We’ve covered various treatments of clogged heart arteries previously, and there is no question that heart stents have saved countless lives in the short term by preventing impending heart attacks or opening arteries while an attack is being treated. However drug eluting stents may result in the incident of what is known as stent thrombosis, or the formulation of a blood clot within the stent itself. While the drug eluting stent is time-releasing its drugs, it effectively stops the re-growth of muscle cells inside the stent. This results in a clot which in turn results in a heart attack.

Neither type of stent, bare metal stents nor drug eluting stents have been shown in rigorous clinical trials to improve long-term survival compared with open heart bypass surgery. In December 2006, an expert FDA panel concluded that drug-eluting stents are even more likely than bare-metal stents to cause thrombosis.

Stents, which come in varying sizes and designs, are inserted by a cardiologist though a small opening, typically in the leg. The stents are then snaked to the heart on a microscopic balloon that opens the artery and is removed after the stent is in place.

With bare metal stents, the main drawback is the tendency of the repaired artery to become clogged again (restenosis). Drug eluting stents can cut restenosis in half, but have now been found to carry their own dangerous risks - which in some cases may even prove fatal.

For people who receive drug-coated stents, the standard protection against clotting is what is known as “anti-platelet therapy” - a few months of aspirin and the blood-thinner drug Plavix. Problem is, aspirin is a known stomach irritant and Plavix causes severe rashes and bruising. To prevent the recurrence of clotting, the FDA recommends staying on Plavix for a year, and on aspirin forever.

Why have stents become so popular? Probably because drug eluting stents are less invasive and frightening than full-scale surgery. They also help avoid the potential side effects of heart drugs, which can include fatigue, sexual dysfunction, depression and light-headedness. Perhaps other patients are not being told that a bypass surgery may be a good option.

Recent studies have shown that bypass surgery could extend many patients’ lives longer than stents. Stents, when improperly used, might put patients at greater risk of blood clots, heart attacks or even death. Bypass surgery should be considered as a better, longer term alternative.

Sources:

• Duke University: Drug-Coated Stent Patients at Risk if Anti-Blood-Clotting Medication Discontinued
• Duke University: Coronary Stents Do Not Improve Long Term Survival
• The Mobile Register (Alabama) : Doctors debate risk, benefits of stents - Fred Tasker; July 3rd, 2007
• The Wall Street Journal: New studies hint at overuse of stents - Ron Winslow; January 23rd, 2007
• MSNBC.com : Some heart stents pose death risk;March 1st, 2007
• The New York Times: Doctors Rethink Widespread Use of Heart Stents - Barnaby J. Feder; October 21st, 2006.

1960s: Coronary artery bypass grafting surgery (CABG) is introduced to repair arteries clogged with plaque. Surgeons harvest healthy veins from a patient’s legs and transplant them around blocked arteries near the heart, restoring blood flow.

The problem: Although effective, it’s a major operation. Surgeons saw through the patient’s sternum and pry open the rib cage. About 500,000 such surgeries a year are performed.

1977: Doctors begin to unclog arteries with balloon angioplasty. They make a small slit in the patient’s groin, run a wire-like catheter up the femoral artery and inflate a tiny balloon inside the plaque blockage, opening it, restoring blood flow.

The problem: Within six months, one-third to one-half of patients experience a re-narrowing of the artery due to plaque, called “restenosis.”

1986: Pharmaceutical companies bring out the “bare-metal stent” a tiny metal-mesh sleeve that is collapsed, run up the femoral artery to the plaque lesion, expanded by the balloon and left to keep the artery open.

The problem: In 15 percent to 30 percent of cases, restenosis still occurred within a year.

The reason: Ideally, when a wire-mesh is implanted, the artery heals it over in a few months with smooth muscle cells called endothelia. But in some cases, the cells grow back too aggressively, piling up into scar tissue, narrowing the artery again and encouraging a new blockage with plaque.

2003: The “drug-eluting stent” arrives. It’s coated with medicine that is released over a month or more to slow the growth of the cells that encourage restenosis. They were a hit - cutting re-blockage by two-thirds.

The problem: Occasionally a patient with a drug-eluting stent suffers a heart attack, and sometimes it’s fatal. Studies say it happens more often with drug-eluting stents than with bare-metal stents. It isn’t restenosis; it’s thrombosis, a sudden blood clot that forms inside the drug-eluting stent.

The reason: While the drug-eluting stent is time-releasing its drugs, it effectively stops the re-growth of muscle cells inside the stent.Thus, the bloodstream reacts to the foreign metal object - the bare stent - the same way the blood in your cheek reacts to the nick of a razor - it clots. Result: a heart attack.

Today the debate rages on; doctors in favor of creating better stents vs. doctors who would forgo angioplasty altogether in favor of open-heart surgery.

Sources: Fred Tasker - McClatchy Newspapers, Ohio.com

That depends on whom you ask, and what studies you cite. Conventional cardiology wisdom has long held that heart attacks occur because arteries blocked by the buildup of plaque starve the organ of blood, sending it into a condition called infarction. Under that model, angioplasty, stenting (placing of a wire mesh structure in the blood vessel) and bypass surgery all make a certain amount of sense.

Angioplasty lets doctors thread a snake-like device with a balloon on the end into diseased and narrowed arteries. Inflating the balloon opens the blockage. Usually, cardiologists will leave behind one or more tiny metal scaffolds, called stents, as insurance.

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