Abdominal aortic aneurysms can happen anywhere below the diaphragm. The infrarenal area of the abdomen, just below the kidneys, is one of the most common places to develop an abdominal aneurysm.

The aorta is the largest artery in your body and carries blood from your heart and lungs to everywhere else. Although your aorta is thick and large (running the length of your chest and abdomen), it can still feel the strain of its lifelong workload.

Blood is pushed through the main section of the aorta with great force, and age (alongside other risk factors) can increase your chances of developing stretching, bulging, or tears in your aorta. Bulges that result from this increased pressure over time are called aneurysms.

Above the diaphragm, this condition is called a thoracic aneurysm. Below the diaphragm, it’s called an abdominal aortic aneurysm.

These bulges can develop throughout the abdomen but are most common in the area around the stomach, specifically in the spot just below the kidneys. This article will explore what’s unique about an infrarenal abdominal aortic aneurysm, why they develop, and what symptoms you might experience if you have one.

An infrarenal abdominal aortic aneurysm is a type of abdominal aortic aneurysm.

In fact, aneurysms in this area (just below the kidneys) are the most common type and location for abdominal aortic aneurysms.

Infrarenal abdominal aortic aneurysms make up about 60% of all abdominal aortic aneurysms. Abdominal aneurysms are also more common than those that develop in the thoracic area (above your diaphragm).

Unlike thoracic aortic aneurysms, which can develop with symptoms like chest pain and shortness of breath, abdominal aortic aneurysms can develop silently, with no symptoms at all. When symptoms do appear, they can include things like:

Abdominal aortic aneurysms range in size. An abdominal aortic aneurysm that is between 3 and 4 centimeters in diameter is considered small. Anything larger than 5 centimeters in diameter is considered a larger aneurysm that may require treatment.

No matter where they’re located, aneurysms can burst if they become too large. An aortic rupture or dissection develops when the bulge tears the artery wall. These are medical emergencies that could lead to massive blood loss and death.

Aortic aneurysms have a few shared risk factors, particularly things that increase the pressure of the blood that’s pumped through your arteries.

High blood pressure, high cholesterol, cardiovascular diseases, some connective tissue diseases, and injuries or infections can all lead to the formation of an aneurysm.

For abdominal aneurysms in particular, hardening of the arteries (atherosclerosis) is a common cause, and this issue is most common in white men older than 65 years.

If your infrarenal abdominal aortic aneurysm measures on the smaller end of the spectrum, imaging is usually done every 3 years after the initial diagnosis to monitor the aneurysm for growth or other changes.

Medium-sized aneurysms measuring between 4 and 5 centimeters require more frequent monitoring, so aneurysms of this size will be scanned and measured each year.

Aneurysms that are larger than 5 centimeters in diameter require imaging every 6 months to check for growth and other complications. You may also be prescribed medications to help control issues that are contributing to your risk, aneurysm risk, such as high blood pressure or high cholesterol.

Surgical removal is recommended for larger aneurysms, like those measuring 5.5 centimeters or larger. When surgery is warranted, it can come in two forms:

  • Open surgical repair: This requires an incision in the area behind your abdomen, in the retroperitoneal area, or along the center of your abdomen. Your surgeon will have to access the aorta and iliac arteries. These arteries will be clamped, and a graft will be placed to repair the weakened area of the vessel.
  • Endovascular aortic aneurysm repair (EVAR): This strategy uses a catheter to re-route blood flow during the operation so that the aorta doesn’t have to be clamped during placement of the graft/stent. Leaving aortic blood flow intact during the procedure can help reduce the risk of complications like blood clots.

Infections, bleeding, and the formation of blood clots are all risks you can expect with an aortic aneurysm repair. However, not treating a large aneurysm could be fatal if you experience an aortic rupture or dissection.

Most aneurysm repairs result in long-term success, but some people do develop complications later on, such as:

  • movement of the graft/stent
  • leaking around the repair
  • infection

Open surgical repair results in less repeated repairs for people with abdominal aortic aneurysms, but the EVAR method results in faster healing and fewer post-operative complications.

An aneurysm is a weak spot that forms in an artery, putting you at risk of a full rupture or tear. Infrarenal abdominal aortic aneurysms develop in the abdominal area below the kidneys.

Smaller aneurysms can be monitored, but if they become larger and put you at risk of a massive tear and bleeding, surgery might be recommended to repair the aneurysm before it turns into an emergency.