Heat Treatment, Including the Use of Diathermy and Ultra-Sound for Pulmonary Conditions | CMS Coverage Update

Summary: The Centers for Medicare & Medicaid Services modified its coverage policy for heat treatment — including diathermy and ultrasound — for pulmonary conditions, with an effective date of May 15, 2026. Here's what billing teams need to know before claims start moving through the system.

CMS has long maintained a non-coverage position on heat treatment modalities for pulmonary conditions. This modification touches a policy that governs how Medicare reimburses — or more accurately, doesn't reimburse — procedures like diathermy and therapeutic ultrasound when applied to treat pulmonary disease. The policy does not list specific CPT or HCPCS codes in the data available at publication. If your billing team submits claims for these services in a pulmonary context, this policy change has direct financial exposure for your practice.

Quick-Reference Table

CMS Heat Treatment for Pulmonary Conditions Coverage Criteria and Medical Necessity Requirements 2026

The CMS heat treatment for pulmonary conditions coverage policy has historically been one of the clearer "no coverage" positions in Medicare's national policy library. CMS has generally found that heat treatment — whether delivered via diathermy or therapeutic ultrasound — lacks sufficient clinical evidence to support its use as a treatment for pulmonary conditions. That position drives claim denial at the MAC level before documentation even comes into play.

What makes this 2026 modification worth your attention is the signal it sends. When CMS revisits a longstanding non-coverage policy, it's either tightening the language to close billing gaps or responding to new evidence and coding patterns that have emerged in the field. Both scenarios require your billing team to act.

The Centers for Medicare & Medicaid Services governs this coverage policy at the national level, which means it applies uniformly across all Medicare Administrative Contractor jurisdictions. There's no regional carve-out here. If your MAC had previously issued a local coverage determination that touched on these modalities in a pulmonary context, check for alignment with the updated national policy — local policy cannot override a national coverage determination.

Medical necessity is the central issue. CMS uses medical necessity criteria to determine whether a service is "reasonable and necessary" under Section 1862(a)(1)(A) of the Social Security Act. For heat treatment modalities applied to pulmonary conditions, CMS has not found that standard met. The modification effective May 15, 2026, should be reviewed line by line to see if that position has shifted, narrowed, or been clarified with new language.

Prior authorization is not typically associated with these modalities under Medicare, because the denial happens at the coverage level rather than the authorization level. That said, if your practice has been billing these services under a different primary indication — musculoskeletal, for example — and the pulmonary condition appears as a secondary diagnosis, your claim exposure changes. Talk to your compliance officer before the May 15, 2026, effective date if that describes your billing pattern.

CMS Heat Treatment Exclusions and Non-Covered Indications

CMS's position on heat treatment for pulmonary conditions is grounded in a lack of clinical evidence, not a procedural or administrative exclusion. That's an important distinction. An administrative exclusion can sometimes be worked around with documentation. A non-coverage finding based on clinical evidence means the service is considered not reasonable and necessary — full stop.

Diathermy uses high-frequency electromagnetic energy to generate heat within tissue. Therapeutic ultrasound uses sound waves for the same purpose. Both have legitimate, covered uses in other clinical contexts — musculoskeletal rehabilitation, for example. The exclusion here is specific to pulmonary conditions as the primary indication.

If your team is billing heat treatment under a physical medicine indication for a patient who also has a pulmonary diagnosis, document carefully. CMS auditors look at the full clinical picture. If the record suggests the real intent was to treat the pulmonary condition, the claim is vulnerable regardless of how the codes are stacked.

Coverage Indications at a Glance

The policy data available at publication does not include a specific breakdown of covered versus non-covered indications with associated codes. The table below reflects what the policy title and CMS's known coverage position indicate. If the published policy document includes additional indication-level detail, update this table from the source at app.payerpolicy.org.

CMS Heat Treatment Billing Guidelines and Action Items 2026

The billing guidelines here are straightforward. This is a non-coverage policy, and the action items center on protecting your practice from unnecessary claim denials and potential audits.

CPT, HCPCS, and ICD-10 Codes for Heat Treatment Under This CMS Policy

The policy data available at publication does not list specific CPT, HCPCS Level II, or ICD-10-CM codes. This is not unusual for older CMS national policies that predate the current coding structure — the policy addresses the clinical service, and code applicability is interpreted from the clinical description.

What this means for your billing team: Do not assume the absence of listed codes means the policy doesn't apply to your claims. CMS reviewers and MAC auditors apply the coverage policy to claims based on the clinical service billed, not just a code-to-policy match.

The following code categories are clinically relevant to this policy based on the service descriptions. Confirm exact codes with your coding team and the full published policy document before the effective date of May 15, 2026.

Clinically Relevant Code Categories (Not Confirmed in Policy Data)

Do not bill based on this table alone. Pull the full policy text from app.payerpolicy.org/p/cms/4-v1 and confirm current CPT codes for these modalities with your coding staff or a certified coding consultant before May 15, 2026.

The absence of specific codes in the policy data is itself a risk signal. When CMS doesn't enumerate codes, the coverage policy applies by service type — and that gives auditors more discretion, not less. That's the real issue here.