I71.00 Dissection of unspecified site of aorta

Billable ICD-10-CM code, FY2026. Acts as a Major Complication or Comorbidity (MCC) as a secondary diagnosis.

Applies from I71 Aortic aneurysm and dissection

Code first

• , if applicable:
• syphilitic aortic aneurysm (A52.01)
• traumatic aortic aneurysm (S25.09, S35.09)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 264 — Vascular Disease with Complications
• CMS-HCC V22: HCC 107 — Vascular Disease with Complications
• ESRD V24: HCC 107

MS-DRG index

Defines the logic of DRG(s) 299-301 in MDC 05.

Approximate ICD-9-CM (GEMs)

• 441.00 Dissection of aorta, unspecified site

Code annotations containing back-references to I71.00

Back-references to I71.0

• Use Additional: I16.1 Hypertensive emergency ("aortic dissection (I71.0-)")
• Type 2 Excludes: I77.7 Other arterial dissection ("dissection of aorta (I71.0-)")

Back-references to I71

• Type 2 Excludes: I72 Other aneurysm ("aneurysm (of) aorta (I71.-)")
• Type 1 Excludes: I77.81 Aortic ectasia ("aortic aneurysm and dissection (I71.-)")

Diagnosis Index entries for I71.00

• Dissection › aorta
• Hematoma (traumatic) (skin surface intact) › aorta, dissecting

Nearby codes

• I71 Aortic aneurysm and dissection
• I71.0 Dissection of aorta
• I71.00 Dissection of unspecified site of aorta (this code)
• I71.01 Dissection of thoracic aorta
• I71.010 Dissection of ascending aorta
• I71.011 Dissection of aortic arch
• I71.012 Dissection of descending thoracic aorta
• I71.019 Dissection of thoracic aorta, unspecified