Q. I am a 72-year-old male in excellent health. I have been diagnosed with a 3.7-centimeter aortic aneurysm. My doctor recommends an ultrasound every six months. Are six-month checks adequate? And when should surgery be considered?
A. I assume this is an abdominal aortic aneurysm (AAA) and that it was detected by a screening exam, not because you had a symptom such as back pain. Indeed, the U.S. Preventive Services Task Force recommends screening all men who have ever smoked and are between 65 and 75. The test is a simple, entirely safe abdominal ultrasound, and it need not be repeated if it’s normal.
But what should you do if your exam is not normal? In your case, the answer is easy. The normal aorta is about 2 centimeters (cm) wide in the abdomen, so your aneurysm is very small, and periodic follow-up exams will suffice. Be sure your blood pressure and cholesterol are excellent, avoid tobacco in all forms, and be alert for back pain that might signal enlargement of your AAA.
Larger aneurysms are more worrisome. Doctors in Minnesota found that aneurysms of less than 4 cm are not at any risk of rupturing, and the annual risk for those between 4 and 4.9 cm is just 1%. But the risk jumps to 11% for AAAs between 5 and 5.9 cm and to 25% for larger aneurysms. Based on this study and others, most doctors recommend repair for aneurysms of 5.5 cm or larger, for those that expand by more than 0.5 cm, and for those that cause pain. And when repair is needed, endovascular stent grafts are increasingly attractive alternatives to conventional open surgery.
Screening tests aim to detect problems early, before they cause symptoms or clinical problems. That’s the good news; the bad news is that screening can also turn up minor abnormalities that cause more worry than illness. Your AAA appears to be in the latter group, and simple follow-up checks can ensure it will stay that way.
— Harvey B. Simon, M.D.
Editor, Harvard Men’s Health Watch