US researchers eye light beams to treat irregular heartbeats

Gentle light beams may soon replace electric shocks in treating arrhythmia or irregular heartbeats, if research by biomedical engineers out of John Hopkins and Stony Brook proves successful.

The potential new treatment promises a welcome change from electric jolts, which can cause pain and damage tissue, Johns Hopkins University said.

“Applying electricity to the heart has its drawbacks. When we use a defibrillator, it’s like blasting open a door because we don’t have the key. It applies too much force and too little finesse. We want to control this treatment in a more intelligent way. We think it’s possible to use light to reshape the behavior of the heart without blasting it,” said project supervisor Natalia Trayanova, the Murray B. Sachs Professor of Biomedical Engineering at Johns Hopkins.

JHU added the researchers believe this technique "could happen within a decade."

“One of the great things about using light is that it can be directed at very specific areas. It also involves very little energy. In many cases, it’s less harmful and more efficient than electricity,” said Patrick Boyle, a postdoctoral fellow in Trayanova’s lab and lead author of the Nature Communications paper.

Presently, other scientists are using light-sensitive cells to control certain activities in the brain.

But the Johns Hopkins-Stony Brook researchers plan to give this technique a "cardiac twist" to let doctors use low-energy light to solve serious heart problems like arrhythmia.

The study by the five biomedical engineers from Johns Hopkins and Stony Brook universities was published Aug. 28 in the online journal Nature Communications.

In the paper, they plan to use biological lab data and a computer model to devise a better way to heal ailing hearts.

Optogenetics

Trayanova’s team will dabble in optogenetics, which involves the insertion of light-responsive proteins called opsins into cells.

Such proteins when exposed to light will allow a stream of electrically charged ions to pass through.

So far, the researchers said they successfully tested this technique on a virtual, highly detailed computer model of a heart.

For their part, the researchers from Stony Brook are working on making the heart tissue light-sensitive by inserting opsins into some cells.

“Experiments from this lab generated the data we used to build our computer model for this project. As the Stony Brook lab generates new data, we will use it to refine our model,” Trayanova said.

Meanwhile, Trayanova’s team members will use the model to conduct virtual experiments to "position and control the light-sensitive cells."

"The overall goal is to use the computer model to push the research closer to the day when doctors can begin treating their heart patients with gentle light beams," the university said.

Once the technology is perfected, it could be integrated into light-based pacemakers and defibrillators.

"It is interesting to note that it was a Johns Hopkins electrical engineering researcher, William B. Kouwenhoven, who developed the closed-chest electric cardiac defibrillator, which has been used since was the 1950s to save lives," the university said. — LBG, GMA News