Aortic intramural hemorrhage: A distinct disease entity with mystery

Aortic intramural hemorrhage (IMH) is one of the disease processes that comprise the spectrum of acute aortic syndrome (AAS) with clinical manifestations and a mortality rate similar to those of classic aortic dissection (AD). However, IMH should be considered as a distinct disease entity rather than a precursor to classic dissection because of differences in their pathology, etiology, natural history, and imaging findings. Multidetector computed tomography (CT) is recommended as the first-line diagnostic imaging modality for IMH, but transesophageal echocardiography (TEE) and magnetic resonance imaging (MRI) are also helpful. There is still debate over the appropriate treatment of IMH. Medical treatment of type B IMH appears effective and safe, while surgical treatment is recommended for type A IMH. Thoracic endovascular aortic repair (TEVAR) is a promising treatment for selected patients, and more clinical evidence needs to be assembled.