ICD-10 Code I71.03 – Dissection of thoracoabdominal aorta (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I71.03 – Dissection of thoracoabdominal aorta
What it is
I71.03 identifies a tear in the inner wall of the thoracoabdominal aorta, allowing blood to split the vessel wall. Use it for documented dissection involving the descending thoracic aorta extending into the abdominal aorta.
Clinical signs
Clinical features vary; refer to documentation. Typical findings include sudden chest, back, or abdominal pain, pulse differences, or ischemic complications. Imaging such as CT angiography is commonly used to confirm the diagnosis.
When to use this code
Use this code when the provider documents dissection of the thoracoabdominal aorta, including acute or chronic dissection affecting both thoracic and abdominal segments. It may also apply when imaging or operative reports clearly localize the dissection to this region. If the record only says “aortic dissection,” check documentation for the involved segment before coding.
Do not use for
Do not use I71.03 for isolated thoracic or abdominal aortic dissection without thoracoabdominal involvement. Check documentation if the record describes aneurysm, rupture, or aortic dissection in another segment.
Coding tip
Code the exact aortic segment documented; when location is unclear, query the provider before assigning I71.03.