Aortic Dissection

What is aortic dissection?

Aortic dissection requires immediate care. Without prompt treatment, it could result in sudden death.

The aorta is a large artery that carries blood from the heart to the rest of the body. The aortic wall is three ply, or composed of three layers: the intima (inner), media (middle), and adventitia (outer). An aortic dissection is an intimal tear, meaning that the innermost layer of the aorta breaks, allowing blood to flow, or “dissect,”  into the space between the layers.

Complications of aortic dissection

A tear in your aorta can disrupt normal blood flow, preventing parts of your body from getting the blood they need. Since the aorta supplies blood to your heart, brain, and other organs, this tear can lead to serious issues like a heart attack, stroke, abdominal pain, or even paralysis. Additional complications may occur, such as an aneurysm (a swelling of the blood vessel). In severe cases, the tear can worsen, causing blood to leak into your body, which is known as an aortic rupture.

Aortic dissection types

There are multiple systems of aortic dissection classification. The most common is the Stanford system, which classifies aortic dissections into two types according to the location of the tear.

• Type A: The aorta is shaped like a candy cane or an upside-down J. It goes up from the heart, curves over, and then runs down into the abdomen, finishing near the pelvis. Type A aortic dissections occur closer to the heart, in the top part of the aorta—the curve and the upper section of the straight portion. They may extend into the descending portion as well.
• Type B: The second type, called a type B aortic dissection, occurs in the descending portion of the aorta, farther away from the heart.

When comparing type A vs. type B aortic dissections, type A is more common and more deadly. However, type B aortic dissections are still a medical emergency and require immediate medical and surgical care.

Aortic dissection causes

Weak arteries are a precursor to aortic dissection, but the main cause of aortic dissection is often unknown. In most cases, the artery walls have probably been breaking down over time without causing any symptoms until the tear occurs. This slow breakdown may be due to other conditions, such as stress on the arteries from chronic high blood pressure, or there may be an inherited genetic vulnerability.

Aortic dissection risk factors

While the exact cause of aortic dissection is unclear, there are many known risk factors for the condition, including:

• Age over 50
• Atherosclerosis
• Bicuspid aortic valve and other congenital or genetic heart disease 
• Chronic high blood pressure
• Cocaine use
• Connective tissue disorders like Marfan syndrome, Loeys-Dietz, or Ehlers-Danlos syndrome
• Family history
• Pregnancy with hypertension during or after delivery
• Traumatic injury
• Valve disorders such as aortic valve stenosis or aortic valve regurgitation

Aortic dissection symptoms

The primary symptom of a tear in the aorta is severe, stabbing, or tearing chest pain that may spread to the back and abdomen as the condition worsens. Other warning signs of an aortic dissection include:

• Stroke-like symptoms, including sudden paralsysis
• Anxiety or a feeling of doom
• Cold sweat
• Difficulty breathing
• Fainting
• Pale skin
• Vomiting
• Weak or racing pulse
• Weakness

Aortic dissection diagnosis

Diagnosing aortic dissection begins with a physical exam. A doctor will listen to your heart and examine you. They may hear unusual heart sounds when they listen to your chest with a stethoscope. If the doctor suspects aortic dissection, they may call for imaging tests to confirm their suspicion:

• Chest X-ray: Aortic dissection may not appear clearly on an X-ray, but this quick test can help doctors rule out other conditions or direct further investigation.
• CT scan: CT scans are relatively fast and provide a detailed image of the heart that can confirm the diagnosis. They are the preferred diagnostic tool for aortic dissection.
• Echocardiogram: Ultrasound imaging is quick, non-invasive, and can show the flow of blood in real time, helping to identify aortic dissection.

Other tests that can show the heart in detail, such as MRIs, take too long to be a good choice in an emergency.

Aortic dissection treatment

Less severe cases may be treated with medication until complications develop, but for most aortic dissections, surgery is the only solution. Type A dissections require immediate emergency surgery, while Type B dissections require urgent or emergency surgery, depending on severity.

Surgeons use two main procedures to treat aortic dissection:

• Endovascular repair: This technique is a minimally invasive procedure that uses small incisions to allow the surgeon to insert a tiny tube into your blood vessel and deliver a repair patch called a stent to the site of the tear.
• Replacement: In graft replacement, surgeons replace the damaged portion of the aorta with a synthetic tube.

Sometimes, the surgeon will mix the two types of surgery, especially in two-stage procedures where the tear can't be repaired in a single surgery.

Aortic dissection prognosis

Immediate care is crucial to a good outcome. If you delay treatment until after the aorta ruptures, your chances of survival are less than 50%. For those who get treatment in time, the early mortality rate is still between 9-25%.

Even with successful surgery, life expectancy after an aortic dissection is shorter than for the general population. You'll also need ongoing monitoring for the rest of your life, with regular heart scans every few months.

FAQs about aortic dissection

If you have family members who have had aortic dissection, you may have questions. Remember, If you suspect you have an aortic dissection, get care immediately.