopidogrel were found to be very low, with a low requirement for subsequent procedural re-vascularisation.