This study aims to evaluate the prognostic value of the anion gap in predicting mortality among patients with acute pulmonary embolism. Researchers will collect information based on hospital registry as secondary data of in patient who had diagnosed as acute pulmonary embolism by using computed tomography scan (CT scan). The data consist of demographic data, clinical presentation, laboratory, and CT scan were collected from hospital registry by reviewing medical record. Then, the data was analyzed by using IBM SPSS Statistics v26.