Dissection of unspecified artery

This code represents a tear in the inner lining of an arterial wall, allowing blood to flow between the layers and separate them. This can lead to an aneurysm, occlusion, or rupture, affecting blood flow to downstream tissues. The "unspecified artery" indicates that the specific vessel involved is not documented.

Assign this code when documentation clearly states an arterial dissection but does not specify the affected artery (e.g., "arterial dissection noted"). This is often used in initial reports or when the precise location is not yet determined or is not clinically relevant for the current encounter. Avoid using this code if a more specific anatomical site is known.

• Do not use this code if the specific artery (e.g., carotid, vertebral, renal) is identified; instead, use the more precise I77.7x codes.
• Always query the provider for clarification if the artery is not specified, as a more specific code often exists.
• Consider sequencing this code as a primary diagnosis when the dissection is the reason for the encounter, or as a secondary diagnosis if it's a co-morbidity.