Significant proportion of patients who presented to and released from the Emergency Department (ED)with AMI or unstable angina develop poor outcomes. This is because a large proportion of AMI present atypically.The initial single 12 lead ECG done at an ED is only 50% sensitive for AMI.Serial ECGs have been shown to improve sensitivity by 25%.Because of these limitations, physicians may admit patients with chest pain, liberally. On the other hand only 25-50 % of patients admitted to CCU without AMI are eventually determined to have Acute Coronary Syndrome.