I26.93 Subsegmental Pulmonary Embolism: V28 HCC 267; Segmental or NOS Is I26.99

If you searched I26.93, subsegmental PE ICD-10, or single subsegmental pulmonary embolism without acute cor pulmonale, here is the short answer. I26.93 (Single subsegmental thrombotic pulmonary embolism without acute cor pulmonale) is a billable code that maps to CMS-HCC V28 HCC 267 (Deep Vein Thrombosis and Pulmonary Embolism). The PY2026 V28 CSV on HCC Buddy main has the row `I2693,267.0,,,`, the V28 column of the CMS 2026 Final ICD-10-CM Mappings lists 267 for it, and the live card shows HCC 267.

The code also carries an inclusion term, "Subsegmental pulmonary embolism NOS," so a provider who writes "subsegmental PE" and nothing more lands here. Multiple subsegmental emboli go to I26.94, which maps to HCC 267 as well.

What trips coders up is not the map. It is the neighboring words. A clot described as "segmental" is not a subsegmental one. A note that says "right heart strain" is not "acute cor pulmonale." And a PE that is "chronic" or "old" no longer belongs in category I26 at all. Those three choices decide the code, and the code has to match what the provider wrote.

The I26 codes, descriptors, and Tabular notes are the same in the FY2026 and FY2027 files, and the FY2027 Tabular and Index addenda have no entries for them.

Desk table: pulmonary embolism codes

Cement embolism (I26.03, I26.95) and fat embolism (I26.04, I26.96) also map to HCC 267. I26, I26.0, and I26.9 are nonbillable headings, and the live cards say so. Pick a billable child code.

How the code is built

Category I26 is Pulmonary embolism. Under it, the fourth character asks one question, and the fifth character names the type of embolus.

• I26.0- With acute cor pulmonale. The provider has to document acute cor pulmonale. I26.09 lists "Acute cor pulmonale NOS" as an inclusion term.
• I26.9- Without acute cor pulmonale. This is the branch when the provider has not documented it.
• Fifth character, the type. Septic is 1 under I26.0- and 0 under I26.9-. Saddle is 2. Cement and fat embolism follow, and "other" closes each branch (I26.09 and I26.99). The subsegmental pair, I26.93 and I26.94, exists only in the without-cor-pulmonale branch.

In the Alphabetic Index under Embolism, the subterm pulmonary (acute) (artery) (vein) leads to I26.99, and its own subterms refine that: single subsegmental without acute cor pulmonale I26.93, multiple subsegmental without acute cor pulmonale I26.94, subsegmental NOS I26.93, saddle I26.92 (with acute cor pulmonale I26.02), septic I26.90 (with acute cor pulmonale I26.01), cement I26.95 (I26.03), fat I26.96 (I26.04), and with acute cor pulmonale I26.09. Two more subterms matter later in this guide: chronic goes to I27.82, and healed or old goes to Z86.711.

Subsegmental, segmental, and "PE NOS"

Many of the searches that land on the I26.93 card ask about "segmental" PE. The word is one letter and one syllable away from the code's title, so it is worth being plain about it.

• If the provider documents a subsegmental embolus and no acute cor pulmonale, the Index and the I26.93 inclusion term send you to I26.93 for one, or I26.94 for multiple. Both codes are without acute cor pulmonale. When the provider documents acute cor pulmonale, the Index has no subsegmental subterm for it, so Embolism, pulmonary, with acute cor pulmonale leads to I26.09.
• If the provider documents a segmental, lobar, or other embolus without naming a type from the Index, the Index has no segmental subterm. It follows Embolism, pulmonary to I26.99, or to I26.09 when the provider documents acute cor pulmonale. The I26.99 inclusion terms are "Acute pulmonary embolism NOS," "Other thrombotic pulmonary embolism without acute cor pulmonale," and "Pulmonary embolism NOS."
• If the note says only "PE" or "pulmonary embolism," that is I26.99.
• If the note says "subsegmental" and is silent on how many, the inclusion term "Subsegmental pulmonary embolism NOS" is under I26.93.

Do not move a segmental clot into I26.93 to be specific. All of these map to HCC 267, so the choice never changes the V28 category. It does change whether the claim says what the chart says.

With or without acute cor pulmonale

Code I26.0- only when the provider documents acute cor pulmonale. The Tabular puts "Acute cor pulmonale NOS" under I26.09, so a provider who writes that phrase has given you what you need. The other I26.0- codes pair the same embolus types (septic, saddle, cement, fat) with it.

Words that are not that phrase should prompt a question, not a code. A note that reads "right heart strain" or "RV dilation" does not say acute cor pulmonale. If the picture matters to the claim, ask the provider whether acute cor pulmonale is present. If the provider says no or does not answer, the without branch (I26.9-) is where the embolus goes.

Chronic cor pulmonale is a different place altogether. I27.81 Cor pulmonale (chronic) maps to HCC 226 (Heart Failure, Except End Stage and Acute), with the CSV row `I2781,226.0,,,`. It carries an Excludes1 note for acute cor pulmonale (I26.0-), so as a rule the two do not go together on the same claim. Section I.A.12.a gives one exception: "An exception to the Excludes1 definition is the circumstance when the two conditions are unrelated to each other. If it is not clear whether the two conditions involving an Excludes1 note are related or not, query the provider." A new PE alone does not show that acute and chronic cor pulmonale are unrelated, so report both only when the provider's documentation supports that, and ask when it is unclear. I27.81 also has a "code also" note for right heart failure (I50.81-), if applicable. Do not read an I27.81 row as a PE row. It is not.

Chronic, healed, and old

Category I26 has an Excludes2 note for chronic pulmonary embolism (I27.82) and one for personal history of pulmonary embolism (Z86.711). The Index matches: under Embolism, pulmonary, chronic goes to I27.82, and healed or old and personal history of go to Z86.711.

• I27.82 Chronic pulmonary embolism maps to HCC 267 (`I2782,267.0,,,`). It has a "use additional code, if applicable" note for associated long-term (current) use of anticoagulants (Z79.01), and an Excludes1 note for personal history of pulmonary embolism (Z86.711).
• Z86.711 Personal history of pulmonary embolism has no V28 HCC and no CSV row.

Because the I26 note is an Excludes2, a patient can have a current acute PE and a chronic PE on the same claim when the provider documents both. Section I.A.12.b says that "When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate." Both codes fall in HCC 267, so the second one does not add a second category.

The words "chronic," "healed," "old," and "history of" are the provider's to write. The Tabular does not define them, and neither do the Official Guidelines. When the note leaves the question open, ask.

Anticoagulants, and how long an acute code lasts

Z79.01 Long term (current) use of anticoagulants has no V28 HCC. Section I.C.21.c.3 says "Assign a code from Z79 if the patient is receiving a medication for an extended period as a prophylactic measure (such as for the prevention of deep vein thrombosis) or as treatment of a chronic condition (such as arthritis) or a disease requiring a lengthy course of treatment (such as cancer)." The code describes the drug. It does not prove that a clot is current.

You may see a time window for an acute PE on a plan's tip sheet. The Official Guidelines and the Tabular set no such window for I26. The provider's current documentation is what you follow: whether the embolism is being treated as current at this visit, or the provider has documented that it has resolved. Follow your own program's policy, and when the note and the plan do not line up, ask.

• If the provider documents a current PE and is managing it, the I26 code is supported. Add Z79.01 when the patient is on long-term anticoagulation.
• If the provider documents that the PE has resolved and treatment is finished, Z86.711 fits, and it does not map. Section I.C.21.c.4 says "Personal history codes explain a patient's past medical condition that no longer exists and is not receiving any treatment, but that has the potential for recurrence, and therefore may require continued monitoring."
• If the note says "history of PE" while the plan shows the patient still treated for a clot the provider calls present, the two do not line up. Ask whether the PE is current, chronic, or resolved.

The CSV rows behind the answer

Each of these codes has one row in the PY2026 V28 CSV, with no age or sex condition:

• `I2601,267.0,,,`
• `I2602,267.0,,,`
• `I2603,267.0,,,`
• `I2604,267.0,,,`
• `I2609,267.0,,,`
• `I2690,267.0,,,`
• `I2692,267.0,,,`
• `I2693,267.0,,,`
• `I2694,267.0,,,`
• `I2695,267.0,,,`
• `I2696,267.0,,,`
• `I2699,267.0,,,`
• `I2782,267.0,,,`

The columns are ICD10, CC, MCE_AGE_CONDITION, AGE_EDIT_CONDITION, and SEX_EDIT_CONDITION. There is no row for I26, I260, I269, Z86711, or Z7901. The neighbor `I2781,226.0,,,` maps to HCC 226.

The CMS 2026 Final ICD-10-CM Mappings agree on V28 category 267 for each of the codes in the first list. One detail to know if you open that file: the acute cor pulmonale codes (I26.01 through I26.09) each appear on two rows. The V28 column holds 267 on the first row and is blank on the second, where the other model columns differ. This post covers the CMS-HCC V28 result only.

Where HCC 267 sits

In the V28 hierarchy file, the row for HCC 267 is `HCC267,,,,,,`. It lists no lower category, and no other row lists HCC 267. So HCC 267 does not supersede another category, and no category supersedes it. HCC 226 (Heart Failure, Except End Stage and Acute) is a separate row with its own hierarchy line, and it has no connection to 267.

The PY2026 V28 relative factors list HCC 267 with a CNA reference of 0.294 and a COMMUNITY_ND value of 0.431. These are community segment values, not member totals, and the segment a member is scored in depends on that member's enrollment data.

The live HCC 267 hub lists 167 codes, and that count matches the CSV.

When DVT and PE are both on the note

Category I82 has an Excludes2 note for venous embolism and thrombosis of "pulmonary (I26.-)". With Section I.A.12.b, that means a documented deep vein thrombosis and a documented pulmonary embolism can both go on the claim. The PE code maps to HCC 267, and so does a DVT code that has a V28 row. For example, I82.409 (Acute embolism and thrombosis of unspecified deep veins of unspecified lower extremity) has the row `I82409,267.0,,,`. Not every I82 code maps: I82.90 has no row. When both codes map, coding the second one does not change the category, so it comes down to whether each condition is documented and current.

Special types: septic, cement, fat, trauma, pregnancy

A few I26 codes carry notes you should read before you pick.

• Septic. I26.01 and I26.90 say to code first the underlying infection.
• Cement. I26.95 says to code first a complication of other artery following a procedure (T81.718).
• Fat. I26.96 says, if applicable, to code first a complication of other artery following a procedure (T81.718) or a traumatic fat embolism (T79.1).
• Excluded circumstances. The I26 Excludes2 notes name pulmonary embolism complicating abortion, ectopic or molar pregnancy (O00-O07, O08.2), complicating pregnancy, childbirth and the puerperium (O88.-), due to trauma (T79.0, T79.1), and due to complications of surgical and medical care (T80.0, T81.7-, T82.8-). Because these are Excludes2 notes, both codes can be reported when the documentation supports both.
• Cor pulmonale without embolism. I26 has an Excludes1 note for cor pulmonale without embolism (I27.81).

MEAT for a pulmonary embolism code

For I26.93 and the other I26 codes, the note should support the PE as a current condition the provider is managing, not just a line in the past history:

• M Monitor: how the provider is following the embolism at this visit
• E Evaluate: the imaging or other results the provider reviewed for it
• A Assess: the PE named as current, with the type (subsegmental, saddle, septic, other) and whether acute cor pulmonale is or is not present
• T Treat: the anticoagulation, referral, or other plan the provider documents for it

MEAT is a review mnemonic, not a universal CMS coding rule. Follow the applicable coding, encounter, program, and payer requirements. See MEAT.

Reporting rules that apply

Section IV.H says not to code diagnoses documented as "probable", "suspected," "questionable," "rule out," "compatible with," "consistent with," or "working diagnosis" or other similar terms indicating uncertainty, and to code "the condition(s) to the highest degree of certainty for that encounter/visit, such as symptoms, signs, abnormal test results, or other reason for the visit." The guideline notes that this differs from the practices of short-term, acute care, long-term care and psychiatric hospitals. A "rule out PE" or "possible subsegmental PE" in an office note is not coded as I26.93 or I26.99. Code what the provider has confirmed, or the symptoms and findings they document.

Audit and query traps

1. Moving a segmental or lobar clot into I26.93 because it sounds more specific. The Index has a subsegmental subterm and no segmental one; the note without a type is I26.99, or I26.09 with documented acute cor pulmonale.

2. Coding I26.0- from "right heart strain" without the provider documenting acute cor pulmonale.

3. Coding I27.81 (chronic cor pulmonale, HCC 226) as if it were a PE code.

4. Reporting I27.81 and I26.0- together without documentation that the two are unrelated. The Excludes1 note on I27.81 blocks that pair unless the Section I.A.12.a exception applies; query when the relationship is unclear.

5. Leaving a PE in I26 after the provider documents it as chronic. The Index sends chronic to I27.82, and the Excludes2 note on I26 lets both appear only when the provider documents both an acute and a chronic PE.

6. Carrying an acute I26 code forward after the provider documents the PE as resolved and treatment as finished. That is Z86.711, which does not map.

7. Treating Z79.01 as if it proves a current clot. It describes the drug, and it has no V28 HCC.

8. Dropping the I26 code because a DVT is also coded. The I82 Excludes2 lets both go on the claim. The PE code maps to HCC 267 even when the DVT code has no V28 row.

9. Skipping the code-first instruction on septic, cement, and fat embolism codes.

10. Using a CNA reference as a member RAF total, or inventing Coding Clinic quotes, competitor comparisons, or PHI examples.

Two-minute check

1. Does the provider document a pulmonary embolism as current, chronic, or resolved?

2. If current: with or without acute cor pulmonale, in the provider's own words?

3. What type does the provider name: subsegmental (single or multiple), saddle, septic, cement, fat, or none?

4. If none or only "segmental": I26.99 without acute cor pulmonale, or I26.09 with it documented. Not I26.93. If subsegmental: I26.93 or I26.94 only without acute cor pulmonale; with it documented, I26.09.

5. Is it chronic (I27.82) or healed, old, or history of (Z86.711)?

6. Add Z79.01 when the patient is on long-term anticoagulation. Read any code-first note on septic, cement, or fat embolism.

7. Expect HCC 267 for every I26 leaf code and I27.82 here, HCC 226 for I27.81, and no V28 HCC for Z86.711 and Z79.01.

8. Confirm the map on the live card and the CSV row. Confirm MEAT for this year.

Related desks and tools

• Live cards: I26.93, I26.94, I26.99, I26.09, I26.92, I27.82, I27.81, Z86.711, Z79.01
• Hubs: HCC 267
• Lookup: ICD-10 to HCC, Encoder
• Evidence habits: MEAT, provider query templates, acute vs history of, hierarchy and trumping rules
• Nearby: excludes 1 vs excludes 2, codes that do not map, status Z codes that map, FY2027 code changes

Sources

• Live HCC Buddy ICD-10-CM cards (FY2027 Tabular display) and the V28 HCC 267 hub, fetched November 9, 2026
• FY2026 and FY2027 ICD-10-CM order file billable flags, the FY2026 and FY2027 Tabular, the FY2027 Alphabetic Index, and the FY2027 Tabular and Index addenda
• CMS, FY2027 ICD-10-CM Official Guidelines for Coding and Reporting, Sections I.A.12.b, I.C.21.c.3, I.C.21.c.4, and IV.H
• PY2026 V28 mapping, hierarchy, and relative factor files on HCC Buddy main
• CMS, ICD-10 codes (FY2027 ICD-10-CM code files and addendum, effective October 1, 2026)
• CMS, 2026 Model Software/ICD-10 Mappings (PY2026 V28 mappings, hierarchies, relative factors, and the 2026 Final ICD-10-CM Mappings)

V28 mappings come from the cited live code pages and the PY2026 V28 CSV. Coefficients are source-labeled references, not member totals. Not medical advice. Not a Coding Clinic reprint.

Current as of November 9, 2026. Always confirm the V28 mapping for the payment year you are scoring and the live code card before you lock a map claim. The map claims here come from the PY2026 V28 CSV. For PY2027 scores, use the PY2027 V28 mapping.