The body’s largest artery is the aorta. The aorta comes directly out of the heart and runs down the back side of the abdomen. If the section of the aorta inside the abdomen gets too large, it’s called an abdominal aortic aneurysm.

An aneurysm is a bulge in an artery caused by a weak spot in the artery wall. Abdominal aortic aneurysms are about four times more common in men than in women. It affects about 2% of men over 50 and 5% of those over 65. When they give way and rupture, they can be fatal.

If your husband has this time bomb in his body, why aren’t the doctors doing something right away? That’s a very reasonable question — with a reasonable answer.

Almost every kind of treatment for a medical condition involves risks. So doctors and patients always have to ask whether the risks of the treatment outweigh the risks of the disease. Most abdominal aortic aneurysms never rupture or cause other problems. But the risk gets higher as the bulge of the aneurysm gets larger.

To decide when treatment is necessary, doctors typically order ultrasound tests to see if the aneurysm is getting bigger. Small aneurysms (less than 4.0 centimeters) are re-checked every 2 – 3 years. Medium-size aneurysms (between of 4.0 and 5.4 centimeters) are checked every 6 to 12 months.

Experts have studied thousands of patients. From this, they’ve determined that the risk of rupture begins to outweigh the risk of treatment when an abdominal aneurysm is wider than 5.5 centimeters (a little more than 2 inches). Or it expands by more than 1 centimeter (a little less than half an inch) in one year.

At 5.2 centimeters, your husband’s aneurysm does not meet the standard criteria for surgery. Of course, each person has to be considered on a case by case basis. Perhaps your husband can ask his doctor if he should have a repeat ultrasound before 6 months.