Ascending Aorta

The ascending aorta is the beginning portion of the largest blood vessel in your body. It carries oxygen-rich blood from your heart to the rest of your aorta. Your two main coronary arteries branch off of the ascending aorta.


What is the ascending aorta?

The ascending aorta is the first part of the aorta, which is the largest blood vessel in your body. It comes out of your heart and pumps blood through the aortic arch and into the descending aorta. The aorta plays an essential role as the main “pipe” supplying blood to your entire body. The ascending aorta is the first portion of this pipe as it exits your heart.


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What is the purpose of the ascending aorta?

The aorta carries oxygenated blood from the left ventricle (one of your heart’s four chambers) to the rest of your body. The ascending aorta is the first part closest to your heart. This portion has two small branches. These are the major coronary arteries that supply oxygen-rich blood to the heart muscle.

The aorta is the pipe that helps oxygenated blood get from your heart to every part of your body — from your brain to your digestive tract.


Where is the ascending aorta located?

The ascending aorta sits atop the left ventricle on the left side of your heart. It extends up and over the heart. It’s located in your chest right behind the “breastbone” (sternum).


What does the ascending aorta look like?

The entire aorta looks a bit like a cane. The ascending aorta is the first and shortest part of the aorta. It moves in an upward direction until it becomes the aortic arch, which would be the cane’s handle. From the arch, the aorta moves downward through the chest and abdomen.

What is the normal size of the ascending aorta?

The ascending aorta is about 5 to 8 centimeters (or close to 2 to 3 inches) long. It’s about 3 to 4 centimeters wide. The aorta gradually narrows as it moves down through the chest.


What are the parts of the ascending aorta?

The entire aorta divides into two parts: the thoracic aorta and the abdominal aorta. The ascending aorta, along with the aortic arch and the descending aorta, makes up the thoracic aorta.

The ascending aorta begins right after the left ventricle of the heart and contains the aortic heart valve, which is a flap that opens and closes to allow blood to enter the aorta from the left ventricle. The ascending aorta ends right before the brachiocephalic artery, which is the first branch off the aortic arch.

The ascending aorta has two parts:

  • Aortic root: The root is the first part of the ascending aorta, closest to the aortic valve. It includes the aortic sinuses, which are bulb-shaped cavities from which the right and left coronary arteries arise. The root also contains the sinotubular junction (STJ), which is where the ascending aorta takes on its normal tube shape.
  • Tubular ascending aorta: The second section of the aorta begins after the STJ and extends to the aortic arch. This part of the ascending aorta doesn’t have any branches.

Like the rest of the aorta, the ascending aorta has three layers of tissue:

  • Tunica intima: The innermost layer of the aortic wall.
  • Media: The middle layer of the aortic wall contains elastic fibers. Over time, these fibers can become stiff and weaken the wall.
  • Adventitia: The outermost layer of the aortic wall contains tiny vessels.

Conditions and Disorders

What conditions and disorders affect the ascending aorta?

The most common problems that can develop in the ascending aorta include:

  • Aortic aneurysms: An aneurysm is a bulge in an artery, resulting from a weak spot in the vessel’s wall. More than 50% of all thoracic aortic aneurysms (TAAs) occur in the ascending aorta. They can occur in the aortic root or the tubular ascending aorta. Aortic aneurysms are life-threatening conditions. They can cause tears between the layers of the blood vessel walls, called aortic dissections. Or they can rupture completely and lead to severe internal bleeding.
  • Aortic valve stenosis: Though not part of the ascending aorta, the aortic valve is attached to the inside of the ascending aortic wall. Aortic stenosis occurs when the aortic valve that connects the aortic root and left ventricle gets too narrow. Your heart has to work harder to get blood into your aorta. This might cause an enlarged heart muscle.
  • Aortic valve regurgitation: If the aortic valve doesn’t close completely, blood might leak backward into your left ventricle instead of only flowing forwards into your aorta. Your heart has to pump more blood than normal, which might cause the heart to become weak over time. A dilated ascending aorta can be the cause of aortic valve regurgitation.
  • Bicuspid aortic valve (BAV): Some people are born with two flaps at their aortic valve instead of three. These valves can be associated with ascending aortic aneurysms. BAV often leads to aortic stenosis, aortic regurgitation or both.
  • Connective tissue diseases: Connective tissue disorders include diseases like Marfan syndrome, Loeys-Dietz syndrome and Ehlers-Danos syndrome.
  • Inflammatory disorders: These include conditions like giant cell arteritis and penetrating atherosclerotic ulcers.


How can I keep my ascending aorta healthy?

There are a variety of ways you can improve the health of your heart:

Additional Common Questions

When should I call my doctor?

If you’ve been diagnosed with an ascending aortic condition or any heart problem, contact your doctor right away if you notice any new symptoms or your existing symptoms get worse.

Seek immediate medical attention if you experience any of the following symptoms, as they could be signs of a ruptured aneurysm:

  • Dizziness or fainting.
  • Fast heartbeat.
  • Severe pain in your upper back or chest.
  • Shortness of breath.

A note from Cleveland Clinic

The ascending aorta is the first section of your aorta, the largest blood vessel in your body. It’s attached to your heart and plays an essential role in helping your heart deliver oxygen-rich blood to your entire body. Problems in the ascending aorta, such as ruptured aneurysms, can be life-threatening. If you have a family history of heart problems, or you’re over the age of 65, talk to your healthcare provider about reducing your risk for problems in your ascending aorta.

Medically Reviewed

Last reviewed on 10/20/2021.

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