Introduction : Aortic intramural hematoma (IMH) is one of the variant of aortic dissection, characterized by absence of a detectable intimal tear. Aortic IMH is considered a precursor to classic aortic dissection and accounted for 5 to 13 percent of patients with symptoms consistent with an aortic dissection and is most often associated with long standing hypertension.

Case report : This is a 52 y/o man who had 15 pack-years history of cigarette smoking and uncontrolled hypertension for about 5 years of duration.. Two hours prior to ED visit, while packing betel nuts, he was suffering from sudden onset of severe tearing Lt chest pain, with radiation to the back, associated with cold sweating and dyspnoea. The chest pain was not relieved by resting or worse with respiration. Vital signs on arrival were TPR-36.5/66/20, BP215/135mmHg. Physical examinations were unremarkable except cold and wet upper limbs and trunk.. Laboratory results were WBC:10390/mm³, Hb:14.6 g/dl , Neutrophils:83.4%, Hct:46.8%, Platelet 212,000/mm³, CK 275U/L, CK-MB 4.6U/L, Troponin-I 0.01ng/dl. CXR and ECG were also unremarkable. For his typical chest pain, chest CT was arranged and disclosed isolated intra luminal filling defect of aortic arch. and was admitted to ICU and SBP was controlled < 110mmHg with beta blocker. As chest pain went away and well controlled BP, he was transferred to ordinary ward for further care on the 2^nd hospitalization day. On 3^rd day of hospitalization, he suffered from severe right flank pain with cold sweating, The chest and abdominal CT were repeated. Which revealed progression of intramural hematoma of aortic arch into severe acute aortic dissection (Stanford type B).

Discussion : Penetrating ulceration of an atherosclerotic plaque often complicates an aortic intramural hematoma and can also lead to aortic dissection or perforation. Early diagnosis before dissection is a great challenge to the physician and of course, would be very much beneficial to the patient.