An aortic aneurysm is a permanent local dilatation of the aorta. It most commonly results from a process called atherosclerosis, where plaque builds up on the interior wall of the artery. This reduces the flexibility of the aortic wall, gradually damaging it and creating weak spots. An aneurysm starts to form when those weak spots cannot handle blood pressure, which then leads to that wall expanding. If not treated, aneurysms may burst, causing imminent death.
Genetic causes of aortic aneurysms
Children may be born with an aortic aneurysm in extremely rare cases. This is called a congenital aortic aneurysm, and only a small number of cases were identified to date.
Marfan syndrome is a characteristic example of a connective tissue disease. Patients suffering from it lack a certain protein which gives the aorta (among other organs) its form and strength. Patients usually have a characteristic tall and thin physical appearance, but due to the fact that the symptoms tend not to manifest until it’s too late.
Ehlers-Danlos syndromes (EDS) are a group of several (10 forms have been discovered so far) genetic conditions, where defective collagen fibers are produced. Collagen makes the tissue firm and resistant to stretching, and in EDS, its lack may manifest as extreme flexibility.
Patients can easily touch the tip of their nose with their tongue and bend their fingers backwards. However, affected tissues tend to be more fragile. Because of that, wounds heal more slowly, and the skin is elastic but easily cracks. However, the most dangerous manifestation of EDS is a lack of resistance in the blood vessels. EDS patients easily bleed, and skin bruises form very fast. The aorta may also be affected, which ultimately ends in aneurysm formation.
Loeys-Dietz syndrome (LDS) is often confused with the previous two diseases, because they share some of the same features (bruising, heart defects...). However, the main feature of LDS is the presence of an aneurysm, which can form both in the aorta and other arteries as well.
Several other, albeit less common conditions caused by gene mutations that can also elevate the risk of cardiovascular diseases include Turner syndrome, Noonan syndrome, and Alagille syndrome.
Birth defects can also lead to an aortic aneurysm formation
Other than these genetic diseases, aneurysms may be caused by problems present at birth, primarily ones involving the structure of the heart and the blood vessels.
Bicuspid aortic valve is the most common congenital heart disease. The normal aortic valve has three leaflets, whereas here there are only two — one small, and one bigger, made out of two merged leaflets. Normal blood flow is compromised, which affects both the valve and the wall of the ascending aorta, causing damage which may result in complications such as aortic dissection or aortic aneurysms.
Coarctation of aorta is a birth defect that involves the narrowing of the aortic lumen in a specific place. It also compromises blood flow, mainly by elevating the blood pressure, which further stresses both the heart and the aorta, which, if untreated, may result in an aortic aneurysm.
Symptoms and diagnosis
Often, there are no signs that children may have an existing aortic aneurysm. Aneurysms generally show little to no symptoms, until it’s (too) late – they either get too big, or they burst.
When diagnosing genetic conditions, special tests are utilized to confirm the disease, because some of these conditions show greater risk when it comes to aortic complications. Family history is also a smart idea, because a large number of these conditions are hereditary.
Treatment: How are aortic aneurysms in children managed?
Some patients do not require no management at all, while others can treat their symptoms using only medication. However, surgical interventions are required if the condition is complicated. Open surgical repair is the most common method in this population, although an endovascular aortic repair (EVAR) procedure, usually performed on adults, may also be suitable when talking about the young adult population.
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