Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New treatment for severe aortic stenosis shown to save lives

23.09.2010
Implantation of a new bioprosthetic-tissue valve into the hearts of patients who have severe aortic stenosis and are too sick or too old for open-heart surgery has been found to both save lives and improve the quality of those lives, according to a new multicenter study, to be published online at 2 p.m. Pacific time today in the New England Journal of Medicine.

The study will also be presented at 8 a.m. Pacific time at the Transcatheter Cardiovascular Therapeutics Conference in Washington, D.C. on Sept. 23.

"This is exciting because it does save lives and is a major medical paradigm shift," said D. Craig Miller, MD, the Thelma and Henry Doelger Professor of Cardiovascular Surgery at the Stanford University School of Medicine and one of the manuscript's principal authors. "These patients were really sick with a fatal problem, and now they're feeling better and staying out of the hospital. Before, there was nothing we could really offer them."

Stanford University Medical Center was one of 21 institutions to participate in the study, known as the PARTNER Trial. It is the first randomized clinical trial comparing the efficacy of using a transcatheter heart valve called "TAVI" - which is implanted percutaneously through an artery in the groin directly into the beating heart - with routine medical therapy, which includes aortic balloon valvuloplasty to relieve symptoms. The trial was sponsored by Edwards Lifesciences Corp., based in Irvine, Calif., which designs, manufactures and markets tissue heart valves.

A total of 358 patients with severe aortic stenosis, a heart disease characterized by obstruction of the aortic valve due to calcification, participated in the trial. The patients who qualified were debilitated by the disease, which causes shortness of breath, fatigue and congestive heart failure. While the standard of care for most patients with this condition would be open-heart surgery to replace the diseased valve, that was not a realistic option for the specific patients selected for this study, who were too sick or too old to undergo such an operation. For them, the standard of care is medical therapy.

At one year after randomization, 30.7 percent of patients who had received the percutaneous valve replacement had died compared with 50.7 percent of those who received standard medical therapy.

"The most impressive finding in the study is the 20 percent reduction in mortality," said William Fearon, MD, associate professor of cardiovascular medicine at Stanford, who also participated in the study. "This is very dramatic. The effect was so powerful that by just treating five people you can save one life. But beyond just the survival benefit, the improvement in the patients' quality of life based on their symptoms and their ability to exercise is dramatic."

Stanford enrolled more than 80 patients in the PARTNER study, of which 14 were these very sick patients. Jana Pausa, 76, of Atherton, Calif., who had both severe aortic stenosis and lung disease that made her unsuitable for open-heart surgery to replace the diseased heart valve, is one such patient.

"Getting dressed or anything was absolutely debilitating," said Pausa, who was randomized to have the device implanted a year and a half ago. "Before the surgery, I used a walker. Sleeping was difficult because I didn't feel like I could breathe. I had no energy. When I woke up out of surgery, I immediately felt the difference. I could breathe - for sure it saved my life."

Now she's walking and playing with her grandchildren and planning for her husband's 80th birthday party.

Many patients with severe aortic stenosis come into the hospital in a wheelchair, said Alan Yeung, MD, the Li Ka Shing Professor of Medicine and chief of Stanford's division of cardiovascular medicine, who was also involved in the study. "Nobody thinks they're going to walk out of the hospital. These patients are now able to go shopping, to spend time with their family. People can have a good quality of life."

The study did show though that patients paid a price for the procedure, Miller said. Patients who had the device implanted suffered higher rates of stroke: 5 percent vs. 1 percent. They also had more major vascular complications - 16 percent vs. 1 percent - and bleeding due to the size of the catheter.

Future studies are planned to determine the durability of the TAVI valves and also to determine whether this procedure may be beneficial in other lower-risk and younger patients for whom open-heart surgery is a low-risk and durable option.

The trial used the Edwards SAPIEN valve, which costs about $20,000 but is not yet commercially available in the United States and does not have approval from the U.S. Food and Drug Administration. The valve is made of a stainless-steel stent and cow pericardium.

The procedure, which takes about two hours, involves inserting a catheter (or tube) through the femoral artery in the groin. In this TAVI approach, the catheter travels up the aorta to the heart and crosses the severely stenotic aortic valve, where the new valve is deployed. The entire concept, starting with patient selection, is a major team effort; the interventional cardiologists and cardiovascular surgeons work together with cardiac anesthesiologists and a cardiologist echocardiographer throughout the procedure using fluoroscopy and transesophageal echocardiography to guide the valve positioning and deployment without cutting the chest open.

The prosthetic heart valve is collapsed down over a balloon over the catheter. After it's been positioned precisely across the diseased aortic valve, the balloon is inflated with saline and the valve expands, crushing the diseased valve and enabling the heart to pump blood to the body much more effectively.

No financial interests were reported by Stanford participants in Edwards Lifesciences. As an author of the study, Miller reported receiving consulting fees from the other medical technology companies, Medtronic and St. Jude Medical.

Additional Stanford faculty and staff on the PARTNER team included cardiovascular surgeon Michael Fischbein, MD; cardiologist David Liang, MD, PhD; cardiovascular anesthesiologists Pieter van der Starre, MD, PhD; and Charles Hill, MD; and nurse coordinators Martina Speight and Cheryl McWard.

The Stanford University School of Medicine consistently ranks among the nation's top medical schools, integrating research, medical education, patient care and community service. For more news about the school, please visit http://mednews.stanford.edu. The medical school is part of Stanford Medicine, which includes Stanford Hospital & Clinics and Lucile Packard Children's Hospital. For information about all three, please visit http://stanfordmedicine.org/about/news.html.

Tracie White | EurekAlert!
Further information:
http://www.stanford.edu

More articles from Health and Medicine:

nachricht TSRI researchers develop new method to 'fingerprint' HIV
29.03.2017 | Scripps Research Institute

nachricht Periodic ventilation keeps more pollen out than tilted-open windows
29.03.2017 | Technische Universität München

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>