ICD-10 Code I71.13 – Aneurysm of the descending thoracic aorta, ruptured (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I71.13 – Aneurysm of the descending thoracic aorta, ruptured
What it is
This code identifies a ruptured aneurysm involving the descending thoracic aorta. It means the weakened aortic wall has expanded and then torn, creating a life-threatening emergency.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include sudden severe chest or back pain, shock, or evidence of internal bleeding, but the rupture must be documented or clearly supported by imaging or operative notes.
When to use this code
Use I71.13 when the record clearly states a ruptured aneurysm of the descending thoracic aorta. It may appear in emergency, inpatient, or operative documentation after imaging, surgical findings, or clinician assessment confirms rupture. Code only the documented site and rupture status.
Do not use for
Do not use this code for an unruptured thoracic aortic aneurysm or for aneurysms in other aortic segments. If the documentation is unclear about rupture or location, check documentation before assigning the code.
Coding tip
Verify both rupture and the descending thoracic aorta location in the same source note before coding.