Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gentler Heart Surgery remains without signs of Dementia

05.12.2013
Aortic valve stenosis is the most frequent heart valve defect of older people in Europe.

For patients at high and excessive risk, transcatheter aortic valve implantation (TAVI) remains the only opportunity. However, this procedure often leads to a crumbling and spreading of valvular calcium deposits and consecutive occlusion of smallest blood vessels of the brain.

Conceivably, this so called “microembolisation”, could lead to impairment of mental performance. In a long-term study, cardiologists at the Heart Center of the Bonn University Medical Center were able to exclude significant cognitive impairment for the majority of patients undergoing TAVI.

Gerhard E. could not breathe right. His aortic valve was relevantly narrowed and hardly opened anymore. For the 83-year-old, who had already had prior cardiac surgery, the “state-of-the-art” surgical valve replacement utilizing extracorporal circulation was too risky. But without replacement of the valve, his prognosis would have been very poor.

Consequently, Prof. Dr. Georg Nickenig, Chair of the Department of Cardiology of the Bonn University Medical Center, who weighed the risks and benefits together with Prof. Dr. Armin Welz, Chair of the Department of Cardiac Surgery, recommended transcatheter aortic valve implantation (TAVI) to Gerhard E. three years ago. "I was really happy and relieved that there was a second, gentler alternative for my father", his son says.

"However, even this technologically mature intervention, which requires a sophisticated apparatus, is associated with some risks" Prof. Nickenig knows. Small particles of valvular calcium deposits can be mobilized during the procedure and spread to the brain with the bloodstream. Hence, interventional and surgical replacement of severely calcified heart valves are associated with a stroke risk of approximately 2-5%.

"Mini-strokes" a risk to memory?

In contrast, the cognitive performance level, such as intellectual function, memory, orientation, and concentration of the patients, had not yet been studied over the long term following implantation of an aortic valve. "However, this is of great importance in the ability of our elderly patients to cope with everyday life and to retain their independence, in particular considering the rising life expectancy"; that is how Privatdozent Dr. Alexander Ghanem, Senior Physician at the Department of Medicine II of the Bonn University Medical Center describes his motivation to conduct such a study. With this in mind, he prospectively investigated 125 high-risk patients – including Gerhard E. He recently published the results in the well-known technical journal "Circulation: Cardiovascular Interventions".

In cooperation with the Department of Radiology of the Bonn University Medical Center, using MRI exams of the brain following aortic valve implantation, he very frequently observed “microembolism” in the patients’ brains – as a result of spreaded calcium deposits from the heart valve that were transported into the brain. The question arises whether clinically silent "microembolism" could be associated with the later occurrence of dementia spectrum disorders. Thus, in collaboration with the German Center for Neurodegenerative Diseases (DZNE) in Bonn, Ghanem tested and compared the cognitive capacity and memory capacity of patients before and after the intervention: "More than 90 percent remained consistently unharmed in this respect throughout two years after valve implantation".

Microembolic events had no influence on mental performance

On the other hand, elderly patients with aortic valve stenosis often have restricted cognitive capacity prior TAVI – possibly due to a narrowed aortic valve, leading, among other things, to inadequate blood supply in the brain. "Happily, even patients markedly below average cognitive performance prior the intervention had no significant decay of cognitive and mental performance levels for up to two years after the intervention. Consequently, the mental capacity even of these patients is not negatively impaired by aortic valve implantation", says Ghanem.

And also not for Gerhard E., who is still delighted with the intervention three years ago: "My son and I often go for a walk. The exercise is good for me", says the 83-year-old.

Publication: Cognitive Trajectory After Transcatheter Aortic Valve Implantation, Circulation: Cardiovascular Interventions 2013 Oct 15; DOI: 10.1161/CIRCINTERVENTIONS.112.000429

Contact:
Privatdozent Dr. Alexander Ghanem
Senior Physician, Department of Cardiology
Heart Center of the University of Bonn
Bonn University Medical Center
Telephone: +49 228/287-15507
E-Mail: ghanem@uni-bonn.de

Dr. Inka Väth | idw
Further information:
http://www.uni-bonn.de

More articles from Health and Medicine:

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

nachricht Direct conversion of non-neuronal cells into nerve cells
03.07.2018 | Universitätsmedizin der Johannes Gutenberg-Universität Mainz

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

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

13.07.2018 | Event News

Research finds new molecular structures in boron-based nanoclusters

13.07.2018 | Materials Sciences

Algae Have Land Genes

13.07.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>