Dissection of aortic arch

This code signifies an acute tear in the inner lining of the aortic arch, allowing blood to flow between the layers of the aortic wall. This creates a false lumen, potentially leading to compromised blood flow to the head, neck, and upper extremities. It is a life-threatening cardiovascular emergency.

Apply this code when documentation clearly indicates an aortic dissection specifically involving the aortic arch. This diagnosis is typically confirmed by imaging studies such as CT angiography, MRI, or transesophageal echocardiography. The physician's notes should explicitly state "dissection of aortic arch" or similar definitive language.

• Differentiate from dissections involving other aortic segments (e.g., ascending, descending, thoracoabdominal) as specific codes exist for each.
• Ensure documentation specifies the location of the dissection within the aorta, as this impacts code selection.
• Consider sequencing this code as the primary diagnosis when it is the reason for the encounter and acute treatment.