Abdominal aortic aneurysms (AAAs) are a progressive malady that can cause ruptures and sudden death if not detected. An abdominal aortic aneurysm (AAA) is a large, bulging area in the wall of the abdomen's main artery, the aorta. Aneurysms develop when parts of the artery wall become abnormally weakened and have open spaces. These weakened areas allow blood to push through with increased force and cause widened arteries.
One in 50 people over age 60 will develop an abdominal aortic aneurysm each year. The risk increases with age - about one out of four people over age 80 will develop it at some time in their life. The symptoms include persistent back pain, high blood pressure, or heart failure and are usually not specific enough for diagnosis on their own.
Aneurysms most often occur when the wall of the artery (the media) becomes stretched, weak, and thin. The exact cause of abdominal aortic aneurysm is unknown. However, there are several risk factors that may increase one's risk of developing this condition:
The most common cause of an abdominal aortic aneurysm is aging. An estimated 10โ15% of people over the age of 80 suffer from an abdominal aortic aneurysm. Aneurysms typically develop in females more than males at about two times the rate of males.
More than half of the cases happen in men between 65 years old and 80 years old, but they still occur with some frequency in women. Ruptured AAA is the third leading cause of death from atherosclerotic disease, second only to stroke and heart attack.
Many AAAs never rupture, even after decades of existence. This is because many people with an AAA have no symptoms at all until it's too late to intervene therapeutically.
There are two kinds of AAAs: the most common one is called "saccular" (SAA) and the other one is called "fusiform" or "femoral". Both types of AAAs have a similar natural history. Ruptures are more common in the fusiform kind, whereas the saccular kind is more likely to cause death due to AAA-related clots.
The cause of SAA is unknown, but some risk factors have been identified, including age, male sex (female carriers also), smoking (which may act through acceleration in calcification), family history and genetic variations in chromosome 9p21. SAA occurs more frequently in African Americans.
SAA can appear suddenly or develop slowly over years. The average age at presentation is 65 years, but it can be as low as 50 and as high as 80, especially for the femoral kind. Usually more than 20% of cases are discovered too late to save the life of the patient.
The most common symptoms include pain, a feeling of indigestion or backache, chest discomfort and shortness of breath. In many cases the pain starts by a neurological attack: abdominal distension ("tummy pains'') sometimes associated with dyspepsia or nausea, giddiness and sweating. As the rupture progresses there may be bleeding from the nose or ears.
A ruptured AAA can be fatal within a few hours, either because it causes sudden cardiac death or rapid blood loss. Between 5 and 10% of patients die before being able to reach a hospital, at home or in the car. In some other cases, the rupture is discovered too late for surgery to save the patient's life: this situation is called "incarcerated AAA".
Patients with AAAs usually have diagnosed anemia or arterial hypertension. There are other possible symptoms associated with AAA rupture: syncope, chest pain due to myocardial infarction and pericarditis. An incarcerated AAA is likely to cause abdominal pain and distension.ย
