CPT 93459 covers a left heart catheterization performed with both coronary angiography and bypass graft angiography. It exists so that post-CABG studies are reported as one code, and the errors around it come from practices that never switch away from 93458.
What CPT 93459 covers
93459 is catheter placement for coronary angiography, including intraprocedural injections, imaging supervision and interpretation, with left heart catheterization including injection(s) for left ventriculography when performed, and bypass graft angiography.
The graft imaging is the distinguishing element. In a patient with prior CABG whose grafts were selectively engaged and imaged, 93459 replaces 93458 entirely rather than being added to it.
Where 93459 sits in the cath family
93459 is coronary and bypass graft angiography with left heart catheterization. Without the grafts the session is 93458; add right heart catheterization and it becomes 93461. Graft angiography without any heart catheterization is 93455. See the complete 93451 to 93461 code map on the CPT 93458 guide.
Reimbursement context
93459 splits into professional and technical components, and the setting decides which you may report.
2026 Medicare RVUs for CPT 93459
| CPT 93459: 2026 Medicare RVUs (national, before GPCI) | ||||||
|---|---|---|---|---|---|---|
| Line | Work | PE, non-facility | PE, facility | Malpractice | Total, non-facility | Total, facility |
| Global (no modifier) | 6.19 | 25.08 | NA | 1.29 | 32.56 | NA |
| Professional (modifier 26) | 6.19 | 2.34 | 2.34 | 1.23 | 9.76 | 9.76 |
| Technical (modifier TC) | 0.00 | 22.74 | NA | 0.06 | 22.80 | NA |
Source: CMS CY 2026 PFS Relative Value File, RVU26D (October release, published 08/26/2026). RVUs are national and unadjusted; commercial payers set their own rates.
In the 2026 CMS relative value file, CPT 93459 carries 6.19 work RVUs and 32.56 total RVUs when billed globally in a non-facility setting. The global line is NA in a facility, because there the physician bills the professional component only and the facility bills the technical side. Its PC/TC indicator is 1: the code splits into a professional component (modifier 26, 9.76 total RVUs) and a technical component (modifier TC, 22.80 total RVUs), and the global line is billed only when one entity does both. Its global period is 000: related work on the day of the procedure is included, with no postoperative days. Across the diagnostic catheterization family, work RVUs run from 2.41 (93451) to 7.65 (93461); 93459 sits at 6.19.
To turn RVUs into payment, each component is multiplied by your locality's geographic practice cost index, the three are added, and the sum is multiplied by the 2026 conversion factor: $33.4009, or $33.5675 for qualifying APM participants (CMS-1832-F; CMS fact sheet). The CMS Physician Fee Schedule Look-Up Tool runs that calculation for your locality.
Documentation requirements
- The cardiac indication that justified the study, coded specifically.
- Access site, sheath and each catheter used.
- Every vessel or chamber selectively engaged, with findings.
- Hemodynamic measurements obtained, including pressures, gradients and saturations where applicable.
- Contrast volume and fluoroscopy time.
- A signed interpretation naming the study actually performed.
- Where an intervention followed in the same session, why the diagnostic study was necessary and not already available.
Medicare contractor billing articles. Each Medicare Administrative Contractor publishes its own billing and coding articles for this service, and the covered diagnoses differ by jurisdiction. Active examples in the CMS Medicare Coverage Database, checked September 28, 2026: A52850 (Cardiac Catheterization and Coronary Angiography, Wellpoint Federal) and A56500 (Cardiac Catheterization and Coronary Angiography, CGS). Use the article from the contractor that processes your claims.
Common denials and the exact fix
93458 reported when grafts were imaged
The most common and most costly 93459 error. It under-reports a more complex study on every post-CABG case, and it usually persists because the claim pays.
Fix: audit post-CABG catheterizations against the codes billed. Where grafts were selectively engaged and imaged, the correct code is 93459.
CO-97: separate graft angiography line billed alongside 93458
There is no add-on that bolts graft imaging onto 93458.
Fix: recode the claim to 93459.
Right heart catheterization performed in the same session
93451 next to 93459 describes a combined study.
Fix: report 93461, the combined right and left study with graft angiography.
CO-236: access, closure and guidance billed separately
Included through the same access in the same session.
Fix: remove those lines.
Grafts documented only in passing
A note that mentions prior CABG without documenting which grafts were engaged and what was found will not support the higher code on review.
Fix: document each graft engaged, the injections performed and the findings per graft.
What is already inside these codes
- Vascular access and sheath placement through the same access.
- Fluoroscopic guidance and roadmapping.
- Closure devices.
- The intraprocedural injections for the angiography described by the code.
- Imaging supervision and interpretation.
Billing any of these separately on the professional claim produces a CO-236 unbundling denial. Hospitals may still report closure device placement with HCPCS G0269, but it is packaged into the procedure rather than paid separately.One add-on is separately reportable with 93459 when genuinely performed and documented: 93567 for supravalvular aortography. Pulmonary artery angiography, 93568, pairs only with codes that include a right heart catheterization, so it is not reported with 93459.
Modifier rules
- 26 / TC: 93459 splits by setting. In a hospital the physician bills modifier 26 and the facility reports the technical side; the global line is only for one entity furnishing both. A modifier that contradicts the place of service is the most common modifier denial on 93459.
- 59 / XE / XP / XS / XU: only for a genuinely distinct service in a separate session, site or encounter. 93459 already contains the coronary angiography (93454), the graft angiography (93455) and the left heart study (93452, 93458), so none of them is added with a modifier.
- 51: multiple procedures; most payers apply it automatically.
- 22: increased procedural services on 93459 is rare, needs a narrative and goes to manual review.
- LC, LD, RC, RI, LM: vessel modifiers belong on intervention codes, not on 93459.
NCCI bundling edits
- 93454 is a component of 93459. Never report it alongside.
- 93451 with 93459: resolves to 93461.
- 93458 and 93459 are mutually exclusive for one session.
- Access, closure, guidance and angiographic injections are included.
- 93567: separately reportable where genuinely performed. 93568: not reported with 93459, because it pairs only with codes that include right heart catheterization.
Frequently asked questions
When should I bill 93459 instead of 93458?
Can I add a graft angiography line to 93458?
What documentation supports the graft component?
Sources
American Medical Association, CPT 2026 Professional Edition.
Centers for Medicare & Medicaid Services, CY 2026 PFS Relative Value File RVU26D (October release): RVUs, PC/TC indicator and global period for CPT 93459.
Centers for Medicare & Medicaid Services, CY 2026 Physician Fee Schedule final rule, CMS-1832-F: conversion factors.
Centers for Medicare & Medicaid Services, National Correct Coding Initiative Policy Manual for Medicare Services and quarterly procedure-to-procedure edit tables.
Medicare Coverage Database billing and coding articles A52850, A56500.
CPT® is a registered trademark of the American Medical Association. Payer policy and NCCI edits change quarterly, so check your own contractor before submission. How we verify this guidance.
Related codes
- CPT 93458. Left heart cath with coronary angiography.
- CPT 93461. Right and left heart cath with coronary and graft angiography.
- CPT 93454. Coronary angiography, no heart catheterization.
Related reading
- Cardiology billing & RCM. How we scrub cardiology claims across diagnostics, cath lab, EP and remote monitoring.
- Cardiac cath billing: NCCI bundling and modifier 59. Where cath lab bundling edits bite, and when a distinct-service modifier is genuinely earned.
- TC/26 modifier errors in cardiology. The split-billing mistakes that cost diagnostic practices the most.
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