The aorta is the largest artery in the body. It is the main blood vessel that carries blood from the heart to the rest of the body. It extends from the heart into the chest, down to the abdomen and into the pelvis. From there, it then goes down to form the main blood supply to the legs. During its course, the aorta gives off vital branches that form the key arterial blood supply to vital organs such as the liver, stomach, intestines and kidneys.
An Aortic Aneurysm (AA) develops when the wall of the aorta weakens and begins to bulge outwards like a balloon.
There are several regions where an aortic aneurysm may develop:
In its early stages, when an AA is small in size, it does not pose an immediate health risk. However, if the AA continues to grow, the walls of the aorta or its lower branches can become thin and lose their ability to stretch. The weakened sections of the wall may become unable to support the force and pressure of blood flow. Such an aneurysm could burst, causing severe internal bleeding and death.
Patients are advised to undergo screening if they belong to the following risk factor groups:
Diagnosis is based on clinical examination where an aneurysm can be felt as a throbbing mass in the abdomen. An ultrasound scan or CT scan is recommended for confirmation of an aneurysm
There are two types of treatment for AA:
After the AA has been treated, all patients should have regular follow-ups for the rest of their life. This is because the disease can continue to develop in other parts of the aorta that were previously aneurysm-free. It is not uncommon for a patient with an abdominal aneurysm to then develop a thoracic aneurysm and vice versa. This is especially so if the patient still has persistent risk factors such as smoking and hypertension.
Follow-up post aneurysm repair requires repeat ultrasound scans and CT scans to be done at regular intervals (6 monthly at first and then annually). This is particularly important for patients who have undergone the EVAR procedure and the scans are done to detect leaks around the covered stent graft.
An aortic dissection occurs when there is a tear in the wall of the aorta, resulting in blood flowing in between the muscle layers of the aorta. As a result, the aorta is divided into two openings instead of one. An aortic dissection can disrupt flow into the artery branches and organs supplied by the aorta, including the intestines, kidneys and legs, ultimately causing organ failure.
At-risk groups include:
A contrast CT scan of the chest and abdomen is the best way to diagnose an aortic dissection. It will also reveal where the initial tear in the aortic wall is, the extent of the dissection (which parts of the aorta is involved) and the affected organs/blood supply. This will give the doctors an idea of the best way to treat the dissection
The immediate priority will be to control the elevated blood pressure so that the dissection does not worsen.
The next step is either open surgery to repair the tear of the aortic wall or minimally invasive EVAR – the insertion of a stent-graft through the groin arteries.
Kandola, A. (2020, May 27). Abdominal aortic aneurysm: Screening, treatment, and symptoms. Retrieved January 25, 2022, from https://www.medicalnewstoday.com/articles/abdominal-aortic-aneurysm