37 Aortic Dissection

Aortic Dissection

Pathogenesis

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• intima right next to blood

• can spread distally to abdomen or proximally toward heart

• type A mortality very high, surgery to correct, replace with graft

• HTN drives blood into false lumen

Symptoms

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• stretch aortic valve: regurge

• wraps around aorta

• dissection obstructs blood flow to one arm

• mediastinum: 1

Diagnosis

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• clots form after blood get into dissection

• contrast CT

• top: aorta

• dissection flap: piece of tissue in middle. Blood broken through layers of aorta and separated aorta

• True lumen: bigger one

• false lumen: space inside flap

• type A:

• type B:

Risks

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• aortic dissection requires tension on wall and weakness of media layer

• HTN leads to thick vasa vasorum

• Marfans, Eherlos Danlos

• aortopathy: abnormal aorta, in bicuspiad aortic valve and marfan

Complications

Aortic Aneurysms

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• true aneurysms

Thoracic

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• often identified by screening

Abdominal

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• almost always occur in association with atherosclerosis

• above bifurcation, below renal arteries

Aortic Rupture

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• tear through all 3 layers

• elasticity in proximal portion

• rigid in descending portion