Aneurysm of the descending thoracic aorta, ruptured

This code signifies a life-threatening condition where the main artery carrying blood from the heart to the lower body has a weakened, bulging wall that has torn open. This rupture leads to severe internal bleeding and is a medical emergency requiring immediate intervention.

Apply this code when documentation clearly states a ruptured aneurysm specifically located in the descending portion of the thoracic aorta. This diagnosis is typically made via imaging studies such as CT angiography and confirmed during surgical exploration or autopsy.

• Ensure the documentation specifies "descending thoracic" and "ruptured" to differentiate from other aortic segments or unruptured aneurysms.
• Always sequence this code as the principal diagnosis when it is the primary reason for the encounter, given its acute and severe nature.
• Do not confuse with I71.2 (thoracoabdominal aneurysm) or I71.11 (ascending aorta, ruptured) – anatomical specificity is crucial.