Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Coronary stents do not improve long-term survival

08.11.2004


While the placement of stents in newly reopened coronary arteries has been shown to reduce the need for repeat angioplasty procedures, researchers from the Duke Clinical Research Institute have found that stents have no impact on mortality over the long term.



In the largest such analysis of its kind, the Duke researchers said their findings have important economic and clinical implications for physicians who are deciding whether their heart patients should receive coronary artery bypass surgery, or less-invasive angioplasty, which includes the placement of a stent.

Stents, which were introduced in the U.S. in 1994, are tiny mesh tubes that are inserted at the site of a blockage in a coronary artery that has been opened during balloon angioplasty. The procedure seeks to prevent the artery from becoming blocked again, a process known as restenosis. These blockages, caused by atherosclerotic plaque, can starve the heart of oxygen-rich blood and lead to a heart attack.


Duke cardiologist David Kandzari, M.D., who presented the results of the Duke analysis Nov.7, 2004, at the American Heart Association’s annual scientific sessions in New Orleans, said the findings on mortality rates should also be expected to hold true for the latest generation of drug-eluting stents. These stents, which were introduced in 2003, are coated with a drug that keeps blood clots from forming inside them. "We have found in our long-term analysis that stents do provide a significant early and sustained reduction in the need for subsequent procedures to re-open the treated artery," Kandzari said. "However, we also found that stents do not have any influence on long-term survival.

"Since earlier studies have shown that new drug-eluting stents can lessen the incidence of restenosis, we would expect the need for repeat procedures to decline even more as these stents become more widely used," Kandzari continued. "While earlier trials of drug-eluting stents have demonstrated a significant reduction in repeat procedures, they still have shown no differences in mortality compared with more conventional stents."

Specifically, the researchers found that over the average seven-year follow-up period of their study, 19 percent of patients who received a stent needed another revascularization procedure in the treated artery, compared to 27 percent for those who did not receive a stent. However, the long-term mortality rate for those receiving a stent was 19.9 percent vs. 20.4 percent for those who did not, a disparity which did not statistically differ.

For their analysis, the researchers consulted the Duke Database for Cardiovascular Disease, which keeps detailed clinical data on all heart patients receiving treatment at Duke. The researchers identified 1,288 matched pairs of patients who underwent either balloon angioplasty alone or stenting -- yet all had a similar likelihood of receiving a stent based on their clinical and demographic characteristics.

The patients, 63 percent of whom were male and who had an average age of 59 years, were treated between 1994 and 2002. One in four was diabetic, and one in four had suffered a previous heart attack. "This study, based as it is on a real-world population of patients, tells us that stents do not save lives, though they do have a profound effect on avoiding repeat procedures," Kandzari said. "We’ve know that restenosis has never been scientifically associated with increased mortality, but it has been associated with an increased need for revascularization and with a reduction in symptoms such as chest pain."

Given these findings, Kandzari said physicians treating their heart patients should not automatically assume that placing a stent, whether the original bare-metal type or the newer drug-eluting version, will be the end of treatment. "Many physicians will successfully place a stent and think that’s it," Kandzari continued. "The bigger issue is that many of these physicians should also then be prescribing drugs that have a clearly demonstrated beneficial effect on long-term mortality."

Kandzari plans to follow up this study with a similar analysis of the effects of the drug-eluting stents on mortality. Also, the team plans to measure any differences in the quality of life of these patients. "As we take on more and more difficult and complicated cases in the catheterization lab, we should take a step back to see if there are certain instances when bypass surgery may be the best option," Kandzari said. "There is the temptation out there to just place stents in all patients, no matter what. In some prior trials, the difference in outcome between angioplasty and surgery patients was driven by restenosis, not by differences in mortality.

"However, in the era of conventional stenting, we knew that there we still some instances in which bypass surgery might provide an incremental survival benefit," Kandzari said. "Before routinely placing drug-eluting stents in similar patients, these findings underscore the need for systematic evaluation of drug-eluting stents in these types of patients." Patients with left main coronary artery disease, for example, appear to fare better with bypass surgery than with angioplasty and stents. Previous study has also suggested this may be true for diabetic heart patients with extensive disease, who appear to benefit the most from bypass surgery, Kandzari said. "Appropriately, a trial is forthcoming to compare treatment with drug-eluting stents with bypass surgery in diabetic patients," he said.

The study was supported by the Cordis Corp., Miami Lakes, Fla., which develops stents. Kandzari has no financial interest in Cordis. Other members of the Duke team were Robert Tuttle, M.D., James Zidar, M.D., and James Jollis, M.D.

Richard Merritt | EurekAlert!
Further information:
http://www.mc.duke.edu

More articles from Health and Medicine:

nachricht Why might reading make myopic?
18.07.2018 | Universitätsklinikum Tübingen

nachricht Unique brain 'fingerprint' can predict drug effectiveness
11.07.2018 | McGill University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Global study of world's beaches shows threat to protected areas

19.07.2018 | Earth Sciences

New creepy, crawly search and rescue robot developed at Ben-Gurion U

19.07.2018 | Power and Electrical Engineering

Metal too 'gummy' to cut? Draw on it with a Sharpie or glue stick, science says

19.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>