Dr. Kevin Halow, MD MBA RVT FACS
Often when I counsel patients on an Abdominal Aortic Aneurysm (AAA) repair, one of the most common questions that I hear is, “Will fixing the AAA make me feel any better”? Before we answer that question, let’s start by learning a little bit about Abdominal Aortic Aneurysms.
The Aorta (A-or-Ta) is the large blood vessel that begins at the heart and travels through the chest and into the abdomen to carry blood that is pumped from your heart out to the body. Like a tree, the Aorta has branches that take that blood to your brain, vital organs, and extremities. The Abdominal Aorta is that portion of the Aorta that is located within the abdomen. (As an aside, the Thoracic Aorta is that portion of the Aorta that is in the chest—The Thorax.) –Stay with me on this—
An Aneurysm (An-ur-ism) is an enlargement of any artery. In order to be classified as an aneurysm, the artery has to be 50% larger than the normal artery and have thrombus (clot) present within the artery. For example, if the normal artery size is 2 cm in diameter, in order to be classified as an aneurysm, that artery would have to be at least 3 cm in diameter and have some thrombus present in the artery. –Let’s put this all together now—
An Abdominal Aortic Aneurysm is an enlargement of the abdominal portion of the Aorta such that it is at least 50% larger than the normal artery and has some thrombus present in the Aneurysm section. We abbreviate an Abdominal Aortic Aneurysm by simply calling it an AAA.
The problem with an AAA is that as it becomes larger it can actually rupture just like a balloon would rupture if you put too much air in it. The law that governs this risk of rupture is called Laplace’s Law and it has to do with the amount of surface tension on the artery. — For those of you nerds who really need a better explanation, click on this link or copy and paste it into the URL: http://hyperphysics.phy-astr.gsu.edu/hbase/ptens.html — As the radius of the Aneurysm increases so does the surface tension. Eventually the surface tension becomes so large that it disrupts the tissues of the Aorta and the Aneurysm ruptures.
As you would expect, rupturing an Aortic Aneurysm is not particularly compatible with life. Your total blood volume is approximately 5 liters and your heart pumps that entire blood volume through your body every minute. Assuming that half of that blood volume goes through the abdominal aorta every minute, rupturing that vessel means that you can bleed to death rather quickly. The trick, therefore, is to fix the Aneurysm before it ruptures.
Currently, the standard of care requires that we offer AAA repair to any patient whose AAA is greater than 5.5 cm or is greater than 5 cm and has demonstrated interval growth in size on serial exams.(3) The main reason for this number is that it is the point at which the risk of rupture outweighs the risk of surgery. While there have been some who have argued for repair AAAs at a smaller size, the UK Small Aneurysm Trial clearly demonstrated that there is no survival benefit for fixing an AAA at less than 5.0 cm.(4)
In the past fixing an AAA required a major abdominal surgery with a prolonged hospital stay and recovery period. However, current technology has changed the process. We now use an Endovascular Aneurysm Repair. (EVAR) The entire procedure is abbreviated AAA EVAR. (Abdominal Aortic Aneurysm Endovascular Aneurysm Repair.) In this procedure, we insert a specially designed graft into the artery from each femoral artery in the groin region. This repairs the artery from the inside. The procedure takes about an hour with an overnight stay in the hospital. Recovery time is about a week or so.
Click on this link or copy and paste it into the URL for an animation of how we do an AAA EVAR
Let’s recap. An Abdominal Aortic Aneurysm (AAA) is when the artery is more than 50% larger than the normal Abdominal Aorta and has thrombus present. The biggest risk of an AAA is the risk of rupture. That risk increases with the diameter of the AAA. We fix Aneurysms using a procedure called a AAA EVAR.
The only purpose of fixing an AAA is to prevent you from dying of a rupture AAA. Fixing an AAA will not make you feel better, it will not make you look better and it certainly will not improve your golf game. In fact, a AAA has nothing to do with your golf game at all, unless of course you use the extra years that you have gained by having your AAA fixed to practice your golf swing.
- Chaikof EL, Dalman RL, Eskandari MK, Jackson BM, Lee WA, Mansour MA et al. The Society for Vascular Surgery practice guidelines on the care of patients with an abdominal aortic aneurysm. J Vasc Surg. 2018;671:1-75.
- Schermerhorn ML, CronenWett JL. The UK Small Aneurysm Trial, J Vasc Surg. Feb 2001; 33(2):443