Chest pain is one of the chief complains of the patients undergoing evaluation in theemergency room. There are different causes of chest pain that vary from benign etiologies,such as the osteomuscular, to high-riskdiseases like the acute coronary syndrome.The differential diagnosis and therapeutic action continue being a challenge to the physician.The myocardial perfusion scan at rest has been used, together with other diagnosticmethods, in the evaluation of these patients. Its use has been considered, especially, regardingthose patients that are stratified as low risk based on clinical, electrocardiographicand cardiac enzymes assays information.We report the case of a patient that was evaluated for chest pain in the emergencyroom where the scan was decisive to ensure the correct diagnosis of the coronary syndromeand adequate patient management.