Aneurysm of the descending thoracic aorta, without rupture

This code identifies a localized, permanent dilation of the descending segment of the thoracic aorta, specifically when there is no evidence of a tear or breach in the vessel wall. This condition often results from weakening of the aortic wall, leading to an outward bulging.

Apply this code when documentation clearly states an aneurysm of the descending thoracic aorta and explicitly confirms the absence of rupture. This is typically diagnosed via imaging studies such as CT, MRI, or echocardiography. Use for surveillance, management, or workup of an unruptured descending thoracic aortic aneurysm.

• Differentiate carefully from ruptured descending thoracic aortic aneurysm (I71.21) or dissecting aneurysm (I71.02).
• Ensure the documentation specifies "descending thoracic" to avoid confusion with ascending or thoracoabdominal aneurysms.
• Always review imaging reports and physician notes for explicit statements regarding rupture status.