Next Generation of Stents Responds to Problems

SATURDAY, March 24 (HealthDay News) -- A new generation of stents, created largely to address problems associated with the current artery-opening devices, made their debut during the American College of Cardiology meeting in New Orleans Saturday.

These new stents attempt to ward off restenosis, the reclosing of a stented vessel, and thrombosis, the dangerous clotting that has been seen mostly in drug-eluting stents. The innovations ranged from coating stents with different and better drugs to building biodegradable stents that dissolve over time.

In one study, researchers compared the standard paclitaxel-eluting stent with a new drug-eluting stent called Xience V. Dr. Gregg W. Stone, director of Cardiovascular Research and Education at Columbia University Medical Center, and his colleagues randomly assigned 1,002 patients to receive stents with either Xience V or the standard drug-eluting stent.

"This is a second-generation drug-eluting stent," Stone said. "This trial was designed to get approval for this stent in the United States."

Stone's team found that after nine months, patients treated with the newer stent had similar rates of failure in the treated blood vessel, but needed fewer new procedures. There were fewer major cardiac events at nine months among patients treated with the XIENCE V compared with the standard drug-eluting stent (4.6 percent vs. 8.1 percent).

The new stent also decreased blood vessel loss and tended to reduce the re-blocking of the treated arteries compared with the standard drug-eluting stent (4.7 percent vs. 8.9 percent), Stone's group reported.

"This stent is at least as safe and effective and, for several of the important endpoints, is superior to the standard drug-eluting stent," Stone said.

Two other studies presented at the meeting by teams of Dutch researchers were on the cutting edge of stent development.

In the first, Dr. Marcel Beijk, from the University of Amsterdam, and his colleagues treated 152 patients with a stent coated with an antibody that attracted the endothelial cells that line blood vessels, and speeded healing. Before the stents were put in place, the patients had two weeks of statin therapy to increase the number of endothelial cells, Beijk explained.

"This accelerated healing may reduce restenosis, and may prevent stent thrombosis," he added.

Over six months, there was one death, one patient had a heart attack, three patients needed further procedures on the stented artery, and one needed stenting in another artery.

"While this is still an early study, it offers a whole new look at the use of stents and the process of healing damaged tissue throughout the body," Beijk said in a prepared statement. "As we look at new treatment combinations, we believe this is a step in the right direction to offer patients better long-term success rates."