Opening of Kidney Arteries Brings Dangers

ByABC News
March 24, 2008, 12:26 AM

Mar. 23 -- FRIDAY, June 29 (HealthDay News) -- Angioplasty and stenting can open blocked kidney arteries, but the procedure also throws off an immense amount of debris that can hurt kidney function, a new study shows.

It has been known that this procedure -- done primarily to relieve high blood pressure -- is messy, but "this is the first paper in humans to really demonstrate how much stuff there is and especially how much microscopic material there is," said Dr. Matthew Edwards, an assistant professor of surgery at Wake Forest University Baptist Medical Center and lead author of a report in the June issue of the Journal for Vascular Surgery.

Angioplasty and stenting for blocked kidney arteries involves the insertion of a balloon to open the artery, followed by the implantation of a tube to keep it open. The procedure doesn't get as much attention as a similar surgery done for heart vessels, but an estimated 40,000 to 80,000 Americans receive this intervention each year, Edwards said. The operation's primary purpose is to lower blood pressure caused by a blockage, and its ultimate goal is to prevent kidney failure, he said.

The new report described 28 angioplasty cases in which the physicians took blood samples after a stent was implanted.

Laboratory analysis revealed an average of 2,000 debris particles in the blood samples -- some pieces being big enough to block smaller vessels in the kidney.

The number of particles found in specific patients was directly related to their subsequent kidney function, the researchers found: more debris, worse kidney function.

That can bode ill for patient's longer term health, Edwards said, since "poor kidney function after kidney artery stenting has been previously demonstrated by our group to be associated with increased risk of heart attack, stroke or death in the future."

Post-angioplasty debris was also found to float freely in arteries, even though the surgeons used a protective device designed to trap it for removal. The Wake Forest surgeons used one of several protective devices now being tested. None have yet been approved by the U.S. Food and Drug Administration.