Aortic disease is any condition that damages or weakens the aorta, the largest blood vessel in your body. The aorta carries oxygen-rich blood from your heart to every organ and tissue, so when it develops problems, the consequences range from a slow, silent enlargement over decades to a life-threatening emergency that worsens by the hour. Understanding the main forms of aortic disease, what causes them, and how they’re detected can help you recognize risk early.
How the Aorta Works
The aorta runs from the top of your heart, arches over, and extends down through your chest and abdomen before branching into smaller arteries that supply your legs. It delivers not just oxygen but also nutrients and hormones to your internal organs. The wall of the aorta has three distinct layers, each with a specific job. The inner lining lets blood flow smoothly without nutrients being absorbed too early. The middle layer, made of elastic proteins and muscle, stretches and contracts to handle changes in blood flow: widening when your body needs more blood during exercise and narrowing when demand drops. The outer layer anchors the aorta in place and connects it to surrounding nerves and tissue.
This three-layer structure matters because most forms of aortic disease involve damage to one or more of these layers. When the elastic middle layer weakens, the wall can balloon outward. When the inner lining tears, blood can force its way between layers. When fatty deposits build up along the inner wall, blood flow can gradually choke off.
Aortic Aneurysm
An aortic aneurysm is a bulge in the aorta’s wall. It’s formally defined as any section that has expanded to at least 1.5 times its normal diameter. Aneurysms can form in the chest (thoracic aortic aneurysm) or in the abdomen (abdominal aortic aneurysm), and they typically grow slowly over years without causing symptoms. That silence is what makes them dangerous. If an aneurysm ruptures, internal bleeding can be fatal within minutes.
The risk of a serious event rises sharply with size. Once the aorta reaches about 4.0 to 4.4 centimeters in diameter, the chance of dissection (a tear, discussed below) begins climbing. At 4.5 centimeters or above, the risk increases dramatically. People with a bicuspid aortic valve, a common heart valve variation present from birth, face a significantly higher risk of aneurysm, dissection, or sudden death once their aorta reaches the 4.5 to 4.9 centimeter range compared to those whose aorta stays below 4.5 centimeters.
Aortic Dissection
Aortic dissection is a medical emergency. It happens when a tear develops in the aorta’s inner lining, allowing blood to force its way into the middle layer and split the wall lengthwise. This creates a false channel alongside the normal one, and the expanding tear can block blood flow to organs or cause the aorta to rupture.
The hallmark symptom is sudden, severe chest pain that often radiates to the back or abdomen. You may also experience fainting or notice a weak or absent pulse in your legs or feet. The pain is frequently described as the worst the person has ever felt, coming on all at once rather than building gradually.
Dissections are classified by location. A Type A dissection involves the ascending aorta (the section closest to the heart) and carries the highest mortality, around 16% even with treatment. Left untreated, acute Type A dissection kills at a rate of 1% to 2% per hour after symptoms begin, making immediate surgery critical. A Type B dissection is limited to the descending aorta, farther from the heart, and has a lower mortality rate of roughly 5%. A dissection is considered “acute” during the first two weeks after symptoms appear and “chronic” after that point.
Atherosclerosis of the Aorta
Atherosclerosis is the slow buildup of fatty, inflammatory deposits inside the aorta’s wall. It’s driven by lipids (cholesterol and related fats) and involves a chronic immune response that thickens and stiffens the vessel over time. This is the same process that narrows coronary arteries and causes heart attacks, but when it affects the aorta, it can lead to several distinct problems.
Blood clots can form on top of diseased sections of the wall. In severe cases, the aorta can become partially or fully blocked, cutting off blood supply to the legs or organs. At its most advanced stage, atherosclerosis can cause near-complete calcification of the aortic wall, sometimes called a “porcelain” aorta because of the eggshell-like mineral deposits visible on imaging. This late-stage calcification complicates surgery and limits treatment options.
Risk Factors and Genetics
High blood pressure is the single most important modifiable risk factor for aortic disease, particularly dissection. Keeping systolic blood pressure below 120 and diastolic below 80 appears to reduce dissection risk. Smoking is another major contributor, especially for abdominal aortic aneurysms. Age, male sex, and a family history of aortic disease all raise risk further.
Some people are genetically predisposed. Familial thoracic aortic aneurysm and dissection runs in families and can occur without any other visible signs. In other cases, it appears alongside connective tissue disorders like Marfan syndrome or Loeys-Dietz syndrome. People with these conditions may be unusually tall, have stretch marks, have very flexible joints, or have a sunken or protruding chest. If a close relative has had an aortic aneurysm or dissection, screening is often recommended even without symptoms.
Screening and Diagnosis
Most aortic aneurysms produce no symptoms until they rupture or dissect, so screening matters. The U.S. Preventive Services Task Force recommends a one-time ultrasound screening for abdominal aortic aneurysm in men aged 65 to 75 who have ever smoked (defined as 100 or more cigarettes in a lifetime). Men in that age range who have never smoked may still benefit from screening on a case-by-case basis. For women who have never smoked and have no family history, routine screening is not recommended because the condition is rare in that group.
When aortic disease is suspected, CT angiography is generally the first-choice imaging test because it’s fast, widely available, and highly accurate. MRI is an alternative for stable patients and is particularly good at distinguishing between blood that has leaked into the aortic wall and a blood clot sitting on the surface. Ultrasound performed through the esophagus (transesophageal echocardiography) offers similar accuracy but has a blind spot in parts of the upper aorta and requires sedation.
Treatment Options
Small, stable aneurysms are typically monitored with periodic imaging rather than treated surgically. Blood pressure management is central to slowing growth and reducing the risk of dissection. Combination therapy using beta-blockers alongside other blood pressure medications may offer additional protection, though no single drug regimen has been proven in randomized trials to specifically prevent dissection.
When an aneurysm reaches a dangerous size or a dissection occurs, surgery becomes necessary. Two main approaches exist: open surgery, which involves a large incision and direct repair, and endovascular repair, where a reinforcing graft is threaded through a blood vessel in the leg and positioned inside the aorta. For thoracic aneurysms, the endovascular approach (known as TEVAR) has largely become the preferred option. It achieves equal success in fixing the problem but with a survival rate of about 98%, compared to 88% to 94% for open surgery. Recovery is also faster. Most people go home within one day to one week after the endovascular procedure, with less pain, less blood loss, and a lower risk of organ damage.
Endovascular repair does carry its own risks, including the possibility of a leak around the graft (endoleak), graft movement over time, infection, and in rare cases, spinal cord injury leading to leg paralysis. Long-term follow-up imaging is needed to make sure the graft stays in position and continues to seal properly.
Living With Aortic Disease
For people diagnosed with a small aneurysm or a chronic dissection, ongoing management centers on keeping blood pressure low, avoiding heavy lifting or intense straining that spikes pressure in the aorta, and attending regular imaging appointments to track any changes. Quitting smoking, if applicable, is one of the most effective steps to slow disease progression. If you have a genetic condition linked to aortic disease, first-degree family members (parents, siblings, children) are often advised to undergo screening as well, since the same structural weakness in the aortic wall can be inherited without obvious outward signs.