Radioactive Seeds

[NFRGTBLIS@aol.com]

  Radsafers,

I wondered if anyone had seen this information.  Just an intriguing bit for 
you to peruse.

Melissa J. Engelhard
nfrgtblis@aol.com

Radioactive Seeds May Keep Arteries Open  
February 1, 2000 

NEW YORK (Reuters Health) — Temporarily placing tiny radioactive pellets in a 
heart artery that has just been unclogged during an angioplasty procedure can 
safely prevent reblockage of the vessel over the next 3 years, the results of 
a new study show.

During angioplasty, a balloon-tipped catheter is threaded into a blocked 
artery and inflated, flattening fatty plaques against the artery wall and 
allowing blood to flow more freely through the vessel. Since the artery often 
becomes clogged again, surgeons sometimes implant a metal coil called a stent 
to keep the artery open. But reblockage may still occur when scar tissue 
builds up on the stent.

A technique that involves temporarily threading a ribbon containing 
radioactive pellets into an artery has been successful in keeping arteries 
open in the months after angioplasty, but the long-term effectiveness and 
safety of the procedure has been unknown.

In the current study, a team of researchers led by Dr. Paul S. Teirstein, of 
the Scripps Clinic in La Jolla, California, followed 55 people who had a 
heart artery reclog after angioplasty. Some of the participants already had 
stents, while some received the stents during the study. Twenty-six people 
were picked at random to undergo the radiation treatment.

Three years later, the radiation group fared significantly better than the 
group that did not receive the experimental treatment, Teirstein's team 
reports in the February 1st issue of Circulation: Journal of the American 
Heart Association. Arteries had reclogged in only about 15% of patients who 
underwent radiation, compared with about 48% of those who had not. Also, the 
combined rate of heart attacks, deaths and reblockages was around 23% in 
those who underwent radiation, compared with about 55% of those who did not.

The researchers did not detect any harmful side effects caused by the 
radiation.

In an editorial that accompanies the study, Drs. David O. Williams and Barry 
L. Sharaf, of Brown University School of Medicine in Providence, Rhode 
Island, point out that several questions remain about using radiation to keep 
arteries from becoming blocked again.

For example, Williams and Sharaf note that it is important to determine if 
the effect of radiation varies depending on whether or not a person has 
already received a stent. In addition, they suggest that longer follow-up is 
needed since it may take 5 to 15 years to detect some effects of radiation.

SOURCE: Circulation: Journal of the American Heart Association 
2000;101:350-351, 360-365.


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expressly prohibited without the prior written consent of Reuters. Reuters 
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