Diagnosis of aortic intramural haematoma.

A ortic intramural haematoma (IMH), a variant form of classic aortic dissection, has been accepted as an increasingly recognised and potentially fatal entity of acute aortic syndrome (AAS). In classic aortic dissection, flow communication occurs through a demonstrable primary intimal tear and blood flow propagation creates a so called ‘‘double channel aorta’’ with a true and false lumen. In IMH, it is believed that haemorrhage occurs within the aortic wall in the absence of initial intimal disruption. Thus, conventional aortography, which is useful for detection of intimal flap or double channel aorta in classic aortic dissection, failed to identify this disease entity and antemortem diagnosis of IMH was difficult. With recent advances and successful clinical introduction of various non-invasive imaging modalities for aortic pathology, such as contrast enhanced x ray computed tomography (CT), magnetic resonance imaging (MRI), and transoesophageal echocardiography (TOE), the clinical significance of IMH can be truly estimated. In this presentation, I would like to focus on the characteristic imaging features of IMH by these modalities and difficult scenarios for diagnosis.