Cardiac optogenetics achieve defibrillation without the pain of electric shocks
Barcelona, 4 July 2014: The first evidence for a shockless treatment for atrial fibrillation (AF) will be presented today at Frontiers in CardioVascular Biology (FCVB) 2014 in Barcelona, Spain. The meeting is organised by the Council on Basic Cardiovascular Science of the European Society of Cardiology (ESC) in collaboration with 13 European cardiovascular science societies. http://spo.escardio.org/Session
This is the logo for FCVB 2014.
Dr Brian O. Bingen, first author, said: "AF is the most common cardiac arrhythmia. Symptoms range from the feeling of fish flapping in the chest, to tiredness and exercise intolerance. AF can lead to tachycardia induced cardiomyopathy and thromboembolic events which increase the risk of morbidity and death."
He added: "Preventing these symptoms and complications requires bringing the patient out of AF and back to the normal sinus rhythm. The quickest way to do that is to deliver an electric shock. The shock depolarises and synchronises the heart muscle and allows the sinus node to re-establish a normal rhythm."
Dr Bingen continued: "Shocks are currently the most effective way to get patients directly back into sinus rhythm but they are very painful. To deliver a shock you have to give anaesthesia which comes with its own possible adverse effects."
AF usually progresses from a paroxysmal form, in which episodes of AF last from several minutes up to 7 days, to a persistent and eventually a chronic form. People with the latter are in AF 24 hours a day, 7 days a week, and shock treatment no longer works. Dr Bingen said: "AF causes structural changes to the atrium which make patients more prone to subsequent induction of AF. That's another reason to get patients back into sinus rhythm as soon as possible."
For the current study, the researchers devised a method of shockless defibrillation. They used optogenetics to genetically insert depolarising ion channels into the heart that can be activated by light. Dr Bingen said: "The theory was that we could just turn a light switch on and depolarise the entire myocardium without needing a shock. In theory, the patient could be given an implantable device with a mesh of light emitting diodes (LEDs) and when AF occurs you turn the light on and the AF stops."
During arrhythmias there is activity subepicardially but the heart is a complex 3D structure and it is only possible to directly observe the epicardium (outside layer). To see how their method worked subepicardially, the researchers developed 2D hearts. They isolated cardiac muscle cells from the rat atrium, replated them in a culture dish and allowed the cells to form intercellular connections, creating a 2D heart.
AF was induced in 31 of these 2D hearts. The researchers used a lentivirus to insert a gene into the 2D hearts called calcium-translocating channelrhodopsin (CatCh), which is a light sensitive depolarising channel.
Dr Bingen said: "Then it was just a matter of switching on the light and seeing what happened. We found that in all 31 of these 2D hearts we were able to achieve the 2D equivalent of cardioversion into sinus rhythm. The mechanism we saw was a bit different than the normal defibrillation but was equally effective."
He continued: "We now have to test our method in the 3D setting. In that scenario we won't be able to see the defibrillating mechanism in as much detail, but we hope that it will be possible to terminate AF in the complete heart. We will also test other types of light or energy sources that penetrate the body more deeply and could be applied externally, avoiding the need for an implanted device."
Dr Bingen continued: "This is the first evidence of a shockless defibrillation. Our method of using optogenetics to defibrillate by light is completely painless and looks promising but more research is needed before it can be applied in patients."
Please note Spanish version is available for this Press Release
Note to Editors
Frontiers in CardioVascular Biology (FCVB) is a comprehensive basic science conference organised every two years by the ESC Council on Basic Cardiovascular Science, whose mission is to enhance the importance of basic science to clinical cardiology. FCVB 2014 was organised in collaboration with 13 European cardiovascular science societies.
About the European Society of Cardiology (ESC)
The European Society of Cardiology (ESC) represents more than 80 000 cardiology professionals across Europe and the Mediterranean. Its mission is to reduce the burden of cardiovascular disease in Europe.
Information for journalists attending FCVB 2014
ESC Press Office - Alice Prieto
Tel: +336 22 41 84 92 (off site support number)
Please note that this year the ESC Congress 2014 will also take place in Barcelona, at FIRA Gran Via from 30 August – 3 September 2014. http://www.escardio.org/congresses/esc-2014/Pages/welcome.aspx
You can already register on-line as press: http://www.escardio.org/congresses/esc-2014/registration/Pages/press-registration.aspx
On-site Press registration process:
Contact: ESC Press Office
Tel: +336 22 41 84 92
ESC Press Office | Eurek Alert!
Plants are networkers
19.06.2017 | Institut für Pflanzenbiochemie
Digital Survival Training for Executives
13.06.2017 | NIT Northern Institute of Technology Management gGmbH
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...
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...
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...
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...
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)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
27.06.2017 | Power and Electrical Engineering
27.06.2017 | Information Technology
27.06.2017 | Physics and Astronomy