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ICD-10-PCS 2027 procedure code

021W4ABBypass Thoracic Aorta, Descending to Subclavian with Autologous Arterial Tissue, Percutaneous Endoscopic Approach

✓ Valid for 2027O.R. procedure

Short description: Bypass Thor Aorta Desc to Subclav w Autol Art, Perc Endo

Code last changed in FY2017 (effective October 1, 2016). Source: official FY2027 ICD-10-PCS release from CMS. Page updated September 29, 2026. About our data

About 021W4AB

021W4AB is the ICD-10-PCS code for a bypass procedure on the thoracic aorta, descending using a percutaneous endoscopic approach with autologous arterial tissue (qualifier: subclavian). In ICD-10-PCS, bypass means altering the route of passage of the contents of a tubular body part.

In plain terms, this corresponds to Aorta-subclavian-carotid bypass, the ICD-9-CM procedure title it maps to (39.22).

For a different body part, codes include 021P4AB (pulmonary trunk), 021Q4AB (right pulmonary artery), 021R4AB (left pulmonary artery) and 021X4AB (thoracic aorta, ascending/arch).

The same procedure with a different approach is coded 021W0AB (open).

With a different device, use 021W48B (zooplastic tissue), 021W49B (autologous venous tissue), 021W4JB (synthetic substitute), 021W4KB (nonautologous tissue substitute) and 021W4ZB (no device).

It is an operating-room procedure in the MS-DRG logic for DRG 037 (Extracranial Procedures with MCC), DRG 038 (Extracranial Procedures with CC), DRG 039 (Extracranial Procedures without CC/MCC), DRG 270 (Other Major Cardiovascular Procedures with MCC), DRG 271 (Other Major Cardiovascular Procedures with CC) and DRG 272 (Other Major Cardiovascular Procedures without CC/MCC), under the surgical categories “Extracranial Procedures”, “Other Major Cardiovascular Procedures”, “Other O.R. Procedures for Injuries” and 1 more.

It has been valid since ICD-10-PCS took effect on October 1, 2015.

What each character means

1. Section
0Medical and Surgical
2. Body System
2Heart and Great Vessels
3. Operation
1Bypass

Altering the route of passage of the contents of a tubular body part

Rerouting contents of a body part to a downstream area of the normal route, to a similar route and body part, or to an abnormal route and dissimilar body part. Includes one or more anastomoses, with or without the use of a device

Includes: Coronary artery bypass, colostomy formation

4. Body Part
WThoracic Aorta, Descending
5. Approach
4Percutaneous Endoscopic

Entry, by puncture or minor incision, of instrumentation through the skin or mucous membrane and any other body layers necessary to reach and visualize the site of the procedure

6. Device
AAutologous Arterial Tissue
7. Qualifier
BSubclavian

Other versions of this procedure

Different approach

MS-DRG v44.0 grouping

All DRGs →

Surgical MS-DRGs this procedure can group to, depending on the principal diagnosis's MDC.

ICD-9-CM equivalent

Converter →
  • 39.22Aorta-subclavian-carotid bypassapproximate

From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.

Code history

  1. 2016
  2. 2017
  3. 2018
  4. 2019
  5. 2020
  6. 2021
  7. 2022
  8. 2023
  9. 2024
  10. 2025
  11. 2026
  12. 2027
  • FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
  • FY2017 (effective 10/1/2016): Title revised — was “Bypass Thoracic Aorta to Subclavian with Autologous Arterial Tissue, Percutaneous Endoscopic Approach”

Common questions about 021W4AB

Is 021W4AB a valid ICD-10-PCS code for 2027?

Yes. 021W4AB is valid for inpatient procedures from October 1, 2026 through September 30, 2027.

Is 021W4AB an O.R. procedure?

Yes. 021W4AB is an O.R. procedure in MS-DRG v44.0.

What DRG does 021W4AB group to?

Depending on the principal diagnosis, 021W4AB can group to MS-DRG 037, MS-DRG 038, MS-DRG 039, MS-DRG 270, MS-DRG 271 and MS-DRG 272.

What is the ICD-9 procedure code for 021W4AB?

The CMS GEMs map 021W4AB to ICD-9-CM 39.22 (Aorta-subclavian-carotid bypass).