Those who have a family history ex: parents, siblings or children with thoracic aortic aneurysms may share a genetic abnormality and therefore are more likely to have a thoracic aortic aneurysm themselves. The aortic valve is located at the base of the aorta where it meets the heart. The purpose of the aortic valve is to open when the heart beats to allow blood to be pumped from the heart into the aorta and out to the body and then, when the heart relaxes, to close and prevent blood from leaking backward into the heart.
These leaflets hang down from the walls of the aorta and, when the valve is closed, meet in the middle to form an effective seal. In some cases such bicuspid valves may function relatively well, but in most cases they are either narrowed a condition known as aortic stenosis or they leak a condition known as aortic insufficiency or regurgitation.
It is now recognized that approximately 50 percent of those born with a bicuspid aortic valve also have a dilated ascending thoracic aorta the part of the aorta arising from the heart and going up the front of the chest. If this segment enlarges significantly it is called an ascending thoracic aortic aneurysm. The aorta enlarges due to a weakness in the aortic wall that is due to a process called cystic medial degeneration, similar to a pattern seen in Marfan syndrome, in which the structural elements that give the aortic wall its strength are either abnormally weak or reduced in number.
Therefore, it is essential that anyone who has a bicuspid aortic valve undergo an imaging study, such as a CT scan, MRI scans or echocardiogram ultrasound examination of the heart , to see if his or her ascending thoracic aorta is enlarged.
It is due to an abnormality in the gene responsible for the formation of fibrillin-1, which is a major structural component of the fibers called elastin that give the normal aorta its remarkable strength. A defect in elastin makes the aorta weak, and a weak aorta is prone to stretch over time and become an aneurysm.
Patients with Marfan syndrome are at markedly increased risk for both aortic aneurysm formation and the occurrence of aortic dissection. Most of the time thoracic aortic aneurysm aneurysms aneurysms in the chest do not cause any symptoms when first diagnosed. Most of these aneurysms are instead discovered incidentally when patients undergo a chest x-ray, an echocardiogram ultrasound examination of the heart or a CT scan of the chest that was ordered for some other reason. Unfortunately, in some cases aneurysms may go undetected until they grow large enough that they either rupture or cause a tear that results in a life-threatening condition known as aortic dissection.
The size of the aneurysm as determined on a CT is the most important piece of information in determining the need for treatment. Surgery is recommended when aneurysms grow large enough that they have a significant risk of tearing. The purpose of surgery is to repair or replace the aneurysm to prevent such a life-threatening tear from occurring. The specific size at which we operate differs depending on the location of the aneurysm, how quickly the aneurysm is growing and the age of the patient.
In general we will operate on aneurysms of the ascending aorta when the reach anywhere from 5. In some cases, even when an aneurysm is this large, we may still recommend surgery if it is causing problems for the heart or other organs, or if it is producing pain, shortness of breath or circulation problems.
The surgery to repair aortic aneurysms carries a small but real risk. When aneurysms are relatively small, the risk of an aortic tear or rupture is small, so the risk of surgery outweighs the risk of going without surgery. However, when an aortic aneurysm is larger, as discussed in the prior answer, the risk of surgery is generally lower than the risk of no surgery, so surgery is recommended.
The aorta is replaced with an artificial tube, not unlike replacing a broken piece of pipe with a new one. The woven material is durable and the graft will last for your lifetime. Although people with artificial heart valves do have to take antibiotics for dental work in an effort to prevent their new valves from getting infected, fortunately those with an artificial aorta do not.
The body covers over the aortic graft with a surface coating of cellular material called a neo-intima, and the risk of subsequent infection of the graft is extremely small.
Nevertheless, we do recommend avoiding any unnecessary dental cleanings for the first six months following your surgery, just to minimize any potential risk as the body is first healing. In certain circumstances, and for certain aneurysms that do not involve the ascending aorta, there is a new technique known as stent graft repair. It is the equivalent of a minimally invasive approach for aneurysm repair.
Such stent-graft procedures can only be performed at select medical centers by physicians specifically trained in this field. The major advantage of this method is the avoidance of the large chest incision that open surgery requires. When an aneurysm is not large enough that you need surgery, your doctor will treat you with medications to control your blood pressure and heart rate, in order to reduce the force of your blood against the wall of the aorta.
The size of your aorta will be followed closely with repeated CT scan, MRI scans or echocardiograms ultrasound examination of the heart to monitor for any growth. If the aneurysm grows large enough in size, surgery may then be recommend. You may want to take a fibre supplement every day. If you have not had a bowel movement after a couple of days, ask your doctor about taking a mild laxative. Your doctor will tell you if and when you can restart your medicines.
You will also get instructions about taking any new medicines. If you take aspirin or some other blood thinner, ask your doctor if and when to start taking it again.
Make sure that you understand exactly what your doctor wants you to do. Be safe with medicines. Take pain medicines exactly as directed. If the doctor gave you a prescription medicine for pain, take it as prescribed. If you are not taking a prescription pain medicine, ask your doctor if you can take an over-the-counter medicine. Do not take two or more pain medicines at the same time unless the doctor told you to. Many pain medicines have acetaminophen, which is Tylenol.
Too much acetaminophen Tylenol can be harmful. If you think your pain medicine is making you sick to your stomach: Take your medicine after meals unless your doctor has told you not to. Ask your doctor for a different pain medicine. If your doctor prescribed antibiotics, take them as directed. Do not stop taking them just because you feel better. You need to take the full course of antibiotics. If you have strips of tape on the incision, leave the tape on for a week or until it falls off.
Wash the area daily with warm, soapy water, and pat it dry. Other cleaning products, such as hydrogen peroxide, can make the wound heal more slowly. You may cover the area with a gauze bandage if it weeps or rubs against clothing. Change the bandage every day. Keep the area clean and dry. For example, call if: You passed out lost consciousness. You have severe trouble breathing. You have sudden chest pain and shortness of breath, or you cough up blood.
You have chest pain or pressure. This may occur with: Sweating. Shortness of breath. Nausea or vomiting. Pain that spreads from the chest to the neck, jaw, or one or both shoulders or arms. Dizziness or light-headedness. A fast or uneven pulse. After calling , chew 1 adult-strength aspirin. Wait for an ambulance. Do not try to drive yourself. Call your doctor or nurse call line now or seek immediate medical care if: You have new or increased shortness of breath.
You are short of breath and cough up foamy, pink mucus. You are dizzy or light-headed, or you feel like you may faint. You are sick to your stomach or cannot keep fluids down. You have pain that does not get better after you take pain medicine.
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