Wiring the Brain to Treat Central Sleep Apnea

A new strategy to treat central sleep apnea suggests implanting a device that acts like a pacemaker for the brain.

Over one-third of patients recovering from heart failure must then live with central sleep apnea, a frightening disorder where a patient’s brain sometimes fails to send the body the signal to breathe. Implanting a small device similar to a pacemaker, however, seems to work effectively to reset the brain so that it receives a constant reminder to send the “breathe” signal during sleep.

Researchers from Ohio State University Wexner Medical Center noted their concern that there is no easy treatment for central sleep apnea, which at worst case can be deadly, but can otherwise cause continued interrupted sleep and disturbed sleep patterns.

“The patient is aroused while this is happening, which places a lot of stress on the heart and vascular system,” said study author William Abraham, MD, director of the Division of Cardiovascular Medicince at the Wexner Medical Center.

Central sleep apnea differs from the more widespread form of common obstructive sleep apnea — while central sleep apnea is the result of one’s brain not sending a signal to breathe, obstructive sleep apnea results by a collapse in the upper airway that prevents air from reaching the lungs, often the result of obesity.

The same machines that help promote healthy breathing for people with obstructive sleep apnea don’t help those with central sleep apnea, so researchers turned to find another method.

What these patients needed was a way to ensure that a signal needed regularly wasn’t interrupted, and to do that, the researchers had the idea of mimicking a pacemaker for a heart, but for the brain.

This is not only similar to a pacemaker, but it a similar concept has been used for managing epilepsy and in assisting infants who are born without the drive to breathe, all of which have been largely successful, said Sanjeev Kothare, MD, associate professor of Pediatric Neurology and director of pediatric sleep medicine at NYU Langone Medical Center. “I think it’s very promising,” he said.

With Respicardia Inc, the researchers developed a device that could be implanted below the collar bone with a wire connecting it to the phrenic nerve, which carries the brain’s signal to breathe to the diaphragm. The device would send a consistent signal to the nerve, thus generating more consistent breath.

The researchers then implanted the device in 47 different patients with the condition, including Leslie McGuire, seen above with his wife. Researchers at 11 clinics in the United States and Europe then monitored how they slept for the next six months.

Of all the patients with the new device, 76 percent reported that the device improved their quality of sleep. Only one patient reported feeling slightly worse, and the others were unchanged. The researchers found a marked improvement to sleep disturbances for the patients, as a majority of patients improved their sleep efficiency and percentage of rapid eye movement (REM) sleep. Additionally, the devices brought an 80 percent reduction in central sleep apnea events.

The participants also reported feeling less sleepy and being more alert, Abraham noted.

“They work well because you don’t have to do anything,” said Dr. Kothare, referencing that once the device has been implanted, the individual has no other responsibilities.

The research, which was presented today at the Heart Failure Society of America’s Annual Scientific Meeting, has not been published yet, but already the researchers are setting up a randomized control trial to test the success of the device against a control group.

By Susan E. Matthews