MAKING a popular fix for aneurysms a little safer
Tuesday, August 14th 2001, 12:00 am
By: News On 6
WASHINGTON (AP) _ Thousands of Americans have a weak spot on the body's largest blood vessel that could burst and kill almost instantly. Their options: grueling abdominal surgery or new patches that doctors thread through a small incision.
Patching has become a popular fix for abdominal aortic aneurysms _ but it's not perfect. Dozens of reports of injuries and deaths have federal regulators examining how to make patching safer.
For now, the top advice for patients is to pick a surgeon who really understands the tricky new therapy _ and to commit to checkups every six months to make sure the patch is holding.
``That doesn't mean everybody's endograft is going to fall apart,'' stresses Dr. Hugh Beebe, director of the Jobst Vascular Center in Toledo, Ohio, who chaired a Food and Drug Administration meeting examining the risk.
Beebe calls patching a success for ``the overwhelming majority'' of patients. It's the only option for many elderly patients who couldn't survive open surgical repair.
But about 10 percent of patch recipients face trouble, Beebe says, and ``we don't predict very well which ones are at special risk.''
The aorta is the largest blood vessel, like a river running from the heart to the groin with tributaries that branch off, carrying blood around the body. An aneurysm is a weak spot in the aorta's wall that bulges like a balloon until the pressure of pounding blood bursts it.
Doctors estimate 1.5 million mostly older Americans have abdominal aortic aneurysms, called ``AAAs.'' Because AAAs often cause no symptoms until the day they break, only about 200,000 patients know they have one. Some 15,000 die each year.
Doctors and patients were thrilled when the FDA in 1999 approved the first alternative to risky open-abdominal surgical repair. The patches _ Guidant Corp.'s Ancure and Medtronic's AneuRx _ are slipped through a small incision in a groin artery and threaded up to the aorta to form a sleeve-like new path for blood. Clinical trials showed the patches saved lives while cutting in half surgical side effects and hospital stays.
Thousands have since been treated, largely successfully. But the FDA has reports of 530 injuries and 28 deaths among Ancure users, and 95 injuries and 13 deaths among AneuRx users.
With Guidant's Ancure, the implantation system _ tubes and other gadgets used to position the patch, almost like building a ship in a bottle _ sometimes got stuck. Guidant voluntarily stopped Ancure sales last spring while redesigning it, and now is testing the new-generation Ancure in a 2,000-patient study that Beebe says shows improvement.
Other problems: Sometimes doctors implanted patients whose aneurysms were too big for a patch, or whose arteries had too many kinks to safely thread the device in place. Sometimes a patched aneurysm changes shape so that the sleeve leaks. Patches can move out of place.
Leaky or migrating patches can be corrected, but in some cases ``people didn't understand the importance of it'' and refused additional treatment, say Dr. Christopher Zarins of Stanford University, speaking for Medtronic.
The FDA is working with both companies to improve the devices. Meanwhile, what should a patient consider in choosing a patch over surgery?
_Patches are easy options for older, sicker patients who might not survive open surgery. But for a younger, healthier patient, Beebe advises that open surgery offers a 97 percent chance of a one-time cure. If you get a patch, you'll need a checkup every six months possibly for life, and have a 10 percent chance of needing a patch repair or even open surgery later, he says.
_All patients get CT scans of their aneurysm, but ask that yours be checked using 3-D computer software, Beebe advises. That's the best way to ensure there are no winding arteries where the patch can get stuck or that the aneurysm's not too big to patch.
_Don't be shy about asking how often surgeons have inserted the patch. Doctors learn how to implant the devices and how to pick the right patients at brief manufacturer-run training seminars, so experience is important. The FDA recently wrote thousands of doctors urging they carefully follow patch-implantation instructions and consider turning away patients who probably won't return for checkups.