OCT 17, 2016 7:08 AM PDT

To fix heartbeat, replace shocks with red light?

Image Credit: Martin Jakobson/Flickr

Beams of light can replace painful electric shocks to restore normal heartbeat in people suffering from potentially fatal arrhythmias, scientists now believe.

The findings, based on tests in animals and, separately, a computer model of a human heart, could pave the way toward implanting a new type of light-emitting defibrillator in patients.

“We are working towards optical defibrillation of the heart, where light will be given to a patient who is experiencing cardiac arrest, and we will be able to restore the normal functioning of the heart in a gentle and painless manner,” says Natalia Trayanova, a biomedical engineering professor who supervised a part of the research at Johns Hopkins University.
 

Today’s defibrillators deliver pulses of electricity that hurt and can also damage heart tissue. Light-based treatment would provide a safer and gentler remedy for patients at high risk of arrhythmia, an irregular heartbeat that can cause cardiac death within minutes.

The idea springs from advances in the field of optogenetics, in which light-sensitive proteins are embedded in living tissue, enabling the use of light sources to modify electrical activity in cells.

To move the proposed treatment closer to reality, scientists took different approaches.

A team from the University of Bonn in Germany conducted tests on beating mouse hearts whose cells had been genetically engineered to produce proteins that, when triggered by light, act to alter electrical activity in the organ. A one-second light pulse applied to a mouse heart in ventricular fibrillation was enough to restore normal rhythm.

“This is a very important result,” says Tobias Bruegmann at Bonn, a lead author of the study in the Journal of Clinical Investigation. “It shows for the first time experimentally that light can be used for defibrillation of cardiac arrhythmia.”

To find out if the technique could help human patients, the team at Johns Hopkins performed an analogous experiment, but not with a real heart. Their human “heart” was a detailed computer model derived from MRI scans of a heart attack patient now at risk for arrhythmia.

“Our simulations show that a light pulse to the heart could stop the cardiac arrhythmia in this patient,” says Patrick M. Boyle, a Johns Hopkins biomedical engineering research professor who was also a lead author of the journal article.
 
The illustration shows EKG readings before, during, and after the use of light-optogenetic defibrillation-to restore a normal heartbeat to an arrhythmic heart. (Credit: Patrick M. Boyle/JHU)

But researchers found that the process would need to be tweaked slightly for humans. The blue light used by the Bonn team in much smaller mouse hearts would not be powerful enough to fully penetrate human heart tissue. Red light, which has a longer wavelength, was more effective in the computer-based human tests.

This aspect of the study highlights the important role that computational modeling can play in guiding and accelerating the development of therapeutic applications for cardiac optogenetics, a technology that is still in its infancy, Boyle says.

More research is required before the promising technique can become a commonplace medical procedure, says Philipp Sasse, a junior professor at the Institute of Physiology I at the University of Bonn.

“The new method is still in the stage of basic research. Until implantable optical defibrillators can be developed for the treatment of patients, it will still take at least five to ten years.”

The study was supported by the German Research Foundation, the University of Bonn, and the US National Institutes of Health.

Source: Johns Hopkins University

This article was originally published on Futurity.org.
About the Author
  • Futurity features the latest discoveries by scientists at top research universities in the US, UK, Canada, Europe, Asia, and Australia. The nonprofit site, which launched in 2009, is supported solely by its university partners (listed below) in an effort to share research news directly with the public.
You May Also Like
MAR 12, 2020
Cardiology
MAR 12, 2020
Skipping Breakfast Increases Risk for Heart Disease Death by 87%
According to the old adage, ‘breakfast is the most important meal of the day’. But is that really so? Now, r ...
APR 06, 2020
Cardiology
APR 06, 2020
Positive Effects of Most Popular Diets Disappear After a Year
While evidence suggests that most diets lead to similar modest losses in weight and improvements in cardiovascular risk ...
MAY 04, 2020
Cardiology
MAY 04, 2020
Machine Learning May Help in the Diagnosis of Inherited High Cholesterol
Familial hypercholesterolemia, or FH, is an inherited genetic mutation in how the body recycles LDL cholesterol (bad cho ...
JUN 08, 2020
Cardiology
JUN 08, 2020
Long Working Hours Associated with Ischemia in Men
According to a recent study published in the Journal of the American Heart Association's Stroke, males who work ...
JUN 10, 2020
Cardiology
JUN 10, 2020
Aerobic Fitness Levels Associated with Weight Loss
According to a recent study at the American College of Physicians (ACP) Internal Medicine Meeting, improvements in aerob ...
JUN 25, 2020
Cardiology
JUN 25, 2020
Using RNA to Predict Acute Ischemic Strokes
Strokes are a leading cause of death and long term-disability across the globe. Ischemic strokes (IS) or acute ischemic ...
Loading Comments...