Phrenic Nerve Stimulation Shows Benefits in Central Sleep Apnea With Heart Failure

— Use of the nerve stimulator tied to a fivefold higher chance of better clinical outcomes

MedicalToday

HOUSTON -- Use of transvenous phrenic nerve stimulation (TPNS) was linked to a five-fold higher chance of better clinical outcomes for patients with central sleep apnea and heart failure, according to a win ratio analysis of the Remedē system pivotal trial.

With a total of 1,141 (55.28%) winning pairwise comparisons for the treatment group and 222 (10.76%) for the control group, the win ratio for death, heart failure hospitalization, and a 25% improvement in 4% of the Oxygen Desaturation Index was 5.14 (95% CI 2.34-11.27, P<0.0001), reported Robin Germany, MD, of the University of Oklahoma College of Medicine in Oklahoma City, at the annual SLEEP meeting, hosted jointly by the American Academy of Sleep Medicine and the Sleep Research Society.

Germany told that these findings add to "an increasing amount of data that the treatment of central sleep apnea leads to clinical benefits. There's increasing evidence that the benefit outweighs the risks of the device," which included impending pocket erosion, hematoma, infection, component failure, lead dislodgement, lead displacement, non-cardiac chest pain, and elevated transaminase levels in the .

Based on the results from the pivotal trial, the FDA approved the Remedē device for moderate-to-severe central sleep apnea in 2017. Five-year data presented at the 2020 Heart Failure Society of America meeting supported the long-term safety and effectiveness of the device.

Compared with obstructive sleep apnea, central sleep apnea is characterized by an interruption in the process of sending signals from the respiratory control center of the brain to the body. This interruption causes muscles to cease activity, leading to an inability to maintain adequate breathing while sleeping.

While less common in the general population, central sleep apnea is frequently observed in patients with heart failure, affecting an estimated with congestive heart failure.

"Heart failure patients oftentimes start out where they are on a lot of different medications. They struggle because they are oftentimes short of breath to begin with -- even resting, they can be short of breath," said Germany. "And, so, sometimes they're not willing to try traditional sleep apnea therapies. So that makes this difficult."

The Remedē is a small implantable device that regularly stimulates a phrenic nerve to induce diaphragmatic contraction, creating negative intrathoracic pressure similar to normal breathing. The implant is placed below the collar bone, with a transvenous stimulator lead extending to the target nerve. The system starts automatically when the user is sleeping.

Germany noted that the device is implanted directly by a cardiologist under conscious sedation, rather than by an otolaryngologist, setting it apart from procedures for other stimulation devices for sleep apnea.

This retrospective win ratio analysis included patients with heart failure from the original pivotal trial. There were 43 participants in the treatment group, who had an active implanted device, and 48 in the control group, who had an inactive device. Participants provided 2,064 pairwise comparisons for three pre-defined components: longest survival, lowest heart failure hospitalization rates through 6 months, and 25% improvement in 4% Oxygen Desaturation Index.

In order to be included in the initial trial, patients needed to be considered medically stable 30 days prior to baseline assessments.

Of the patients in the TPNS group, median age was 67, and 91% were men. Median left ventricular ejection fraction (LVEF) was 34%. In the control group, median age was 69, 92% were men, and median LVEF was 33%.

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    Elizabeth Short is a staff writer for . She often covers pulmonology and allergy & immunology.

Disclosures

The study was sponsored by Zoll Respicardia.

Germany reported employment with Zoll Respicardia.

Primary Source

SLEEP

Khayat R, et al "Transvenous phrenic nerve stimulation to treat central sleep apnea in heart failure: win ratio analysis" SLEEP 2024; Abstract LBA 1321.