MINNEAPOLIS - Patients given drug-coated stents to prop open clogged heart arteries were less likely to die or need repeat procedures than those with older, bare-metal devices, according to a study that may help revive sales of the newer models.
Researchers analyzed the records of more than 7,000 people treated in Ontario after European investigators last year said the drug-coated devices could trigger blood clots and boost death rates up to 30 percent. The results refute those findings, researchers said in the New England Journal of Medicine.
Sales of Natick-based Boston Scientific Corp.'s Taxus and Johnson & Johnson's Cypher stent both plunged more than 30 percent in the second quarter as some doctors elected to use drug therapy to treat blocked arteries and others turned to bare metal devices. Several recent studies failed to find similar risks, but the Ontario review is the largest positive study of drug-coated stents, which generated $5.3 billion in 2006.
"A year ago, people were saying these devices might be killing people," said Jack V. Tu, the lead researcher from the University of Toronto. "With the publication of our data, I think people may be reassured that they are not."
Stents are wire-mesh tubes that help prop open arteries that have been cleared of fatty clogs. While the results are important, they need to be confirmed in larger clinical trials before anyone can conclude that the drug-coated stents save lives, said Tu.
The Ontario Ministry of Health, the Canadian Institutes of Health, and other medical groups funded the research, which was conducted without industry involvement.
The highest-risk patients were most likely to benefit from newer devices, which can cost $3,000, or 10 times the price of bare-metal stents. Patients with diabetes, tiny vessels, and long blockages reaped most of the benefit, the researchers said.
In the study, 7.4 percent of patients given drug-coated stents needed another procedure within two years to restore full blood flow, compared with 10.7 percent of those who received a bare-metal stent.
After three years, 5.5 percent of drug-coated stent patients had died, compared to 7.8 percent given older devices.