I71.011 ICD-10-CM Code: Dissection of aortic arch

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for I71.011 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2027Effective: October 1, 2026

Notes without a marker are published on I71.011 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for I71.011

MedCoder structured workflow — derived from this code’s own official record

Choose the right path

1. Is the underlying (etiologic) condition the Code First note names documented?
   Yes → Sequence the underlying condition first, then I71.011.
   No → Continue; do not add an underlying condition the record does not document.

   ReviewA52.01, S25.09, S35.09

Consider I71.011. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement

Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).

The underlying (etiologic) condition

Named in the Code First note; sequenced before this code when documented (Guidelines I.A.13).

Official instructions as workflow

• Code First — sequencing check(3 notes)

  Coding workflow: Check whether the underlying or etiologic condition the note names is documented. When it is, sequence it before I71.011. Do not add an underlying condition the record does not document.

  ReviewA52.01, S25.09, S35.09

  See the official tabular notes · Guidelines I.A.13

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Indexed Clinical Terms (1)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

• Dissection, aorta, thoracic, aortic arch

Don’t confuse I71.011 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of I71.011 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

• I71.019— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Dissection of thoracic aorta, unspecified” takes I71.019; specificity in the record moves it back here.

  Full comparison: I71.011 vs I71.019 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Verify Before Coding

• MCC as a secondary diagnosis (FY2027). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name I71.011 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: I77.81 — Aortic ectasia (via I71.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 2 Excludes2 notes: I72 — Other aneurysm (via I71.-), I77.7 — Other arterial dissection (via I71.0.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

Referenced by 1 Code Also instruction: I16.1 — Hypertensive emergency (via I71.0.-).

These codes suggest coding this condition alongside when both are present.

MS-DRG Grouper Relationships (FY2027)

Potential MS-DRG participation — not a DRG assignment.

FY2027 MS-DRG: MCC — Major Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 54 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 3 MS-DRGs: DRG 299 (MDC 05), DRG 300 (MDC 05), DRG 301 (MDC 05).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):CIR027 — Arterial dissections (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as MCC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

E11.52 — Type 2 diabetes mellitus with diabetic peripheral angiopathy with gangrene, E11.59 — Type 2 diabetes mellitus with other circulatory complications, E13.51 — Other specified diabetes mellitus with diabetic peripheral angiopathy without gangrene, E13.52 — Other specified diabetes mellitus with diabetic peripheral angiopathy with gangrene, E13.59 — Other specified diabetes mellitus with other circulatory complications, I27.841 — Fontan-associated lymphatic dysfunction, I27.848 — Other Fontan-associated condition, I27.849 — Fontan related circulation, unspecified, I71.00 — Dissection of unspecified site of aorta, I71.010 — Dissection of ascending aorta, I71.012 — Dissection of descending thoracic aorta, I71.019 — Dissection of thoracic aorta, unspecified, I71.02 — Dissection of abdominal aorta, I71.03 — Dissection of thoracoabdominal aorta, I71.10 — Thoracic aortic aneurysm, ruptured, unspecified, I71.11 — Aneurysm of the ascending aorta, ruptured, I71.12 — Aneurysm of the aortic arch, ruptured, I71.13 — Aneurysm of the descending thoracic aorta, ruptured, I71.20 — Thoracic aortic aneurysm, without rupture, unspecified, I71.21 — Aneurysm of the ascending aorta, without rupture, +33 more

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Vascular Disease with Complications) for risk-adjusted payment.

I70.623 — Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, bilateral legs, I70.628 — Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, other extremity, I70.629 — Atherosclerosis of nonbiological bypass graft(s) of the extremities with rest pain, unspecified extremity, I70.721 — Atherosclerosis of other type of bypass graft(s) of the extremities with rest pain, right leg, I70.722 — Atherosclerosis of other type of bypass graft(s) of the extremities with rest pain, left leg, I70.723 — Atherosclerosis of other type of bypass graft(s) of the extremities with rest pain, bilateral legs, I70.728 — Atherosclerosis of other type of bypass graft(s) of the extremities with rest pain, other extremity, I70.729 — Atherosclerosis of other type of bypass graft(s) of the extremities with rest pain, unspecified extremity, I71.00 — Dissection of unspecified site of aorta, I71.010 — Dissection of ascending aorta, I71.012 — Dissection of descending thoracic aorta, I71.019 — Dissection of thoracic aorta, unspecified, I71.02 — Dissection of abdominal aorta, I71.03 — Dissection of thoracoabdominal aorta, I71.10 — Thoracic aortic aneurysm, ruptured, unspecified, I71.11 — Aneurysm of the ascending aorta, ruptured, I71.12 — Aneurysm of the aortic arch, ruptured, I71.13 — Aneurysm of the descending thoracic aorta, ruptured, I71.30 — Abdominal aortic aneurysm, ruptured, unspecified, I71.31 — Pararenal abdominal aortic aneurysm, ruptured, +50 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Atherosclerosis of Arteries of the Extremities with Ulceration or Gangrene

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Arterial dissections).

I25.42 — Coronary artery dissection, I67.0 — Dissection of cerebral arteries, nonruptured, I71.00 — Dissection of unspecified site of aorta, I71.01 — Dissection of thoracic aorta, I71.010 — Dissection of ascending aorta, I71.012 — Dissection of descending thoracic aorta, I71.019 — Dissection of thoracic aorta, unspecified, I71.02 — Dissection of abdominal aorta, I71.03 — Dissection of thoracoabdominal aorta, I77.70 — Dissection of unspecified artery, I77.71 — Dissection of carotid artery, I77.72 — Dissection of iliac artery, I77.73 — Dissection of renal artery, I77.74 — Dissection of vertebral artery, I77.75 — Dissection of other precerebral arteries, I77.76 — Dissection of artery of upper extremity, I77.77 — Dissection of artery of lower extremity, I77.79 — Dissection of other specified artery

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Dissection”; these codes share that main term but sit in a different category of the Tabular List.

I25.42 — Coronary artery dissection (artery, coronary), I67.0 — Dissection of cerebral arteries, nonruptured (artery, cerebral), I77.70 — Dissection of unspecified artery (artery), I77.71 — Dissection of carotid artery (artery, carotid), I77.72 — Dissection of iliac artery (artery, iliac), I77.73 — Dissection of renal artery (artery, renal), I77.74 — Dissection of vertebral artery (artery, vertebral), I77.75 — Dissection of other precerebral arteries (artery, basilar), I77.76 — Dissection of artery of upper extremity (artery, extremity, upper), I77.77 — Dissection of artery of lower extremity (artery, extremity, lower), I77.79 — Dissection of other specified artery (artery, specified NEC), I99.8 — Other disorder of circulatory system (vascular), Q28.1 — Other malformations of precerebral vessels (precerebral artery, congenital)

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Lipid Panel, Prothrombin Time Test and INR (PT/INR)

Contextual Map

Every relationship of I71.011 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run I71.011 with these 4 related codes in Claim Check

Hierarchy

• I00-I99 — Chapter 9: Diseases of the Circulatory System (I00-I99) (I00-I99)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I70-I79 — Diseases of arteries, arterioles and capillaries[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• I77.81 — Aortic ectasia[Excludes1](via I71.-): “aortic aneurysm and dissection (I71.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Excludes2 notes

• I72 — Other aneurysm[Excludes2](via I71.-): “aneurysm (of) aorta (I71.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026
• I77.7 — Other arterial dissection[Excludes2](via I71.0.-): “dissection of aorta (I71.0-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Referenced by Code Also instructions

• I16.1 — Hypertensive emergency[Code Also](via I71.0.-): “aortic dissection (I71.0-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• CIR027 — Arterial dissections[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

• HCC 264 — Vascular Disease with Complications [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

• MCC — Major Complication or Comorbidity [MS-DRG severity]: “As a secondary diagnosis this code can raise the stay's MS-DRG severity tier (MCC).”— CMS MS-DRG Definitions Manual (Appendix C) · FY2027
• DRG 299 — PERIPHERAL VASCULAR DISORDERS WITH MCC[MS-DRG]: “PERIPHERAL VASCULAR DISORDERS WITH MCC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
• DRG 300 — PERIPHERAL VASCULAR DISORDERS WITH CC[MS-DRG]: “PERIPHERAL VASCULAR DISORDERS WITH CC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027
• DRG 301 — PERIPHERAL VASCULAR DISORDERS WITHOUT CC/MCC[MS-DRG]: “PERIPHERAL VASCULAR DISORDERS WITHOUT CC/MCC (MDC 05)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2027

MDC crossing

• MDC 05 — Diseases and Disorders of the Circulatory System[MDC crossing]: “Diseases and Disorders of the Circulatory System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 15,708 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2027

Index entries

• Dissection, aorta, thoracic, aortic arch[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (39)

• I71 — Aortic aneurysm and dissection[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.0 — Dissection of aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.00 — Dissection of unspecified site of aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.01 — Dissection of thoracic aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.010 — Dissection of ascending aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.012 — Dissection of descending thoracic aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.019 — Dissection of thoracic aorta, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• I71.02 — Dissection of abdominal aorta[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• and 31 more

Change history

• FY2023 — Added to the code set[Change history]— CMS release files (code change ledger) · icd10cm-fy2023

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data

CMS/CDC ICD-10-CM FY2027 tabular list, index and tables, effective October 1, 2026 Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v44.0 (October 2026) Release, file and checksum · Publisher’s page

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v44 Release, file and checksum · Publisher’s page

Risk adjustment Official source data

2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page

Change history and date-of-service validity Official source data

CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page

Comparisons, relationships and the contextual map MedCoder structured relationship

Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears

Summary and FAQ answers MedCoder explanation

Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to I71.011 in its code family, with their registry titles.

• I71 — Aortic aneurysm and dissection
• I71.0 — Dissection of aorta
• I71.00 — Dissection of unspecified site of aorta
• I71.01 — Dissection of thoracic aorta
• I71.010 — Dissection of ascending aorta
• I71.012 — Dissection of descending thoracic aorta
• I71.019 — Dissection of thoracic aorta, unspecified
• I71.02 — Dissection of abdominal aorta
• I71.03 — Dissection of thoracoabdominal aorta
• I71.1 — Thoracic aortic aneurysm, ruptured

View all codes in the I71 family