Heart - Cardiology & Cardiovascular Surgery

Aortic Aneurysms: Types and Causes

At Mount Sinai Heart, we have experience in diagnosing and treating all types of aortic aneurysms. We often use open-heart surgery, and when appropriate, we perform minimally invasive procedures.

Bicuspid Aortic Valve Disorder

Most heart valves have three leaflets that open and close to regulate blood flow, to make sure the blood goes where it is needed and doesn’t go where it shouldn’t. About 2 percent of people have only two leaflets, which we call a bicuspid valve. This condition often leads to complications that require medical intervention.

Typically, the valve either becomes narrow (called stenosis) or unable to close tightly (called incompetent or regurgitant), or a combination of the two. If you have a bicuspid valve, you are also at risk of developing an aneurysm of the ascending aorta or an acute aortic dissection. You need careful follow-up by your cardiologist, with annual echocardiograms and either computed tomography or magnetic resonance imaging scans.

Degenerative Aortic Aneurysms 

Degenerative aortic aneurysms are the most common type of aneurysms. They occur when the connective tissue and muscular layer of the aorta weakens and gets thinner, which increases the chances that it will break (called rupture) or that the layers of tissue will tear (called dissection). Often, degenerative aortic aneurysms happen in the abdomen or the descending thoracic aorta. Most people with degenerative aortic aneurysms don’t have symptoms, so we typically find the disease when doing a chest X-ray or computerized tomography scan for another cardiac concern.

Marfan Syndrome and Connective Tissue Disorders

Marfan syndrome is a rare genetic mutation that affects your body’s connective tissue and other organs. It can lead to aortic enlargement, or an expansion of the aorta, which can be life threatening. Usually, Marfan patients get aneurysms at the level of the aortic root, though they can also develop in the descending thoracic aorta or the abdomen. Since connective tissue gives the aortic wall its strength, a weakened aortic wall can lead to an aneurysm, which can tear or rupture. 

Penetrating Atherosclerotic Ulceration

Penetrating atherosclerotic ulceration occurs when cholesterol plaque develops in the arteries, causing them to enlarge or develop holes in the aortic wall. It can also allow blood to leak outside the artery and pool into a hematoma, or clot, which can cause pain or swelling. This syndrome typically happens in older patients and often affects the descending thoracic aorta, though it can also develop in the aorta. When this occurs, you often experience chest pain. Penetrating atherosclerotic ulceration can also arise without symptoms.


Usually caused by injury to the aortic wall, a pseudoaneurysm (also known as a false aneurysm) causes blood clots outside the outer layer of the aortic wall, not within the layers of the wall. You may experience pain as the expanded aorta presses against your other organs. We diagnose this condition with a computerized tomography or magnetic resonance imaging scan.

Thoracic Aortic Aneurysms 

Thoracic aortic aneurysms occur in the arteries that go through your chest area. This is a rare disease which affects more men than women. It is linked to chronic obstructive pulmonary disease, genetics, smoking, and high blood pressure. Not all thoracic aortic aneurysms have the same implications and therefore treatment options vary. We worry more about fast-growing thoracic aortic aneurysms than slower-growing ones, as large aortic aneurysms can rupture. We treat this disease with monitoring or surgery. 

Trauma-Induced Aneurysm

A trauma-induced aneurysm is typically caused by a motor vehicle accident or other injury. We think about whiplash as a non-serious condition resulting in neck and back pain that goes away over the course of a few days/weeks. But it can also cause your aorta to tear or break because of the pressure that the injury places on your aortic wall, typically in the thoracic aorta.  We usually treata trauma-induced aneurysm surgically.