We report a 20-year-old woman with blunt chest trauma because of a motor vehicle injury who has traumatic asphyxia and hypotension. The diagnosis of blunt cardiac injury was put by using dual-energy computed tomography in the emergency department because other laboratory and imaging modalities were useless. After hospitalization in intensive care unit, she was treated with supportive and antiedema therapy. The patient was extubated on the fifth day and discharged on the ninth day without any sequel. Coexistence of traumatic asphyxia with blunt cardiac injury is rare. Several imaging techniques such as transthoracic and transesophageal echocardiography, contrast-enhanced multislice thorax computed tomography or initial electrocardiogram, and troponin I levels are used to detect the myocardial damage, but diagnostic capability is low. Dual-energy computed tomography is a promising new technology with the ability of defining blunt cardiac injuries and may have an indication in the emergency setting in patients with hemodynamic instability to rule in traumatic cardiac complications especially when electrocardiogram and transthoracic echocardiography are useless in the emergency department.