 This study aims to investigate the effect of early CTCA in patients with suspected or confirmed Acute Coronary Syndrome ACS presenting to the Emergency Department ED or Medical Assessment Unit MAU, upon interventions, event rates and health care costs in a pragmatic clinical trial and economic evaluation up to 1 year after the trial intervention. The primary objective will be to investigate the effect of the intervention on the proportion of patients with all-cause death or recurrent non-fatal type 1 or type 4b myocardial infarction MI at one year. 