When people develop significant blockage in the arteries that feed the heart, doctors often perform percutaneous coronary intervention of PCI. In this procedure, a tiny balloon-tipped catheter is threaded through the artery into the area of narrowing. The balloon is inflated to open the artery. The balloon also expands a tiny mesh cylinder called a stent that will continue to hold the artery open after the balloon is deflated and removed.
Plain metal stents have a tendency to become clogged again after a period of time. That is why cardiologists have embraced stents that are coated with medication to prevent tissue regrowth inside the stent. The drawback of these drug-eluting stents is that they are prone to trigger blood clots that can stop the flow of blood to that part of the heart: in other words, an induced heart attack.
Preventing Clots in Stents
To prevent such blood clots, cardiologists prescribe anti-clotting drugs such as clopidogrel (Plavix) or prasugrel (Effient), often in conjunction with aspirin, but they haven’t known how long patients should continue on such medication. A large new study with nearly 10,000 patients in The New England Journal of Medicine attempted to resolve this thorny problem, since such drugs can produce serious side effects.
Some patients were assigned to receive their anticoagulant for 30 months, while others (no one knew which) were given a placebo anticoagulant instead after a year. Continuing on the dual therapy (anticoagulant plus aspirin) reduced the risk of clotting in the stent, but people were more prone to dangerous bleeding so it did not save lives. The death rate was slightly higher among those on anticoagulant therapy (2%) than among those taking placebo (1.5%).
