Drug Coated Stents and Heart Surgery: DES Lawsuit
Coronary stents, and drug coated stents in particular, have revolutionized the treatment of heart disease yet not without problems. New techniques and materials that lessen these problems are currently being researched.
Heart blockage is caused by cholesterol clogging plaque which leads to shortness of breath and chest pains called angina. If the artery closes completely, the result is a heart attack with destruction of the heart muscle often leading to death.
Beginning around 1980, doctors started using tiny balloons inserted on wires through the veins and guided by X-rays to push open the clogged arteries. This procedure, called angioplasty, often worked — but not without a problem. In about 50 percent of the cases, the artery would close up again within a few weeks or months. This outcome is called restenosis. The re-shutting of the arteries occurs because the blood vessels respond to the treatment as if they suffered a slight wound. They try to heal by growing more cells which can clog the artery again.
In order to solve the problem around 1994, cardiologists put tiny pieces of wire mesh called stents around the balloons. These stents remain in place as a piece of scaffolding by trying to keep the arteries open. These early stents helped – up to a point. Cells still grew over the wire mesh. In 20 to 30 percent of the cases, the vessel clogged again.
The next solution was drug-eluting stents (DES) which is also known as drug coated stents. These stents give off a drug that prevents cell growth. The cell blockage or restenosis rate fell to about 5 percent. In 2003, soon after the FDA approved DES, drug-eluting stents captured most of the market, even though they cost about $2,000 compared to $800 for the bare metal version.
Then a new problem appeared: Doctors began seeing patients suffer from heart attacks that seemed to be triggered by the new stents. Because the drug-eluting stents are so effective at stopping the cell proliferation inside the arteries, the drug coated stents end up as a piece of metal sticking out in the artery which creates a perfect place for a blood clot to form and instantly block the artery. Unfortunately, this results in a potentially fatal heart attack.
Based on DES clinical studies, the danger of a blood clot is estimated at 1 in 500 patients per year. For every million of the DES devices implanted, that would be up to 2,000 blood clots a year. However, not every blood clot will be fatal.
The American College of Cardiology’s Web site estimates that deaths from new DES devices exceed 2,000 a year. Studies from Europe regard the danger to be much higher. Because the DES devices are so new, no one knows the depth of the problem or its real probability which is frightening.
Currently, many cardiologists are cutting back from using the DES devices; sales are plummeting. The FDA panel may well recommend they not be used at all.
Companies are researching alternatives, including balloons that give off the drugs and would be removed at the time of the procedure, as well as, stents that dissolve a few weeks after being implanted.
The next big question facing the FDA is: What should the estimated 4 million patients who already have a drug coated stent do?
The devices cannot be removed safely or easily. One preventive measure is to keep the patient on the blood-clotting medication Plavix for months or even indefinitely. But that medicine can cause severe bleeding, including a type of deadly stroke, and Plavix costs more than $1,200 a year.