Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bone and cartilage growth to blame for heart valve disease

13.04.2006


Northwestern researcher’s study points to active rather than passive process

Research to be published in the April 18 issue of the Journal of the American College of Cardiology provides the first explanation of an active rather than passive process that leads to heart valve degeneration, furthering a Northwestern researcher’s effort to lead a paradigm shift in the medical community’s beliefs about the cause of valve disease.

Heart valve disease is caused not by a ’wear and tear’ phenomenon, but by an inflammatory process likely triggered by high cholesterol that stimulates certain cells to reprogram into bone cells in the aortic valve and cartilage cells in the mitral valve, says principal investigator Nalini Rajamannan, MD, newly appointed director of the Center for Heart Valve Disease in the Bluhm Cardiovascular Institute of Northwestern Memorial Hospital and assistant professor of medicine, Northwestern University Feinberg School of Medicine, who examined diseased mitral and aortic valves removed during surgery for the study.



"Common wisdom in the medical community has always been that thickening of the mitral valves was part of the aging process as deposits of calcium, a mineral found in the blood, built up on the valves. Therefore, research has never focused on preventing the problem," says Dr. Rajamannan. "Currently the only option is to surgically repair or replace the damaged valves. Our findings open the door to the idea that medical therapies such as statins may be able to play a role in preventing or slowing the process and curtailing the need for surgery."

Valvular heart disease is on the rise with the aging of the United States population, and is second only to coronary artery disease as a cause for open heart surgery. Heart valve disease leads to 100,000 surgeries in the U.S. each year to repair or replace damaged valves. Mitral valve disease is a leading cause of atrial fibrillation, which is a major culprit in strokes and heart failure. Aortic valve disease can lead to heart failure, arrhythmia, infections in the heart, and sudden death may occur in 15 to 20 percent of people who have symptoms.

Dr. Rajamannan has focused her research for the past seven years on advancing the knowledge of mechanisms of aortic and mitral valve disease using animal models and human studies. "I wanted to know why diseased valves had were hardened with a glassy whitish appearance – totally different than healthy tissue, which indicated to me that the actual structure of the valves had changed," she says. Dr. Rajamannan has been awarded over $750,000 in grants from the NIH and the American Heart Association to pursue this research.

Dr. Rajamannan’s laboratory was the first to treat animals with calcifications in heart valves with medications called statins, the same drugs that are currently used to treat high cholesterol. In an early pioneering study, animals treated with statins had significantly less heart valve disease than the control animals that were not treated. The results from the animal studies and now with the human valves demonstrate that valvular heart disease has an active biology which can be treated with medications similar to that of coronary artery disease.

The current wisdom is that mitral valve insufficiency (leaking of the valve) was caused by degenerative changes over the course of time – more or less, wear and tear. Dr Rajamannan’s unique observations indicate that the process of valve degeneration is instead an active process, linked to inflammation and cellular growth, that shares similar risk factors to hardening of the arteries (atherosclerosis).” says Robert Bonow, MD, co-director of the Bluhm Cardiovascular Institute. “This suggests that there may be medical treatments in the future that could either treat this condition or prevent it from developing.”

This research was completed with the support of an American Heart Association Grant-in-Aid (0350564Z) and a grant from the US National Institutes of Health (1K08HL073927-01).

Dr. Rajamannan’s research will be featured at the American College of Cardiology’s 2006 Heart Valve Summit being held June 15-17 in Chicago, which will bring together several of the world’s leading cardiologists and cardiac surgeons to provide a comprehensive review of recent advances in the treatment of valvular heart disease.

Amanda Widtfeldt | EurekAlert!
Further information:
http://www.nmh.org

More articles from Health and Medicine:

nachricht Vanishing capillaries
23.03.2017 | Technische Universität München

nachricht How prenatal maternal infections may affect genetic factors in Autism spectrum disorder
22.03.2017 | University of California - San Diego

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: 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...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

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

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>