ICD-10 Code I77.70 – Dissection of unspecified artery (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I77.70 – Dissection of unspecified artery
What it is
This code identifies a dissection in an artery when the specific vessel is not named in the record. It means blood has split the arterial wall layers, creating an abnormal channel.
Clinical signs
Clinical features vary; refer to documentation. Common findings may include sudden pain, reduced blood flow, or imaging evidence of an arterial wall tear.
When to use this code
Use I77.70 when the clinician documents an arterial dissection but does not specify the artery involved. It is also appropriate when imaging or operative notes confirm dissection without laterality or vessel detail. Check documentation if another code identifies the exact artery.
Do not use for
Do not use this code when the record names a specific artery dissection, since a more precise code may apply. Check documentation and avoid using it for aneurysm, occlusion, or nonspecific vascular pain alone.
Coding tip
Query for the exact artery and laterality whenever the note says “dissection” but provides limited detail.