Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers uncover genetic link to stroke after heart surgery

29.08.2005


Duke University Medical Center researchers have discovered that patients who have two specific gene variants are more than three times as likely to suffer a stroke after heart surgery.



Furthermore, since the two implicated genes are involved in the body’s immune response to insult or injury, the researchers said that their findings strongly suggest that inflammation plays an important role in post-operative stroke.

The researchers said that if the findings are confirmed by more extensive studies, they could become part of a battery of genetic tests to better identify the risk to patients of stroke after surgery.


"Despite all our advances in improving outcomes after cardiac surgery over the decades, stroke remains a significant and debilitating complication," said Duke cardiothoracic anesthesiologist Hilary Grocott, M.D., whose study results were published early on-line in the journal Stroke. The study was supported by the National Institutes of Health and the American Heart Association.

"As the population of patients getting cardiac surgery continues to age, it is important for us to better understand all the factors that impact mortality and the quality of life for these patients," he continued. "Discovering that these two genes are linked to stroke after heart surgery is an important first step that should now be validated by larger studies."

While it is still too early to change clinical practice based on the findings of the Duke team’s findings, Grocott said that in the not-too-distant future physicians will be better able to define a specific patient’s risk for adverse outcomes after heart surgery based on a spectrum of genetic and clinical information.

"When discussing the risks and benefits of surgery, it is important to patients to know whether they are at a higher or lower risk," he said.

For their study, the researchers selected 26 genes implicated in past non-surgical studies as possibly playing a role in the incidence of stroke. The genes identified regulate three general processes – coagulation, inflammation and lipid metabolism.

After identifying the candidate genes, the researchers then consulted a databank of 1,635 patients enrolled in an ongoing Duke study on the role of genetics in cardiac surgery outcomes. Of those patients, 28 (1.7 percent) suffered a stroke after surgery. Nationally, the reported incidence of stroke after heart surgery is approximately two percent but can vary widely, Grocott said.

The researchers then analyzed blood samples to determine whether specific variants, known as polymorphisms, of the 26 candidate genes, either alone or in various combinations were associated with stroke.

While they found that no individual polymorphism was linked to stroke, the team did find that patients with a specific combination of polymorphisms in genes responsible for the production of C-reactive protein (CRP) and interleukin-6 (IL-6) suffered stroke at more than a three times higher rate. CRP is a protein released into the bloodstream as a natural reaction to infection, fever or other injury, while IL-6 is a protein that regulates the intensity of the immune response.

Of the patients enrolled in the study, 36 percent had the polymorphism pair in question – 3.09 percent of those patients suffered a stroke, while only 0.95 percent of patients without the pair suffered a stroke.

"We know that a patient’s genetic makeup plays a major role in so many diseases, there’s no reason to believe that cardiac surgery is any different," Grocott said. "We also know that cardiac surgery is one of the biggest pro-inflammatory stimuli known, so the fact that inflammation is involved is not surprising."

While the role of inflammation was not surprising, Grocott said the team found it significant that they found no links to genes involved in the blood coagulation pathway. "To see these patients get strokes without a thrombotic polymorphism is somewhat of a novel finding in itself," he continued.

Grocott said that since this polymorphism pair appears to be present in more than one-third of the population undergoing heart surgery, further study is needed not only to better understand the underlying mechanisms involved but to determine if new approaches to minimize the inflammatory response in patients identified at high risk could impact outcome.

Two earlier Duke studies this year have found genetic links to other adverse outcomes after cardiac surgery. One study found polymorphisms linked to kidney damage after heart surgery (http://www.dukemednews.org/news/article.php?id=8428), while another study uncovered polymorphisms that can help predict which patients are more likely to suffer bleeding episodes after heart surgery (http://www.dukemednews.org/news/article.php?id=8658).

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

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

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

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>