ICD-10 Code I77.810 – Thoracic aortic ectasia (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I77.810 – Thoracic aortic ectasia
What it is
Thoracic aortic ectasia means the thoracic aorta is mildly enlarged or dilated. It describes a widened aorta in the chest without necessarily implying an aneurysm.
Clinical signs
Clinical features vary; refer to documentation. Imaging may describe a mildly enlarged thoracic aorta, often found incidentally on CT, MRI, echocardiography, or chest imaging.
When to use this code
Use I77.810 when the provider documents thoracic aortic ectasia or mild thoracic aortic dilatation. It also fits cases where imaging confirms ectasia and the clinician links that finding to the encounter.
Choose this code when the record does not support aneurysm, dissection, or another more specific aortic disorder. Check documentation if the report uses mixed terms or if the significance of the finding is unclear.
Do not use for
Do not use this code for thoracic aortic aneurysm, dissection, or traumatic aortic injury. If the documentation names a different aortic condition, code that diagnosis instead.
Coding tip
Code the exact wording in the report and confirm whether the finding is ectasia, aneurysm, or another aortic abnormality.