I71.21 Aneurysm of the ascending aorta, without rupture

Billable ICD-10-CM code, FY2026.

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 V22: HCC 108 — Vascular Disease
• ESRD V24: HCC 108

MS-DRG index

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

Code annotations containing back-references to I71.21

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 I71.21

• Aneurysm (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular) › aorta, aortic (nonsyphilitic) › ascending
• Aneurysm (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular) › aorta, aortic (nonsyphilitic) › thorax, thoracic › ascending

Nearby codes

• 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
• I71.2 Thoracic aortic aneurysm, without rupture
• I71.20 Thoracic aortic aneurysm, without rupture, unspecified
• I71.21 Aneurysm of the ascending aorta, without rupture (this code)
• I71.22 Aneurysm of the aortic arch, without rupture
• I71.23 Aneurysm of the descending thoracic aorta, without rupture
• I71.3 Abdominal aortic aneurysm, ruptured
• I71.30 Abdominal aortic aneurysm, ruptured, unspecified
• I71.31 Pararenal abdominal aortic aneurysm, ruptured