Intramural Hematoma

How to Cite This Chapter: Szalay D, Frołow M, Leśniak W. Intramural Hematoma. McMaster Textbook of Internal Medicine. Kraków: Medycyna Praktyczna. Accessed July 15, 2024.
Last Updated: December 9, 2021
Last Reviewed: December 9, 2021
Chapter Information

Definition, Etiology, PathogenesisTop

Aortic intramural hematoma (IMH) is a type of acute aortic syndrome in which blood accumulates in the media of the aortic wall but no false lumen has developed and intimal tear is absent. Just like acute aortic dissection, IMH may be divided into type A or type B and generally presents as chest or back pain without evidence of rupture or malperfusion.

The greatest concern with intramural hematomas is that most clinicians believe they are part of the same spectrum of disease as dissections and as such carry similar risks in case of progression.

Natural HistoryTop

In 30% to 40% of patients with IMH type A, aortic dissection occurs (the risk is highest within 8 days of symptom onset).


Computed tomography (CT) and magnetic resonance imaging (MRI) are the key diagnostic studies used to diagnose and classify IMH.


1. Medical treatment: Control of pain and blood pressure. Repeat imaging studies.

2. Invasive treatment:

1) In IMH type A coexisting with a pericardial effusion, periaortic hematoma, or large aneurysm, start emergency surgical treatment.

2) In other cases of IMH type A, urgent surgical treatment is necessary (within <24 hours of diagnosis), although in many elderly patients and those with significant comorbidities initial medical treatment may be justified (provided the aortic diameter is ≤50 mm and thickness of the intramural hematoma is <11 mm).

3) In IMH type B, medical management is the primary treatment but invasive treatment (usually endovascular stenting) is indicated in case of complications.


Recurrent pain, hematoma expansion, periaortic hematoma, or disruption of the intima.

Risk factors for complications of IMH: Persistent or recurrent pain despite aggressive medical treatment, difficult blood pressure control, ascending aortic involvement, maximum aortic diameter ≥50 mm, progressive maximum aortic wall thickness (>11 mm), enlarging aortic diameter, recurrent pleural effusion, unstable atherosclerotic plaque (penetrating ulcer or ulcer-like projection) secondary to localized dissections in the involved segment, organ ischemia (brain, myocardium, bowels, kidneys).

We would love to hear from you

Comments, mistakes, suggestions?

We use cookies to ensure you get the best browsing experience on our website. Refer to our Cookies Information and Privacy Policy for more details.