A 71-year-old woman was admitted with sudden onset of severe chest pain. Computed tomography demonstrated acute type A intramural hematoma with an entry tear in the first part of the descending aorta. The patient refused an operation. Endovascular repair was performed to prevent conversion to a typical dissection of the ascending aorta. At the 1-year follow-up, computed tomography showed total resolution of the intramural hematoma.