Hello everyone, I hope you are enjoying your weekend, although so many are still at work since it is a Friday morning anyways, the weekend has begun already. I have been discussing Aneurysms in my past posts a started by looking at Abdominal Aortic Aneurysms, and I also discussed Aortic Dissection. Today, I will be looking at Thoracic Aortic Aneurysms, as we continue on the Aortic Aneurysm and dissection series.
As mentioned in my post on the abdominal aortic aneurysm, I explained that an aneurysm is a localized dilation that can be permanent but in this post, it is the dilation of the large artery which is the aorta. In my post on Aortic Dissection, I mentioned that the aorta begins in the left ventricle and extends downwards through the thorax and to the abdomen. A Thoracic aorta aneurysm will be a bulge in the aorta at the thorax region, it gives the ballooning of the aorta of the thorax. It is important to know that an aneurysm can occur in any vessel in the body, be it arteries or veins but they are common in the artery and could affect the iliac artery, but in this case, we are looking at the aorta. An aneurysm can bulge up to one and a half times its original diameter. The thoracic aorta aneurysm can be divided into true and false types of aneurysms. With a true aneurysm, the wall of the aorta completely dilates at all sides involving the Tunica intima, media, and adventitia layer dilates as well. This aneurysm can be fusiform when the ballooning is symmetrical, and a true aneurysm can also be saccular having one side of the wall dilate as a result of exposure to higher blood pressure and it is also known as a berry aneurysm, and also aneurysms can be false or pseudo can be as a result of a puncture in the vessel as a result of a trauma causing the leaking of blood through a vessel where the blood begin to cause the bulging but not a bulging of the vessel.
Aneurysm which causes the walls of the aorta to weaken can also cause it to rupture causing blood to spill from the aorta to the tissue in its surrounding thereby reducing the amount of blood being distributed to the body which will lead to tissues in the body getting deprived of oxygen. Aneurysm can lead to thrombosis where there is clotting in the vessel which could later flow with the blood in the case of embolysis and cause major problems in the heart blocking the passage of blood through the vessel. Aneurysms will lead to the compression of the surrounding organs or structure, such as the vena cava which is close to the thoracic aorta becoming compressed. Arteriosclerosis is one major reason for an aneurysm as the wall of the aorta starts to become weak as the condition is a degenerative condition. When there is pressure from the fluid, the walls can also start to weaken and dilate. Not to forget that previous aortic dissection can lead to an aneurysm. Also, connective tissue disorders such as Marfan syndrome can also lead to an aneurysm.
There are a few risk factors that can cause a patient to develop a thoracic aorta aneurysm and these risk factors include, Arteriosclerosis, smoking, hypertension, Chronic Obstructive Pulmonary Disease (COPD), being male, older than 65 years old is another risk factor as older people tend to have weaker vessels as a result of calcification, and the degeneration of the collagen and elastin in the vessel, and genetics is another risk factor. About 75% of people who have thoracic aorta aneurysms do not know they have an aneurysm since most are asymptomatic, and most are found during cases of regular checkups. Patients with symptoms can occur as a result of compressing other structures, such as compressing the laryngeal nerve which controls the vocal chord, also compression of the vena cava would lead to difficulty in the venous return of blood. It can also compress the trachea or the esophagus leading to obstruction of the airway which can also be accompanied by pain in the area of the compression. When a Thoracic aorta Aneurysm ruptures, the major symptom it is accompanied by is hypotension as blood is lost to the surrounding environment. The brain doesn't receive much blood and so the patient faints regularly, patients could also cough out blood in a condition known as hemoptysis if the blood flows to the esophagus or the vomiting of blood known as hematemesis. Identifying an aneurysm is done via imaging using chest x-ray, Computerized tomography CT scan, and MRI. Surgery is the best treatment for aneurysms that are above 5.5cm in diameter or grows above 1cm within a month. The surgeries can be Open surgery where a graft is performed, Endovascular stenting can also be done.