July 6 (HealthDay News) -- In recent decades, long-term survival of patients who have surgery to repair intact abdominal aortic aneurysms has improved, a new study from Sweden finds.

The researchers also found that short-term survival has improved and long-term survival has remained stable for patients who have surgery to repair ruptured abdominal aortic aneurysms.

An abdominal aortic aneurysm is a bulge in the aorta (the main artery leading away from the heart) that occurs in the abdomen, the American Heart Association explained in a news release about the study. If the bulge bursts, the patient suffers potentially deadly internal bleeding. Intact aneurysms can be monitored or surgically repaired, while burst aneurysms require emergency surgery.

In the new study, published in the July 6 issue of the journal Circulation, the Uppsala University Hospital researchers analyzed patient outcomes of 8,663 surgical repairs of intact aneurysms and 4,171 operations to repair ruptured aneurysms conducted between 1987 and 2005.

The five-year survival rate for patients who had surgery to repair intact aneurysms was 90.3 percent, with patients surviving an average of almost nine years after surgery, the researchers found. The short-term survival rate for patients who had emergency repair of a burst aneurysm was 87 percent, with patients living an average of 5.4 years after surgery.

Age and gender affected survival among patients who had surgery to repair intact aneurysms, the study authors noted. Survival was 10.2 percent higher among those in their 80s than those aged 79 and younger, and was 4.6 percent higher for men than for women.

The researchers said advances in postoperative care have helped improve short- and long-term outcomes in patients with intact and ruptured abdominal aneurysms.

SOURCE: American Heart Association, news release, July 6, 2009