Electrical waves are crucial to heart cell communication and maintaining rhythm. Now, scientists have found that light can be used to intricately control these electrical waves, providing more insight into how the heart works and a potentially less invasive and more precise treatment for heart conditions.
The electrical signals that travel between heart cells are called excitation waves, and a team of researchers from Stony Brook and Oxford Universities developed a way to project light patterns onto heart tissue to change the way the waves move.
For example, in a cardiac arrhythmia, which is a potentially dangerous abnormal heart rhythm, the excitation waves swirl around at high frequencies, like a tornado.
Currently, patients are treated with a high-energy shock to terminate and restart the electrical signaling, like hitting the restart button on a computer.
“Instead of the brute force of resetting the heart, we can use light to redirect the waves in a much more elegant way,” said Emilia Entcheva, a Stony Brook University biomedical engineering professor and co-author of the study. “We can use light to take this spinning tornado and move it around and change its direction, which is a new level of manipulation of arrhythmia-causing waves in the heart.
This type of wave steering has never been demonstrated before in any cell type. The team used gene therapy and computer programming to apply the technique, called optogenetics, to heart cells.
First the cells were sensitized to light through genetically expressing channelrhodopsin. Then, the team developed a light projector that was computer programmed and could be used to stimulate, alter and move the excitation waves.
In the short term, this system can be used as a basic sciences tool to better understand heart conditions and how excitation waves are formed and terminated. Additionally, the technique can be applied to observe heart cell responses to drugs that are being developed.
In the long term, the goal is to the use this technology to create more specific and less harmful treatments for heart conditions.
The team is currently working to expand the methodology and has been able to successfully use it in adult rats.
However, the team still faces significant challenges to reach their goal of human applications, such as developing a safe way to deliver the gene therapy and creating technology to direct the light only to specific regions of the heart.
“I find biological problems to be the most challenging and complex to solve because there is a lot of variability and a lot of unknowns,” Entcheva said. “It’s the ultimate complex system, very challenging but also rewarding when you can actually solve a problem.”
Correction: Oct. 31, 2015
A previous version of this story erroneously reported that Emilia Entcheva was the lead author of the study on the use of light to control heart excitation waves. Entcheva was a co-author, not the lead author.
Featured Image Credit: Aleks Klimas