Advertisement

Light beams may replace electricity for heart disorder treatment

Optogenetic defibrillation corrected heart arrhythmia in beating mice hearts and human hearts in computer models, researchers report.

By Stephen Feller

WASHINGTON, Sept. 13 (UPI) -- The standard method of defibrillation involves sending powerful electrical pulses to the heart to correct irregular beats or restart a stopped heart, but researchers think they have a better method that is less painful and less damaging to the heart muscle.

Using optogenetics, researchers at Johns Hopkins University and the University of Bonn say electrical defibrillators could be replaced with ones delivering beams of light as a method of regulating the heart, according to a study published in The Journal of Clinical Investigation.

Advertisement

Optogenetics -- which involves embedding light-sensitive proteins in living tissue -- allows light sources to modify electrical activity in cells. Recent studies with mice have shown nerves in the brain, spinal cord and limbs can be stimulated using light and that memories thought lost can be reactivated using light, suggesting optogenetics has potential for medical application.

Heart patients with arrhythmia often have defibrillators implanted in their hearts to detect and deliver electrical shocks to correct an improperly beating heart and prevent sudden death from heart failure.

For the new study, the researchers tested a light defibrillator system on beating mouse hearts genetically altered to express proteins that react to light. They found a light pulse of one second restored normal rhythm to the rodent's hearts.

Advertisement

To test the system in humans, the researchers used a computer model based on MRI scans of a patient who had a heart attack and was at increased risk for arrhythmia as a result.

Though they had to use red light to penetrate human heart tissue -- blue light is effective in mouse hearts, which are smaller -- the model suggests an arrhythmia in the human heart could be corrected.

The researchers note cardiac optogenetics is a new technology and much more research is needed, though modeling similar to that done in the new study will play a key role in its development.

"The new method is still in the stage of basic research," Philipp Sasse, a junior professor at the University of Bonn, said in a press release. "Until implantable optical defibrillators can be developed for the treatment of patients, it will still take at least five to 10 years."

Latest Headlines