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MS-DRG 234 · MDC 05 · Surgical

MS-DRG 234: Coronary Bypass with Cardiac Catheterization or Open Ablation without MCC

Reviewed by QuickIntell RCM Editorial Team · Last reviewed

Data effective
Data currency: IPPS Table 5 FY2027 final rule (effective October 1, 2026); Definitions Manual v44 (effective October 1, 2026). Next CMS release: April 1, 2027 (v44.1 mid-year update), then the FY2028 final rule in August 2027.

Key facts for DRG 234

FY2027 relative weight
5.5040
Higher than 93% of all MS-DRGs
Change vs FY2026
+0.8%
FY2026 weight 5.4630
Geometric mean LOS
8.3 days
Arithmetic mean 8.8 days
MDC
05
Assignment of Diagnosis Codes
Severity level
without MCC
Transfer policy
Post-acute transfer DRG

TL;DR

MS-DRG 234 is a surgical group in MDC 05 (Assignment of Diagnosis Codes) at the base severity level of its family. CMS assigns it a FY2027 relative weight of 5.5040 with a geometric mean length of stay of 8.3 days and an arithmetic mean of 8.8. Its weight moved up 0.8% from FY2026 (5.4630). That weight is higher than 93% of all surgical and medical MS-DRGs. Its CC/MCC family (DRG 233) spans weights 5.5040 to 8.0160. The v44 Definitions Manual assigns it through 288 operating room procedures codes.

What changed from FY2026 to FY2027

CMS recalibrates every MS-DRG weight annually from the prior year's MedPAR claims. For DRG 234 the FY2027 relative weight is 5.5040 against 5.4630 in FY2026, a rise of 0.75%.

FY2026 versus FY2027 payment factors for MS-DRG 234
MetricFY2026FY2027Change
Relative weight5.46305.5040+0.0410
Geometric mean LOS (days)8.28.3+0.1
Arithmetic mean LOS (days)8.88.8+0.0
Weights shown are the FY2027 final values after the 10% cap on year-over-year reductions where applicable.

CC and MCC family

DRG 234 shares its base definition with 1 other MS-DRG split by severity. The family's weights span 5.5040 to 8.0160, a 1.46× spread, which is the payment effect of documenting qualifying complications and comorbidities.

MS-DRGs in the same base group as DRG 234
DRGTitleFY2027 weightGMLOS
233Coronary Bypass with Cardiac Catheterization or Open Ablation with MCC8.016011.2
234Coronary Bypass with Cardiac Catheterization or Open Ablation without MCC5.50408.3

Grouper logic (v44 Definitions Manual)

Operating Room Procedures: 288 ICD-10 codes drive assignment to this group; the first 12 are shown.

Operating Room Procedures codes assigned to DRG 234 (sample)
ICD-10 codeDescription
0210083Bypass Coronary Artery, One Artery from Coronary Artery with Zooplastic Tissue, Open Approach
0210088Bypass Coronary Artery, One Artery from Right Internal Mammary with Zooplastic Tissue, Open Approach
0210089Bypass Coronary Artery, One Artery from Left Internal Mammary with Zooplastic Tissue, Open Approach
021008CBypass Coronary Artery, One Artery from Thoracic Artery with Zooplastic Tissue, Open Approach
021008FBypass Coronary Artery, One Artery from Abdominal Artery with Zooplastic Tissue, Open Approach
021008WBypass Coronary Artery, One Artery from Aorta with Zooplastic Tissue, Open Approach
0210093Bypass Coronary Artery, One Artery from Coronary Artery with Autologous Venous Tissue, Open Approach
0210098Bypass Coronary Artery, One Artery from Right Internal Mammary with Autologous Venous Tissue, Open Approach
0210099Bypass Coronary Artery, One Artery from Left Internal Mammary with Autologous Venous Tissue, Open Approach
021009CBypass Coronary Artery, One Artery from Thoracic Artery with Autologous Venous Tissue, Open Approach
021009FBypass Coronary Artery, One Artery from Abdominal Artery with Autologous Venous Tissue, Open Approach
021009WBypass Coronary Artery, One Artery from Aorta with Autologous Venous Tissue, Open Approach

Documentation and denial exposure

As a surgical DRG, assignment depends on a qualifying operating-room procedure being coded from the operative report; a missing or non-OR procedure code drops the stay into a medical DRG in MDC 05 with a lower weight. Because this family splits by severity, auditors target CC and MCC capture: each secondary diagnosis must be documented as present, monitored, evaluated or treated during the stay to survive a DRG-validation review. Typical inpatient denial codes for this group: CARC 16 (claim lacks information needed to group the stay), CARC 50 (the admission or procedure is judged not medically necessary), CARC 97 (a service is bundled into the DRG payment).

How QuickIntell uses DRG 234 data

QuickCode groups inpatient encounters against the current v44 logic, flags CC and MCC candidates that lack supporting documentation, and shows the weight difference across the family before the claim drops. QuickScribe captures the attending's language that supports severity, and QuickRCM works DRG-validation denials with the grouper evidence attached.

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Frequently asked questions — DRG 234

What is MS-DRG 234?

MS-DRG 234 is "Coronary Bypass with Cardiac Catheterization or Open Ablation without MCC", a surgical Medicare Severity Diagnosis-Related Group in MDC 05, Assignment of Diagnosis Codes. Medicare pays inpatient stays grouped here at the hospital's base rate multiplied by the DRG relative weight.

What is the FY2027 relative weight for DRG 234?

The FY2027 relative weight is 5.5040 (IPPS final rule Table 5, effective October 1, 2026). In FY2026 it was 5.4630, a change of +0.8%.

What is the average length of stay for DRG 234?

CMS reports a geometric mean length of stay of 8.3 days and an arithmetic mean of 8.8 days for FY2027. The geometric mean is used for transfer-payment calculations.

Which DRGs are in the same CC/MCC family as 234?

DRG 233 (Coronary Bypass with Cardiac Catheterization or Open Ablation with MCC, weight 8.0160). The family's weights range from 5.5040 to 8.0160, so documented complications and comorbidities change payment materially.

What documentation supports the severity level of DRG 234?

DRG 234 is the base-severity assignment: no secondary diagnosis on the CC or MCC lists was coded, or the only ones present are excluded for this principal diagnosis. Revenue-integrity review here looks for undercapture, meaning conditions treated during the stay (electrolyte disorders, specified anemia, acute blood loss, pressure injuries present on admission) that were never documented to the specificity the lists require. A compliant query to the attending, not a coder assumption, is the only way to move a stay to the CC or MCC sibling.

Which codes group to DRG 234?

The v44 Definitions Manual lists 288 operating room procedures codes for this group. Examples from the operating room procedures list: 0210083 (Bypass Coronary Artery, One Artery from Coronary Artery with Zooplastic Tissue, Open Approach); 0210088 (Bypass Coronary Artery, One Artery from Right Internal Mammary with Zooplastic Tissue, Open Approach); 0210089 (Bypass Coronary Artery, One Artery from Left Internal Mammary with Zooplastic Tissue, Open Approach); 021008C (Bypass Coronary Artery, One Artery from Thoracic Artery with Zooplastic Tissue, Open Approach).

Is DRG 234 a post-acute transfer DRG?

Yes. CMS flags DRG 234 under the post-acute care transfer policy, so a discharge to a qualifying post-acute setting before the geometric mean length of stay is paid a per-diem amount rather than the full DRG payment.

Sources

Every figure on this page is taken from the CMS publications below, as released by the Centers for Medicare & Medicaid Services. Projection built 2026-10-01. Verify against the primary file before billing or contracting decisions.

Disclaimer

This page is an operational reference compiled from the CMS IPPS FY2027 final rule (Table 5) and the v44 ICD-10 MS-DRG Definitions Manual. Relative weights are national factors; actual payment depends on each hospital's wage-adjusted base rate, add-ons, outliers and transfer adjustments. Nothing here is legal, clinical or billing advice; verify grouping against your encoder and the published CMS files.