By Rabin Gerrah, MD, cardiothoracic surgeon

Aortic dissection is one of the most serious medical emergencies. Rapid diagnosis and treatment can save a person’s life. A dissection occurs when a tear develops in the inner layer of the aorta. Blood then enters the wall of the artery and forces the layers apart, creating a second passageway. This can interfere with blood flow to important organs or cause the aorta to rupture.

Depending on the location of the dissection, it is classified as Type A or Type B. Type A occurs when the tear involves the ascending part of the aorta, close to the heart, while Type B occurs further down the aorta. Type A is particularly important because it is more common and more deadly, and it requires emergency open-heart surgery. Historical data have often described mortality increasing by approximately 1–2% for every hour that an untreated Type A dissection remains present.

Type B aortic dissection is generally less harmful than Type A, and in most cases, it does not require emergency surgery. In complicated Type B dissections, less invasive procedures, such as percutaneous intervention, may be needed in a less urgent setting. Since Type A dissection is more common and more serious, most of the focus in this article is given to this type of dissection.

What Are the Symptoms of Type A Aortic Dissection?

The common clinical picture often seen in the emergency department is a patient presenting with severe chest or upper back pain, sometimes described as tearing, ripping, or extremely intense pressure. In many cases, patients have no previous knowledge of any aortic disease, and the dissection is the first presentation. Additional symptoms may include fainting or near-fainting, shortness of breath, weakness or numbness, or stroke-like symptoms.

Recognizing these warning signs is important, as every minute matters. It is highly recommended to call emergency services when any of these signs or symptoms appear. When aortic dissection is suspected, an urgent computerized tomography (CT) scan is performed. If a Type A aortic dissection is confirmed, the next step is emergency surgical repair.

Why Does Dissection Happen?

There are multiple reasons for dissection. A tear usually starts in a weakened segment of the aorta, either because of age-related degeneration and atherosclerosis, aortic valve disease, inherited connective tissue diseases or other unknown factors.

In some cases, risk factors such as high blood pressure and smoking affect the aortic wall and create weak or fragile areas. The weakened segment may then expand, creating a larger diameter of the aorta, called an aortic aneurysm. The presence of an aneurysm is a warning sign that the aortic wall has been affected and may progress to dissection. Not all aneurysms progress to dissection, and not all dissections are preceded by an aneurysm.

An aneurysm is often asymptomatic, with no signs or symptoms. It is frequently diagnosed incidentally during imaging performed for other reasons. Historical evidence has shown that the risk of dissection in an aneurysm increases with an aneurysm diameter of 5.5 cm. Therefore, to minimize the risk of dissection, surgical intervention is recommended in these situations. The risk of elective aneurysm repair is significantly lower than that of surgery for a dissection requiring emergency surgery.

New evidence has shown that, in addition to the diameter of the aorta, other factors, such as the length of the aorta, tortuosity, genetic factors and others, also play a role in the development of dissection.

Patients with an aortic aneurysm are routinely evaluated and screened to identify risk factors, and they may undergo surgery to prevent aortic dissection. Once a patient is diagnosed with an aneurysm, they undergo screening and a full workup and are placed under surveillance.

High-risk patients may also undergo genetic testing, readily available at Good Samaritan, to identify genetic factors responsible for aortic aneurysm and dissection. If the test is positive, it can benefit not only the patient by potentially helping prevent dissection, but also close family members, who may otherwise be unaware of their risk for developing a dissection in the future. These measures help minimize the risk of developing a dissection from an aneurysm.

How to Reduce the Risk of Dissection?

Some factors that contribute to the development of dissection can be controlled. Patients with high blood pressure need to monitor their blood pressure and keep it well controlled.

If there is a family history of dissection, aneurysm, or sudden death, simple non-invasive testing can determine the presence of an aneurysm or genetic factors that predispose an individual to aortic dissection. If an aneurysm is diagnosed, depending on its size and other factors, elective surgery can prevent dissection. Small aneurysms need to be monitored for growth over time, and likewise, if they grow rapidly, surgery may be lifesaving.

For patients with an aneurysm, it is recommended to minimize physical activities during which the breath is held, such as weightlifting and pushups. These patients are also instructed to avoid taking some antibiotics, such as ciprofloxacin and levofloxacin, that might weaken the aortic wall and increase the risk of aortic dissection.

At Good Samaritan Regional Medical Center, patients with aortic disease are followed by the cardiology and cardiothoracic surgery teams. Routine follow up and surveillance, as well as genetic testing, are readily available to identify those at high risk and to diagnose any type of aortic disease, all with the goal of preventing aortic dissection.

Despite all these measures, aortic dissections still occur, and emergency surgery can become inevitable. Given the catastrophic consequences of aortic dissection and advancements in clinical knowledge, surgical evaluation and intervention criteria for aortic aneurysms are shifting toward earlier diagnosis, comprehensive workup and proactive surgical repair.

At Good Samaritan, the cardiothoracic surgery team is available 24/7 for emergency surgery for Type A aortic dissection to save lives. Once a Type A aortic dissection is diagnosed, patients are taken immediately to the operating room for repair of the dissection.

Modern and advanced surgical techniques are available and used at Good Samaritan. Surgical repair of Type A aortic dissection entails replacement of the torn segment of the aorta and management of other damage caused by the dissection. Although it is a high-risk procedure, it is the only treatment option for Type A aortic dissection.

Postoperatively, patients stay one to two weeks in the hospital, with four to six weeks of recovery time after discharge.

Read more about aortic dissection or contact your primary care provider if you’d like a referral to Samaritan Cardiology – Corvallis. If you experience aortic dissection symptoms, call 911.

Rabin Gerrah, MD, Samaritan Cardiothoracic Surgery – Corvallis, works at Samaritan through a partnership with Stanford Health Care. Learn about Dr. Gerrah and the life-saving heart, lung and chest procedures he provides at Samaritan.