CMS Updates Coverage Policy for Phrenic Nerve Stimulator (NCD 244)

CMS has issued a modification to National Coverage Determination 244, governing Medicare coverage of implanted phrenic nerve stimulators. This update affects how billing and clinical teams document medical necessity for patients with respiratory insufficiency who may qualify for this device as an alternative to mechanical ventilation. If your practice serves pulmonology, neurology, spinal cord injury, or thoracic surgery patients, this policy belongs on your radar.

What Is a Phrenic Nerve Stimulator? CMS NCD 244 Explained

A phrenic nerve stimulator is an implantable device that delivers electrical stimulation to the phrenic nerve, causing rhythmic diaphragmatic contractions that produce breathing. CMS classifies this device under the Prosthetic Devices benefit category for Medicare billing purposes.

The device is designed as an alternative to two burdensome long-term therapies: intermittent or permanent mechanical ventilation and maintenance of a permanent tracheotomy stoma. For patients living with chronic respiratory failure, a functioning phrenic nerve stimulator can represent a meaningful improvement in quality of life and a reduction in the clinical infrastructure required to keep them breathing safely.

CMS recognizes the device's proven track record across several underlying conditions, including respiratory paralysis from brainstem or cervical spinal cord lesions and chronic pulmonary disease with ventilatory insufficiency. That breadth of applicable diagnoses makes this NCD relevant across multiple specialty lines.

CMS Coverage Criteria: Who Qualifies Under NCD 244?

The Centers for Medicare & Medicaid Services covers implantation of a phrenic nerve stimulator for selected patients with partial or complete respiratory insufficiency. That qualifying phrase—"selected patients"—is doing a lot of work here, and your clinical documentation needs to support it explicitly.

The Non-Negotiable Anatomical Requirement

Coverage under NCD 244 hinges on one critical anatomical condition: the patient must have an intact phrenic nerve and diaphragm. If the phrenic nerve or diaphragm is compromised, the device cannot function as intended, and the implantation will not meet Medicare's medical necessity standard.

This requirement has a direct billing implication. Pre-operative diagnostic workup confirming phrenic nerve and diaphragm integrity should be documented in the medical record before the implant procedure. Without that documentation, claims are highly vulnerable to denial or post-payment audit scrutiny.

Surgical Risk and the Device Failure Scenario

CMS explicitly acknowledges a clinically important reality in this policy: nerve injury can occur during the surgical implant procedure itself. If sufficient injury occurs, the device will fail to assist the patient, who may then return to mechanical ventilation.

This acknowledgment matters for billing teams because it establishes that a covered, medically necessary implantation may result in a clinically unsuccessful outcome—and that outcome alone does not retroactively make the initial claim non-covered. Documentation should clearly establish pre-operative eligibility regardless of post-operative device performance.

CMS Cross-Reference: Electrical Nerve Stimulation NCD 160

NCD 244 explicitly cross-references the CMS National Coverage Determination on Electrical Nerve Stimulation (NCD 160). Billing teams handling phrenic nerve stimulator claims should review NCD 160 for any overlapping guidance that could affect how CMS processes these claims.

This cross-reference is particularly relevant if your claims involve related neurostimulation procedures or if a payer contractor raises a coverage question that touches on broader electrical stimulation policy. Having both NCDs in your documentation file is a straightforward protective step.

Affected Codes

The current version of NCD 244 does not list specific CPT or HCPCS codes within the policy document itself. No ICD-10-CM diagnosis codes are enumerated in the policy data.

This is an important operational note for billing teams. The absence of enumerated codes in the NCD does not mean the procedure is uncodeable—it means your MAC (Medicare Administrative Contractor) or the applicable claims processing instructions govern code selection. You will need to work from your MAC's local coverage determinations (LCDs) or billing guidance to identify the correct procedure codes for the implantation and any associated services.

Consult your MAC's website and cross-reference the Claims Processing Instructions section linked from the CMS Medicare Coverage Database entry for NCD 244.

What Your Billing Team Should Do