reduce door to balloon (DTB) time in STEMI. Shorter DTB times are associated with reduced mortality. The main barrier to implementing ED CCL activation is concern of inappropriate activation of the CCL. Aim:Tocompare falsepositive ratesof suspectedSTEMI patients undergoing emergency coronary angiography by cardiology verses senior ED activation of the CCL. Methods: All patients undergoing emergency cardiac catheterisation forSTEMI from2007 to2009wereanalysed. Falsepositive rateswere comparedbefore andafter implementing a protocol enabling independent ED activation of the CCL (2007–2008 vs. 2009). Some patient characteristics required ED to communicate with cardiology prior to CCL activation (elderly, borderline ECG changes, out of hospital arrest, LBBB, significant co-morbidities). Patient files, ECGs, coronary angiograms and left ventriculograms were reviewed in all patients undergoing emergency angiography without percutaneous coronary intervention to determine diagnosis, management and cause of the false positive cases. Results: Cardiology 2008–2009 (n= 150) ED 2009 (n= 84) Primary PCI 118 (79%) 70(83%) Medical management 11 (7%) 4 (5%) Surgery 3 (2%) 1 (1) False positive 18 (12%) 9 (11%) (NS) Causes of false positives: Chest pain of unclear cause with either early repolarisation of ST segments or LBBB (63%, 7/27). Takotsubo cardiomyopathy (22%, 6/27), myo/pericarditis (11%, 3/27) and pulmonary embolism (5%, 1/27). Conclusion: False positive rates in patients undergoing emergency angiography for suspected STEMI is not increasedwithacontrolledsystemofemergencyphysician activation of the cardiac catheterisation laboratory. doi:10.1016/j.hlc.2010.06.975