Using beams of light could be a better method that is less painful and less damaging to the heart muscle.

‘Light-based treatment will provide a safer and gentle remedy for patients at high risk of arrhythmia - irregular heartbeat that can cause sudden cardiac death within minutes.’

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.




This 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.
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.
“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,” said Natalia Trayanova, from Johns Hopkins University.
Researchers conducted tests on beating mouse hearts whose cells had been genetically engineered to express proteins that react to light and alter electrical activity within the organ.
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“This is a very important result,” said Tobias Bruegmann, from University of Bonn. “It shows for the first time experimentally that light can be used for defibrillation of cardiac arrhythmia,” said Bruegmann.
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“Our simulations show that a light pulse to the heart could stop the cardiac arrhythmia in this patient,” said Patrick M Boyle, a Johns Hopkins research professor.
To penetrate human heart tissue, researchers used red light to stimulate the heart cells, instead of the blue light used in mice.
Boyle explained that the blue light used in the much smaller mouse hearts was not powerful enough to fully penetrate human heart tissue. The red light, which has a longer wavelength, was more effective in the virtual human tests.
“In addition to demonstrating the feasibility of optogenetic defibrillation in a virtual heart of a patient, the simulations revealed the precise ways in which light alters the collective electrical behavior of the cells in the heart to achieve the desired arrhythmia termination,” Trayanova said.
The study appears in the Journal of Clinical Investigation.
Source-Medindia