LM HCPCS Level II modifier: Left main coronary artery
LM is a HCPCS Level II modifier: “Left main coronary artery.” It adds this detail to the code it is reported with.
Official description
LMLeft main coronary artery
HCPCS · United States
Medicare details
The indicators CMS publishes with LM in its October 2026 file. They describe Medicare’s handling, not another payer’s.
- Medicare coverage
- Carrier judgment
- Added
- Jan 1, 2013
Where LM sits
- 1GroupHCPCS modifiers
- 2Modifier LMLeft main coronary artery
Source and release
- Data release
- HCPCS Level II · October 2026
- Effective date
- Oct 1, 2026
- Publisher
- CMS
This page is built from the HCPCS Level II catalog that Vero Codes reads when it suggests codes: Centers for Medicare & Medicaid Services’s October 2026 release, imported from the publisher’s file and checked against it. The description, notes and structured data come from the same record.
Frequently asked questions
What does HCPCS code LM mean?
LM is the HCPCS code for “Left main coronary artery” in CMS’s HCPCS Level II October 2026 release.
Where is LM in the HCPCS Level II list?
LM is listed under Modifiers.
Does Medicare cover LM?
CMS lists LM’s Medicare coverage as “Carrier judgment”. Coverage and payment still depend on the patient, the setting, the documentation and the payer.
Which HCPCS Level II release does this page use?
It uses CMS’s October 2026 release, in effect from Oct 1, 2026 to Dec 31, 2026. It is a reference: confirm the code against the current list and the payer’s rules before you submit it.
Codes beside LM
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