Late blood clots tarnish drug-coated stents

Uncommon complication raises questions about who really needs a drug-coated stent and how long to continue drug therapy after getting one.

Medicine is both science and art. It's also a balancing act, teetering between the benefits of therapies for treating and preventing illness and their hazards. When it comes to new drugs, devices, and operations, healing powers are usually seen first, with harms trickling in over time. That's been the case for drug-coated stents. They were hailed as a huge innovation when introduced in 2003 and almost universally adopted for holding open cleared coronary arteries. Now, with more than four million drug-coated stents implanted in the U.S. alone, an uncommon but hazardous side effect known as late stent thrombosis is giving some cardiologists pause about using them.