Unless their patients remain on Plavix, a 4-U.S.-dollar-a-day anti-clotting drug whose long-term safety has not been proven, doctors are worried these stents may raise the risk of life-threatening blood clots months and even years later.
And thousands of others each day who develop new blockages are being treated by doctors no longer sure of what to do. Many are returning to the old metal stents, and some are fundamentally rethinking when to use stents at all and are considering alternatives like bypass surgery or medications.
Doctors also worry about overreacting to what appears to be a small risk of five or fewer clots in every 1,000 patients.
"The benefit of having a drug-eluting stent is tremendous," said Dr. Elizabeth Nabel, director of the National Heart, Lung and Blood Institute.
Stents are used in angioplasty. Doctors push a tube to a blocked heart artery through a blood vessel in the groin and inflate a balloon to flatten the clog and prop the artery open with a stent.
About 652,000 Americans had angioplasty in 2003 -- more than twice the 268,000 who had bypass operations, which are riskier, costlier and take far longer to heal.
Angioplasty became more popular when the first drug-coated stent came out in 2003, virtually eliminating the procedure's main drawback: scar tissue requiring a repeat effort to reopen the vessel.
A Food and Drug Administration panel will meet on the issue Thursday and Friday. Medical journals are rushing studies into print, and powerful doctor groups are reconsidering treatment guidelines.
source - Xinhua