Ninety-five percent of patients with ruptured AAAs die, including 50 percent to 70 percent of those who have emergency surgery. Preventive surgery can save patients whose aneurysms happen to be detected earlier, though it is reserved for defects that have grown to a particularly large size. So a drug treatment that could prevent small aneurysms from enlarging could prevent thousands of operations and deaths each year. AAAs arise in the large artery that carries blood from the heart to the abdomen. A weak area in the wall tends to enlarge and eventually to balloon out, like a rupturing inner tube.
Blood then courses into the abdomen, killing within hours or even minutes.
These protein-destroying enzymes are secreted by white cells called macrophages, which fight infection but also can harm host tissues. They also attack elastin, a protein that helps strengthen the wall, enabling it to withstand the force of the heart's pumping. So we see a great need for a preventive treatment other than surgery. Encouraged by their years of laboratory studies, the researchers gave a one-week course of doxycycline to eight patients who were about to undergo preventive surgery for AAAs. The patients took 100 mg of the drug each morning and 100 mg each evening.