What is an aortic aneurysm?
The aorta is the largest artery in the human body, it starts from the heart (from the left ventricle specifically), passes through the chest and abdomen and reaches the level of the navel, where it is divided into the so-called iliac arteries (right and left). Its average normal diameter in the chest (thoracic aorta) is up to 28 mm, while in the abdomen (abdominal aorta) around 20 mm. When the diameter of a vessel exceeds 1.5 times the maximum normal diameter, then we are talking about an aneurysm. This occurs when the diameter of the thoracic aorta exceeds 4.5 centimeters (45 mm) and the abdominal aorta exceeds 3 centimeters (30 mm).
The majority of aneurysms are located in the abdominal aorta. These in turn are distinguished into suprarenal when they begin more centrally than the origin of the renal arteries, pararenal when they begin just below the renal arteries, and infrarenal when they begin below the origin of the renal arteries and between them and the aneurysm there is a section of healthy aorta. The latter constitute 95% of abdominal aortic aneurysms.
What are the risk factors for aortic aneurysm?
Aortic aneurysm is more common in men than in women. Also, the risk of its occurrence increases with age. It is sufficient to mention that in men aged 65-80 years the percentage of those who have an abdominal aortic aneurysm is 2-5%. In women of the same age the percentage is up to 1%. Other important risk factors are smoking, poorly controlled arterial hypertension and a of aneurysm in first-degree relatives. It is also important to mention that patients with peripheral arterial disease or heart disease have an increased risk of developing an aortic aneurysm.
What are the symptoms of aortic aneurysms?
are Aortic aneurysms mostly asymptomatic and are most often discovered incidentally when tests are performed for other reasons. Unfortunately, sometimes the aneurysm is noticed when it ruptures, which can often be fatal for the patient. For this reason, simple ultrasound screening is recommended for people over 60 years of age.
Among the symptoms that patients may experience are intense abdominal palpitations, as well as pain abdominal or lower back “blue toe syndrome” where parts of the toes become blue and are accompanied by pain. An extremely rare type of aneurysm is the inflammatory aneurysm of the abdominal aorta, which is characterized by retroperitoneal fibrosis and can cause obstruction of the ureters with hydronephrosis and pain.
When the aneurysm ruptures, it is called an aortic aneurysm rupture and the symptoms are usually dramatic with sharp pain in the chest, back, waist or abdomen, depending on where the aneurysm is located. Severe bleeding can lead to a rapid drop in blood pressure and increased heart rate, loss of consciousness and even circulatory shock .A ruptured aneurysm is associated with high mortality.
How are aortic aneurysms diagnosed?
The diagnosis and monitoring of abdominal aortic aneurysms is done with a simple ultrasound. In case the diagnosis is made, then the examination can be accompanied by a color ultrasound arteriography, the well-known triplex with examination of the iliac arteries. When the prospect of determining a treatment strategy arises, it is necessary to visualize the entire aorta, which is done with axial or magnetic angiography. This examination is also important for excluding an accompanying thoracic aneurysm. Thoracic angiography is also performed when the cardiac ultrasound expresses the suspicion of the existence of a thoracic aortic aneurysm. Finally, ultrasound examination of the popliteal arteries, the arteries that pass behind the knee, is also important, because it is known that approximately 50% of patients with aortic aneurysms also have some type of aneurysm in these arteries. The importance of identifying popliteal artery aneurysms does not arise from the risk of rupture, but from thrombotic occlusion with the risk of lower limb ischemia and amputation.
What is the treatment for aortic aneurysms?
The main reason for treating an aortic aneurysm is to avoid rupture , which has a very high mortality rate. Because the probability of rupture is directly related to the size of the aneurysm, indication limits have been established based on this. The indication for surgery always arises when the probability of complications from surgery is lower than the probability of complications if the patient does not undergo surgery within a year, as long as he has a life expectancy of more than 2 years.
Therefore, when the thoracic aorta exceeds 6 cm in diameter and the abdominal aorta exceeds 5.5 cm in men and 5 cm in women, there is an indication for their treatment. Another indication for surgical treatment is the rapid increase in the diameter of the aorta of the order of 0.5 cm. over a period of six months, regardless of size. In the case of aneurysms with a particularly asymmetrical morphology or pseudoaneurysms that have an increased risk of rupture, the indication for treatment may be set even before they reach the aforementioned sizes.
Symptomatic aneurysms require immediate surgical treatment. An aneurysm of the common iliac arteries greater than 3 centimeters requires surgical treatment, in which case the accompanying abdominal aortic aneurysm is also treated even if there is no indication.
The treatment of aortic aneurysm is performed both endovascularly withstents,and with the classic open method (see treatments). The appropriate method depends on the morphology of the aneurysm, the general condition of the patient and his life expectancy. The vascular surgeon will advise and inform the patient about all the methods with the respective advantages and disadvantages, so that the best possible method with the fewest complications and the best possible long-term results can be selected.