Aorta is the major blood vessel in the humans that feed blood to the body. A person can develop a thoracic aortic aneurysm (TAA) if the upper part of their aorta is weak. An aneurysm can lead to tearing in the arterial wall which can cause life-threatening bleeding. The chances of a small and slow-growing TAA rupturing are less compared to large, fast-growing aneurysms which may rupture anytime. The occurrence of TAA is rare and is found in 6 – 10 per every 100,000 people. 20% of these cases are linked to family history and the rest of it to age, smoking and high blood pressure. Surgery is offered when the risk of rupture is greater than the risk of the operation. The procedure is known as thoracic aortic aneurysm repair.
- Hardening of the arteries (atherosclerosis)
Due to a plaque build-up, the artery wall becomes less flexible causing them to weaken and bulge. Aso because of high BP and cholesterol levels, the arteries start to harden up which is more commonly seen in older people.
- Genetic Conditions
In younger people, TAA has been linked to genetic causes. People born with Marfan syndrome – a genetic condition that affects the connective tissues in the body, are at a high risk of suffering from this disease. People with Marfan syndrome have a weak aortic wall making them susceptible to an aneurysm. Besides Marfan syndrome, Ehlers-Danlos, Loeys-Dietz and Turner syndromes, and other family-related disorders can cause an aortic aneurysm. Ehlers-Danlos syndrome causes the skin, joints and connective tissue to be fragile and makes the skin stretch easily.
- Other medical conditions
Inflammatory conditions, such as giant cell arteritis and Takayasu arteritis, may cause TAA.
- Problems with the heart’s aortic valve
People with problems in the blood flow valve of the heart are also at an increased risk of TAA. This is mainly true for people who were born with a bicuspid aortic valve, meaning the aortic valve has only two cusps instead of three.
- Untreated infection
Although rare, untreated infections like syphilis or salmonella can also cause a TAA.
- Traumatic injury
Rarely, some people who are injured in falls or motor vehicle crashes develop TAA.
Usually, TAA develops and expands slowly over time. In the majority of the cases, symptoms are discovered while being tested for other reasons. In some of the rare cases, if the aneurysm grows large enough, it can compress the nearby areas. The person’s voice may become hoarse or they may have difficulty swallowing. In rarer circumstances, the aneurysm can cause pain, usually a tearing or sharp, severe pain between the shoulder blades. Usually, the pain tends to occur when an aneurysm grows quickly or ruptures, or if the aorta wall develops a tear.
There are different ways in which a TAA can be identified. Most of the cases the aneurysms are identified when the patient is being tested for other reasons. A thoracic aortic aneurysm can be detected on a routine X-ray. Advanced imaging tests like CT scan, MRI, echocardiogram, genetic testings can provide a more accurate diagnosis about the TAA.
The goal of treatment is to prevent the aneurysm from growing, and intervening before it dissects or ruptures. Generally, the treatment options are medication, monitoring or intervention, which usually involves surgery. The doctors decide based on the size of the aortic aneurysm and how fast it’s growing. Constant monitoring is a standard for smaller aneurysms that do not require surgery. It is recommended to visit a vascular surgeon once a year or in 6 months, depending on the size of the aneurysm – for a CT scan or MRI to check its status and growth.
Thoracic aortic aneurysm repair which is a conventional surgery is done under full anaesthesia. Through an incision along the side of the chest, using special tools, the vascular surgeon stops blood flow in the aorta above and below the aneurysm. An artificial graft is used to replace the section of the aorta and is sewed with stitches to close the incision. Usually, the patients stay for 7 – 10 days in the hospital before being discharged.
Nowadays a much less invasive approach of endovascular treatment is used to treat this condition. The aneurysm is repaired by passing a plastic graft into the damaged area of the blood vessel- this is achieved through small cuts or punctures in the upper thigh. The procedure is often done with the patient awake. Thoracic aortic endograft repair (TEVAR) achieves almost the same results as open surgery but with much less damage to the body.
Unfortunately, not all aneurysms are of a suitable shape and some patients will need the traditional open surgery or a more modern method that combines TEVAR with debranching- a hybrid procedure.
- Maintaining good overall health is always beneficial.
- If aneurysm runs in family all-male members must get a screening evaluation
- Always maintain blood pressure levels.
- Abstain from smoking. Seek help with smoke cessation programs from the doctors.
Dr. Robbie George | Chief of Vascular & Endovascular Surgery | Mazumdar Shaw Medical Center, Bommasandra, Bangalore