Angioplasty has become a life extending procedure for millions of Americans with heart disease since its introduction in 1987. While vessels could be opened through angioplasty by introducing an inflatable balloon to expand clogged arteries, the re-closure rate was high enough to suggest that a permanent fixture should be introduced to keep the vessels open at the point of critical narrowing. These devices, known as stents, were first studied in 1993, and by the end of the decade almost 85% of all angioplasty procedures employed the use of a stent, if not multiple ones.
A stent is a small metal band, or sleeve, that is placed within an artery to keep the vessel diameter open. In this current year it is estimated that over one million stents will be placed in the United States for those with critical occlusive heart disease. The stents were originally made of bare metal, and functioned as conduits over the diseased portions of the arteries.
Studies showed, however, that after time the repaired artery had a tendency to become clogged again. While the majority of stents remained open and facilitated blood flow cleanly through the heart, an increasingly significant complication was that the body still treated these as foreign objects, and inflammatory debris could accumulate and close the artery once again, a process known as restenosis.
Medication is taken by many heart patients to prevent blood clotting in the body and secondarily in the stents, and the logical thought was that stents that had anti-clotting medication (called drug eluting stents, or DES) would be more effective. Doctors began using these stents almost exclusively, until some 85-90% of stents placed in the cardiac vessels were drug eluting stents. Restenosis rates were greatly reduced, especially in the first month after surgery when they were previously the highest.
Recent studies however are finding that drug eluting stents actually pose a higher risk for patients of developing blood clots and re-stenosis months later- in fact significantly higher than the original metal stents. Delayed clotting within the stents is now beginning to even out the statistics and slow little if any difference in long term outcome between drug eluting and bare metal stents.
This is a significant finding, as drug coated stents cost almost three times what the bare metal ones do, and the recent data suggest that this risk of arteries re-closing is an additive and continual risk for patients even years after the surgery. It has caused doctors to rethink their positions on drug eluting stents. Another benefit of the newer stents was that they allowed patients to go without medication to keep their blood from clotting too rapidly. These medications carry significant side effects such as bleeding, severe rashes, easy bruisibility, and their cost (about $ 4/day) is not a negligible one.
A recent group of physicians is now advocating that perhaps stents are not always indicated in those with vessel closure, and that medication alone may provide the same benefit if an affected individual is not in the throes of a heart attack or within hours of active cardiac damage. This school of thought leans to using cholesterol lowering medications and drugs that enlarge arterial diameter over the immediate use of stents of either kind.
It is still early in the use of stent implantation and the research coming out of the original trials in the next 3-5 years will go a long way in defining their most appropriate use as well as whether stents should have medication, and if so which kind. In the meantime, trust in an experienced cardiologist is essential, and even then today’s answer may not be same months and years from now.
The information contained on this page is not intended to provide medical advice, which should be obtained directly from your physician.