Objective: To describe the contemporary management and outcomes of patients presenting with ST-segment-elevation myocardial infarction (STEMI) in Australia.
Design, participants and setting: Observational analysis of data for patients who presented with suspected STEMI and enrolled in the Australian Acute Coronary Syndrome Prospective Audit from 1 November 2005 to 31 July 2007.
Main outcome measures: Factors associated with use of reperfusion therapy and timely use of reperfusion therapy, and the effects of reperfusion on mortality.
Results: In total, 755 patients had suspected STEMI. Median time to presentation was 105 minutes (IQR, 60-235 minutes). Reperfusion therapy was used in 66.9% of patients (505/755), and timely reperfusion therapy in 23.1% (174/755). Thombolysis was administered in 39.2% of those who received reperfusion therapy (198/505), while 60.8% (307/505) received primary percutaneous intervention. Cardiac arrest (OR, 2.83; P = 0.001) and treatment under the auspices of a cardiology unit (OR, 2.14; P = 0.02) were associated with use of reperfusion therapy. A normal electrocardiogram on presentation (OR, 0.42; P = 0.01), left bundle branch block (OR, 0.18; P = 0.001), acute pulmonary oedema (OR, 0.34; P < 0.01), history of diabetes (OR, 0.54; P < 0.01), and previous lesion on angiogram of > 50% (OR, 0.51; P = 0.001) were associated with not using reperfusion. In hospital mortality was 4.0% (30/755), mortality at 30 days was 4.8% (36/755), and mortality at 1 year was 7.8% (59/755). Receiving reperfusion therapy of any kind was associated with decreased 12-month mortality (hazard ratio [HR], 0.44; 95% CI, 0.25-0.78; P < 0.01). Timely reperfusion was associated with a reduction in mortality of 78% (HR, 0.22; P = 0.04). There were no significant differences in early and late mortality in rural patients compared with metropolitan patients (P = 0.66).
Conclusion: Timely reperfusion, not the modality of reperfusion, was associated with significant outcome benefits. Australian use of timely or any reperfusion remains poor and incomplete.