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Researchers are looking into light therapy as a way to treat atrial fibrillation. Victor Dyomin/Getty Images
  • Researchers are reporting that light therapy known as optogenetics may be useful in treating atrial fibrillation (AFib).
  • They say the treatment quickly restored a regular heart rhythm to rats affected by AFib.
  • Experts say the findings are interesting, but they aren’t sure light therapy will replace the current treatments for AFib.

Optogenetics – using light to control cells – could treat atrial fibrillation, according to a study published today in the Journal of Internal Medicine.

In their research, scientists used optogenetics to modify targeted cells in rats to restore a regular rhythm to hearts affected by atrial fibrillation (AFib).

Based on the response, the researchers reported that the technique could fully penetrate the atrial wall in humans to treat the heart condition.

They said this approach would offer a shock-free option for treating AFib or irregular or rapid heart rate. Once a physician completed the treatment, the researchers said, the heart would return to its regular rhythm immediately.

“The idea of using genetics to force express cardiac ion channels and using a light source to terminate AFib is quite remarkable,” said Dr. Aseem Desai, FHRS, an electrophysiologist at Providence Mission Hospital and the co-director of Mission Heritage Heart Rhythm Specialists in California who was not involved in the study.

“This study is mainly about proof of concept, not clinical application currently,” Desai told Medical News Today. “The study has two claims: 1) optogenetic cardioversion of AFib is possible in rat atria that have undergone negative remodeling that would be typically seen in AFib patients, and 2) the irradiation levels required for AF termination in the rat model can also penetrate human atrial tissue outside the body (ex vivo).”

This light-based technology is a long way off from being used in mainstream medicine.

“It is exciting from a scientific standpoint and as a proof of concept, but it is hard to envision it in a medical setting,” said Dr. Chirag Barbhaiya, a cardiac electrophysiologist at NYU Langone Heart and an assistant professor in the Department of Medicine in the Leon H Charney Division of Cardiology at NYU Grossman School of Medicine in New York.

“I think the most interesting part is that you can modify heart cells. It does open the possibility of treating rhythm problems in a less invasive way,” Barbhaiya, who was not involved in the study, told Medical News Today.

Dr. Rigved Tadwalkar, a cardiologist at Providence Saint John’s Health Center in California who also was not involved in the study, agrees that the findings are exciting and hold some promise for future treatments.

“We are changing and modifying how cardiac cells operate via light,” Tadwalkar told Medical News Today.
“Suppose you have a room and want to put electricity in it, but it doesn’t have any plugs. The wiring you need to install is the genetic material to modify the room. This changes how the room operates. In our example, it changes how cardiac cells operate. Then, you can use light to generate cardiac current to modify the heart rate.”

“But this is still very much experimental,” he added. “There is still a lot of work to be done. We need clinical trials in humans, long-term clinical data, and comparisons to other therapies. If it works in humans, it could offer a safe and effective alternative that is easier on the patient and could be done outside the hospital.”

“The concept is fascinating, but at this point, it is still investigational,” Tadwalkar noted.

Untreated AFib can lead to chronic fatigue and increase the risk of developing congestive heart failure or stroke.

Doctors treat AFib based on the patient’s condition, underlying health conditions, and goals, such as maintaining your heart rate, restoring a normal heart rhythm, and preventing blood clots.

“There are two steps to treating AFib,” Barbhaiya said. “The first is to restore regular rhythm, but the second step is more difficult – maintaining the regular rhythm. This involves finding the underlying condition and fixing that.”

“This technology might be able to accomplish the first step, but if it can’t accomplish the second, I don’t think it is as valuable a tool as we would like it to be,” Barbhaiya said.

Typically, doctors will recommend making lifestyle changes to manage AFib, such as:

  • Lose weight if needed
  • Increase physical activity
  • Manage stress
  • Quitting smoking
  • Eating a heart-healthy diet

Many people with AFib take medications to control it.

According to the American Heart Association, some of the medicines prescribed include:

  • Antiplatelets to stop blood clots from forming by preventing clumping.
  • Anticoagulants to slow down or prevent clots from forming.
  • Beta-blockers to help slow the heart rate.
  • Calcium-channel blockers to potentially slow the heart rate and reduce the strength of the heart’s contraction, reducing blood pressure.
  • Sodium-channel blockers to reduce the heart rate by lowering its ability to conduct electricity.
  • Potassium-channel blockers reduce the electrical signals that cause AFib.

According to the National Institutes for Health, other treatments include:

  • Electrical cardioversion – restores the heart rhythm by using low-energy shocks to the heart
  • Catheter ablation – a surgery procedure to destroy tissue that is causing the arrhythmia
  • Pacemaker – typically used when AFib is diagnosed along with another arrhythmia
  • Maze procedure – a surgical procedure that creates scars to help restore the normal heart rhythm

“Because cardioversion is relatively easy to set up and do, I’m not sure if it will be replaced by treatments like this,” Desai said..

“Studies like these are useful because they are thought-provoking and one of the main ways we expand our current thinking of disease processes and novel therapies,” he added.