Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Minimally invasive surgery for heart rhythm abnormality proven effective

19.10.2004


A minimally invasive approach to curing the most common heart rhythm abnormality, atrial fibrillation, takes half the time of the traditional surgical procedure but is equally effective, according to research at Washington University School of Medicine in St. Louis.



Results from the first reported clinical trial testing the procedure appear in the October issue of The Journal of Thoracic and Cardiovascular Surgery. "Our findings show that this technique is much easier to perform but works just as well as the more invasive approach," says principal investigator Ralph J. Damiano, M.D., the John Shoenberg Professor of Surgery and chief of cardiac surgery at the School of Medicine, and a cardiac surgeon at Barnes-Jewish Hospital. "This is very good news because it means more surgeons can perform the procedure and it will be applicable to virtually all patients with this irregular rhythm."

Atrial fibrillation affects more than two million Americans. Normally, electric signals trigger the synchronized contraction of muscles in the heart’s two upper chambers, the atria. During atrial fibrillation, a chaotic web of electric impulses spreads throughout the atria, causing the chambers to quiver rather than contract in unison. The result is a host of painful symptoms and significantly increased risk of heart attack or stroke. In fact, atrial fibrillation accounts for about 15 percent of all strokes in the United States.


Medications can alleviate symptoms in some patients, but they cannot cure the problem. In 1987, researchers at the School of Medicine led by James Cox, M.D., developed a surgical cure called the Cox maze procedure to control these erratic impulses. In this procedure, surgeons make small, strategically placed incisions in the atria. The slits generate scar tissues that serve as barriers, trapping abnormal electric signals in a "maze" of barricades. Only one path remains intact, guiding impulses to their correct destination.

With a success rate of more than 90 percent, the Cox maze procedure revolutionized the treatment of atrial fibrillation. However, it is technically difficult and therefore is not performed frequently. Surgeons also must temporarily stop the heart and use a heart-lung machine to take over the heart’s role of circulating blood in order to make the incisions. Not all patients, therefore, are healthy enough to endure the operation.

Damiano and his colleagues developed an alternative using two electrodes that pass a current through a section of heart tissue, heating and killing a thin band of tissue. This bipolar radiofrequency variation of the Cox maze procedure creates scar tissues that similarly block abnormal impulses responsible for atrial fibrillation.

Damiano’s team replaced most of the Cox maze incisions with lesions created using the new, less invasive approach in 40 consecutive patients treated for atrial fibrillation at Barnes-Jewish Hospital from January 2002 to October 2003.

Overall, the success of the procedure was equivalent to the team’s success using the traditional Cox maze approach between January 1988 and January 2002. All patients survived the operation, and about 15 percent needed a pacemaker after surgery to help maintain a normal heart rhythm. A little over 90 percent of patients followed for six months still had healthy heart rhythms.

The only notable difference between the patients in this study and their predecessors who had undergone the traditional surgery was the length of the operation. Traditional Cox maze procedures took, on average, 93 minutes to perform, while procedures that incorporated the new approach took only 54 minutes. "Shorter operative times are important for patient safety and outcome," says Damiano. "If we shorten the procedure, it decreases the time we need to keep patients on the heart-lung machine. We are working in the laboratory on an approach that someday will allow us to perform atrial fibrillation surgery on the beating heart."

Gila Z. Reckess | EurekAlert!
Further information:
http://www.wustl.edu

More articles from Health and Medicine:

nachricht Correct connections are crucial
26.06.2017 | Charité - Universitätsmedizin Berlin

nachricht One gene closer to regenerative therapy for muscular disorders
01.06.2017 | Cincinnati Children's Hospital Medical Center

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Collapse of the European ice sheet caused chaos

27.06.2017 | Earth Sciences

NASA sees quick development of Hurricane Dora

27.06.2017 | Earth Sciences

New method to rapidly map the 'social networks' of proteins

27.06.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>