U01.07.039 Aortic dissection

Aortic dissection involves a longitudinal intimal tear that forms a false lumen within the aorta. It is often associated with conditions such as hypertension, a bicuspid aortic valve, and inherited connective tissue disorders like Marfan syndrome. This medical emergency can present with symptoms like sudden-onset, tearing chest pain radiating to the back, and may involve markedly unequal blood pressure in the arms.

Pathophysiology

Longitudinal Intimal Tear: The tear leads to the formation of a false lumen, disrupting the normal blood flow through the aorta.
Common Associations:
- Hypertension
- Bicuspid aortic valve
- Inherited connective tissue disorders (e.g., Marfan syndrome)

Clinical Presentation

Chest Pain: Tearing, sudden-onset chest pain radiating to the back.
Unequal Blood Pressure: Markedly unequal blood pressure in the arms may be observed.
Chest X-ray (CXR): May show mediastinal widening, which can be suggestive of aortic dissection.

Complications: Aortic dissection can result in:

Organ ischemia
Aortic rupture
Death

Classification of Aortic Dissection

Aortic dissection is classified into two main types based on the location of the tear and the aortic involvement:

1. Stanford Classification

Type	Involvement	Symptoms & Complications	Treatment
Type A (Proximal)	Ascending aorta (may extend to aortic arch or descending aorta)	May cause acute aortic regurgitation or cardiac tamponade	Surgery
Type B (Distal)	Only descending aorta (below left subclavian artery)	Less likely to cause acute complications, may result in organ ischemia	β-blockers, then vasodilators

2. DeBakey Classification

Type I: Involves the ascending aorta, aortic arch, and descending aorta.
Type II: Involves only the ascending aorta.
Type III: Involves only the descending aorta (commonly seen in Type B Stanford).

Treatment Strategies

Stanford Type A (Proximal Dissection): Requires surgical intervention to repair the dissection and prevent further complications like aortic rupture or cardiac tamponade.
Stanford Type B (Distal Dissection): Initial management involves β-blockers to control blood pressure, followed by vasodilators to reduce stress on the aorta.

Key Points to Remember

Symptoms: Sudden, tearing chest pain, unequal blood pressure in arms, and mediastinal widening on CXR.
Types of Dissection: Stanford A (proximal) requires surgery, while Stanford B (distal) is treated initially with β-blockers and vasodilators.
Complications: Includes rupture, ischemia, and death.

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