Aortic Aneurysm and Dissection
Aortic Aneurysm and Dissection
The aorta is the largest artery in the human body. It begins at the left ventricle and ends in the abdominal cavity. Here it divides into two major branches supplying the lower limbs. It is the main artery from which arteries supplying vital organs such as the brain, heart and kidneys, branch off. From the left ventricle, the aorta is known as the ascending aorta, continuing as the aortic arch, followed by the descending aorta. Furthermore, its parts are named according to where it is passing through. The thoracic and abdominal aortas are distinguished. Aneurysms form mainly in the abdominal aorta, whereas aortic dissection occurs in the thoracic aorta, more specifically the ascending aorta.
An aneurysm is a bulging of the vascular wall. A hallow pocket is created where blood flows. Aneurysms form in weakened areas of vascular walls. Vascular inflammation can be the causes, as it weakens the walls, as well as atherosclerosis and high blood pressure.
Symptoms and Consequences of an Aneurysm
The problem with aneurysms is that until the aneurysm bursts, the condition is typically asymptomatic. Large aneurysms can be palpated in the form of a pulsing area during abdominal examinations. It can put pressure on surrounding organs and cause back or abdominal pain. The presence of aneurysms should always be monitored. In the event that the aneurysm reaches a certain size, typically 5 cm (2 inches), surgery is required. In the thoracic aorta, aneurysms are rare, they usually form in the abdominal area. The danger is that the aneurysm may burst and blood will spill into the surrounding area. Given the size of the aorta and the amount of blood that flows through it, as well as the size of the abdominal cavity, there is a risk of extensive internal bleeding and circulatory collapse. The patient then experiences a very serious condition: shock.
Diagnosing an Aortic Aneurysm
An aortic aneurysm is not easy to diagnose as its size can vary and it usually does not cause any symptoms. In the case of a larger aneurysm, a pulsating area in the middle of the abdomen can be palpated during a physical examination. This finding can be confirmed via a stethoscope, where whirling sounds can be heard. A reliable method for confirming a diagnosis is the use of a CT or ultrasound of the abdomen. A CT or CAT scan is a test that uses x-rays to create a 3D image. Its disadvantage is that it emits a high dose of radiation that the body subsequently absorbs. The ultrasound is a completely safe method as it uses sound penetration and its various levels of absorption in different tissues.
Treating an Aortic Aneurysm
Treatment of aortic aneurysms is based on remediating factors that took part in the development of this disease. Medications from various groups are administered. High blood pressure needs to be lowered, as well as cholesterol levels in the blood. The only way to fix the aneurysm is with surgery. Often the first approach is the insertion of a stent, a metal reinforcement, into the aorta to support its walls. Other methods to support the aortic walls in the bulging area exist, but these are complicated and performed solely by a specialist in vascular surgery.
Aortic dissection is a tear in the vascular wall. Arterial walls consist of 3 layers. If the first, internal, layer is damaged, blood enters between the second and third layer, causing dissection. Unlike an aneurysm, aortic dissections usually form in the thoracic aorta. The causes include high blood pressure, diseases of the vascular tissue, and rarely, atherosclerosis.
Symptoms and Consequences of Aortic Dissection
Aortic dissection is a tear in the wall of the ascending aorta. Blood accumulates in the tear and forms a pocket similar to an aneurysm. This pocket can restrict blood flow in the blood vessels, even blocking it completely. The tear can progress further and affect connecting arteries. These can also narrow or close up completely. Aortic dissection is manifested by sudden severe pain behind the sternum, though this condition can spontaneously disappear. Due to the fact the aortic aneurysms commonly occur in the ascending aorta where coronary arteries connect, it can cause a heart attack or affect the aortic valves. Cerebral arteries can also be affected, which is manifested by a stroke, or paralyses of certain parts of the body. The kidneys can also be affected, decreasing urine output. Shock will develop in the event of major blood loss.
Diagnosing Aortic Dissection
Diagnosis of aortic dissection lies primarily in a detailed medical history and the exclusion of acute myocardial infarction with the help of an EKG. A chest x-ray can also be performed, as well as an ECHO, i.e. an ultrasound of the heart. The fundamental method that reveals the vast majority of aortic dissection s is the transesophageal echocardiogram. This is an ultrasonic examination of the heart, where a probe is inserted through the mouth into the esophagus and stomach, and allows more precise imaging of the structure of the heart and aorta.
Treating Aortic Dissection
Aortic dissection is always considered a life-threatening condition, however, its progression may not always be dramatic. Temporary and permanent stabilization of the condition is possible. This depends largely on the size of the tear. Dissection in the thoracic area always requires surgery. Abdominal dissections, in good conditions and without risk of complications, do not require surgery.