FDA says some heart stents raise clot risk

WASHINGTON – Patients implanted with drug-coated stents to hold open their choked arteries face a small but significant risk of blood clots, health officials said Tuesday. A new study recommended they take clot-busting medications indefinitely.

Growing concern about the long-term safety of drug-coated stents comes to a head this week when the Food and Drug Administration convenes a two-day meeting to discuss clotting risks associated with the devices.

In documents released Tuesday, the FDA said it is unknown whether there is an increased risk of death or heart attack in patients fitted with the so-called drug-eluting stents. However, those patients do face an increased risk of blood clots a year or more after surgery compared with people fitted with bare-metal stents, the agency said in citing recent studies.

About 6 million people worldwide have one or more drug-eluting stents in their bodies.

The FDA is seeking advice on a wide range of questions on the stents, including whether to update the labels with new warnings, identify patients for whom they aren’t appropriate and perhaps change federal recommendations on how long people should take blood thinners such as Plavix and aspirin following stent surgery.

The agency also wants advice on what research is needed, both on the drug-coated stents already on the market and others it has yet to consider approving.

The miniature lattice-shaped tubes are coated with drugs that slowly dissolve – or elute – into the bloodstream to prevent regrowth of tissue that can clog arteries anew. Boston Scientific Corp. and Johnson & Johnson are the only companies approved to sell the drug-coated versions.

Labels on those stents recommend patients take baby aspirin and Plavix for either three or six months, depending on the manufacturer, following surgery. Many patients remain on the drugs longer.