841 Impact of Timing of Percutaneous Coronary Intervention on Clinical Outcomes in Non-ST-Elevation Myocardial Infarction

International guidelines suggest revascularisation within 72 hours in non-ST-elevation myocardial infarction (NSTEMI). We aimed to examine the impact of timing of percutaneous coronary intervention (PCI) following NSTEMI on clinical outcomes. The Victorian Cardiac Outcomes Registry was established in 2013 as a state-wide clinical quality registry, pooling data from 30 public and private PCI-capable centres. Data were collected on 11,852 PCIs performed for NSTEMI from 2014 to 2018. Patients were divided into three groups by time of symptom onset to PCI (group 1, <24 hours; group 2. 24-72 hours; group 3, >72 hours). Patients undergoing PCI within 24 hours represented 18.4% (n=2,178); 24-72 hours 45.8% (n=5,434); >72 hours 35.8% (n=4,240). Patients waiting longer for PCI were older (62.6±12.2 vs 64.8±12.6 vs 67.0±12.7, p<0.001), more likely to be female (23.1% vs 24.2% vs 26.4%, p=0.007), and have diabetes (18.6% vs 21.1% vs 27.1%, p<0.001). Multivariate logistic regression found that as compared to PCI <24 hours, PCI 24-72 hours and PCI >72 hours of symptom onset were associated with a decreased risk of 30-day mortality (OR 0.55; 95% CI 0.35–0.86, p=0.008 and OR 0.64; 95% CI 0.35–1.01, p=0.053, respectively). Exclusion of 130 patients with cardiogenic shock and out of hospital cardiac arrest tempered this negative association (OR 0.67; 95% CI 0.39–1.14, p=0.14 and OR 0.82; 95% CI 0.49–1.40, p=0.47 respectively). Many Victorian patients undergo PCI outside the recommended 72-hour range following NSTEMI, however, this does not appear to be associated with increased mortality risk.