Pulmonary embolism (PE) is a potentially lethal condition that presents in patients with chest pain or shortness of breath. Although electrocardiograms (ECGs) typically demonstrate abnormalities associated with PE, ST-segment elevation, which can indicate anteroseptal acute myocardial infarction (AMI), has-on rare occasions-been noted on ECGs of patients with acute PE. The current report documents the case of a 57-year-old man who presented to the emergency department with chest pain. Findings from an ECG suggested anteroseptal AMI; however, cardiac catheterization indicated that the patient did not have critical ischemic heart disease. On further examination, the patient was found to have a massive bilateral PE. The present report emphasizes that physicians must investigate PE in all patients presenting with chest pain, dyspnea, or both, even in the face of ECG changes that are suggestive of a cardiac etiology. A brief discussion of the current theories of ST-segment elevation in the setting of PE is also included.