University of Edinburgh, University Hospitals Plymouth NHS Trust, University Hospitals Plymouth NHS Trust - Emergency Department, University of Sheffield, University of Edinburgh, Royal Infirmary of Edinburgh - Emergency Medicine Research Group Edinburgh (EMERGE), University of Sheffield, University of Southampton - Coronary Research Group, Royal Berkshire NHS Foundation Trust - Emergency Department, Milton Keynes University Hospital NHS Foundation Trust, Torbay and South Devon NHS Foundation Trust, University of Edinburgh, University of Sheffield, University of Edinburgh, University of Edinburgh - Centre for Cardiovascular Science and Independent

University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, University of Southampton - University Hospital Southampton NHS Foundation Trust, Keele University, University of Southampton - University Hospital Southampton NHS Foundation Trust, Keele University and University of Southampton - Coronary Research Group

affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Royal Free Hospital, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, University of Southampton - Coronary Research Group, affiliation not provided to SSRN, affiliation not provided to SSRN, Leeds General Infirmary, affiliation not provided to SSRN, affiliation not provided to SSRN, Medical University of Gdańsk, University of Gdansk, affiliation not provided to SSRN, University of Bristol - Bristol Heart Institute, University of Minnesota, affiliation not provided to SSRN, affiliation not provided to SSRN, London Ambulance Service NHS Trust, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, King’s College London - Institute of Psychiatry, Psychology and Neuroscience and affiliation not provided to SSRN