Stent research leads to FDA approval

The U.S. Food and Drug Adminis-tration (FDA) recently approved the use of a drug-coated stent to treat patients with clogged cardiac arteries.

LaSala in the cardiac cathaterization lab
John M. Lasala, M.D., Ph.D., professor of medicine, reviews images of cardiac blood vessels in the catheterization lab. – File photo

These stents — metal mesh tubes used as scaffolding to keep blood vessels open and unclogged — are laced with low doses of the drug sirolimus to help prevent clogging. The University was one of the key participants in the research that led to FDA approval.

These are the first drug-coated stents to receive federal approval.

“Drug-coated stents may be the most important advancement in interventional cardiology this decade,” said John M. Lasala, M.D., Ph.D., professor of medicine and director of cardiac catheterization at the School of Medicine and Barnes-Jewish Hospital. Lasala was the medical center’s principal investigator for studies involving sirolimus-coated stents and led the team in three such trials.

About 11 million Americans suffer from coronary artery disease, an inflammation of the blood vessels that deliver oxygen to the heart. Coronary artery disease can lead to chest pain or heart attack and remains the single leading killer of men and women in this country.

To treat the buildup of plaque that causes coronary artery disease, interventional cardiologists first use a balloon to reopen the blood vessel (a procedure called angioplasty) and then insert an expandable stent, which supports the vessel wall and maintains blood flow. This approach is less invasive and less expensive than the alternative: traditional bypass surgery.

In 2002, there were 1,320 stent procedures performed at Barnes-Jewish Hospital.

Unfortunately, roughly 15 percent to 20 percent of all stented vessels close again, or restenose, after the procedure, and patients must undergo a second catheterization.

By coating the stent with drugs, researchers hope to block the cell growth that produces scar tissue and prevent reclogging. Studies of drug-coated stents in Europe and the United States indicate that these new devices can more than halve the rate of restenosis.

“It is absolutely astounding how much progress we’ve made in the last decade,” Lasala said. “Now, thanks to drug-coated stents, we’re close to the ‘holy grail’ — single-digit restenosis rates. These results provide hope for treating millions of cardiac patients.”

The stents coated in sirolimus (also known as rapamycin or Rapamune) are manufactured by Johnson & Johnson.