"There is no disease more conducive to clinical humility than aneurysm of the aorta."
— Sir William Osler
(1849-1919) Canadian physician and "Father of Modern Medicine"
One of the most catastrophic events that a medical practitioner can encounter in an emergency setting is that of a ruptured AAA, or abdominal aortic aneurysm. Unfortunately, for most patients who suffer a ruptured AAA, the result is death.
The aorta is the largest blood vessel in the body. It originates directly from the heart and descends down through the chest or thorax into the abdomen, and finally divides in two to supply both legs. Along the way it gives off branches or arteries that supply the various vital organs and body parts from head to toe. As you can see, it is the "vital highway" of nourishment and oxygenation for the body.
An aneurysm is an abnormal, balloon-like dilatation of the blood vessel wall that can occur anywhere within the vascular system. This dilation stretches the wall, making it vulnerable to rupture. It typically arises in areas where the walls of the arteries are weaker, and where there are higher pressures within the arterial system. An aortic aneurysm may arise from any point along the course of the aorta; however, due to the anatomical design of the aorta, nearly 80 percent of aneurysms in the aorta are in the abdominal region, while the remainder occur within the thoracic or chest area.
The risk of rupture is based on the size of the aneurysm. The greater the size, the greater the risk of rupture. A small abdominal aneurysm of less than 4.0 cm in diameter has almost no risk of rupture, for example, while an abdominal aneurysm that is 8.0 cm or greater in diameter has between a 30 and 50 percent risk of rupture. Most surgical intervention begins much earlier and is based on initial size of aneurysm, rate of increase in size compared to previous diagnostic tests, location of aneurysm, sex of patient, as well as other underlying conditions that the patient may have. Although AAA are less likely to occur in women compared to men, if a AAA does occur in a woman it does not have to have as large a diameter for it to rupture.
While most will not have any symptoms, some may develop symptoms such as a deep abdominal pressure or pain, back pain, abdominal pulsations, lightheadedness due to drop in blood pressure (from bleeding into the abdomen), or cool, clammy skin. It is estimated that nearly 2 million Americans have an AAA, but according to a recent study presented at an American Heart Association forum, only 2 out of 43 at risk people get the proper screening.
Based on extensive research, there are several risk factors that increase the risk of developing an AAA. Some of these risk factors include: age greater than 65 years, white males, current or prior smoking history of at least 100 cigarettes (5 packs) during their lifetime, family history of aneurysms, other conditions such as hypertension, peripheral vascular disease, cardiac disease, obesity, high cholesterol, diabetes, etc.
Here are some steps that we can take to prevent this medical and surgical emergency. Stop smoking, improve blood pressure – Optimal control would be a blood pressure less than 120/80 mm Hg, or as low as tolerated is better.
Maintain a healthy weight, healthy diet and exercise regimen, and early screening if there is a family history of aneurysms.
For now, there are no uniform guidelines to suggest screening women and those younger than 65 years. However, certain individuals may have specific risk factors that could pose a risk and may warrant earlier screening. Your specific screening requirements should be discussed with your healthcare provider, in addition to preventive measures, diagnostic testing and specific interventions.
This article was written for general information purposes and is not meant to substitute the personalized care of your doctor. Please check with your doctor, to see what therapies and/or preventative measures are available and if they are right for you and your family, prior to making any significant changes to your medical regimen and /or lifestyle.
For more information, please visit the following websites:
US National Library of Medicine and the National Institutes of Health — www.nlm.nih.gov
National Heart Lung and Blood Institute — www.nhlbi.nih.gov
United States Preventive Task Force — www.ahrq.gov
American Heart Association — www.americanheart.org