Study Finds Radiation Curbs Artery Re-Cloggi

["Sandy Perle" <sandyfl@earthlink.net>]

Add this tidbit to the "positive" benefits of radiation in the medical 
world:

Tuesday November 10 7:16 AM ET 

DALLAS (Reuters) - Radiation seems to be a surprisingly simple 
way to prevent the re-clogging of arteries after damaged human 
blood vessels are reinforced with special tubes, the American Heart 
Association was told Monday.  

Dr. Ron Waksman, a researcher at the Washington Hospital 
Center in Washington, D.C., said his studies found that radiation 
helps prop up these reinforced blood vessels, cutting by more than 
half the incidence of re-clogging.  

``We saw dramatic results... which we feel is a breakthrough,'' 
Waksman reported to the heart association at its annual meeting 
in Dallas.  

He said one-fourth of the perhaps 500,000 stents -- mesh-like 
scaffolding tubes -- placed in coronary arteries of U.S. patients
each year quickly become clogged by scar tissue.

He explained that the action re-blocks blood flow to the heart, 
robbing patients of strength and endangering their lives.

Stents are often placed in damaged arteries during a procedure 
called angioplasty, during which surgeons stretch open blocked 
blood vessels by threading through them an inflated balloon 
attached to a catheter.  

``About 25 percent of stents will re-clog and half these patients are 
'frequent fliers,''' Waksman said, referring to the group whose stents 
begin clogging within months and continue to re-clog following 
repeat angioplasties to re-open them.  

``I've had patients whose stents have clogged so often they've had 
to receive seven angioplasties in two years,'' he said. ``It's a
chronic disease that destroys their quality of life and previously 
they've had no treatment that's been able to help them.''

Waksman said he conducted a study of 130 patients with clogged 
stents. He said half received radiation following angioplasties to 
reopen arteries, while the other half received a placebo.  

The researcher said he found that six months later that 61 percent 
fewer patients on radiation were experiencing re-clogging than 
those on a placebo.  

What's more, he said, patients undergoing the radiation therapy 
had a 63 percent reduced incidence of death, heart attack or other 
adverse events.  

``I'm not aware of any trial to reduce restinosis (re- clogging of 
arteries) that comes even close to this trial,'' Waksman said.

He said that although anti-platelet and ``clot-buster'' drugs save 
lives of heart attack patients, the medicines have little, if no
ability to prevent re-clogging of arteries.

He said stents scrape the inside of their host arteries, creating a 
wound that the body repairs by recruiting clotting cells that form 
troublesome scar tissue that clogs the artery.  

Radiation apparently works, he explained, by arresting the wound-
healing process and somehow slightly widening the size of the 
artery.  

Waksman said he does not believe that the radiation -- the 
equivalent of two chest X-rays -- will increase the patients' risk of 
cancer.  

``The radiation is pretty much confined to the coronary artery itself, 
which is not very vulnerable to cancer,'' he noted.

Sandy Perle
E-Mail: sandyfl@earthlink.net 
Personal Website: http://www.geocities.com/capecanaveral/1205

"The object of opening the mind, as of opening 
the mouth, is to close it again on something solid"
              - G. K. Chesterton -
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