Radiology Coding Alert

Aortic anatomy lesson helps keep your coding on the straight and narrow.

An important element of abdominal aortic aneurysm (AAA) coding is knowing whether the aneurysm has ruptured. Here’s a quick look at diagnosis coding for unruptured AAA, which is a ballooning of the portion of the aorta located in the abdomen.

ICD-9-CM Code

• 441.4, Abdominal aneurysm without rupture

ICD-10-CM Code

• I71.4, Abdominal aortic aneurysm, without rupture

ICD-9 coding rules: Code 441.4 is appropriate for an unruptured aneurysm of the abdominal aorta. ICD-9 provides separate codes for a ruptured aneurysm (441.3) and for aortic aneurysms in other locations (such as 441.2, Thoracic aneurysm without rupture).

ICD-10 changes: Your ICD-10 options are almost identical to your ICD-9 options. Code I71.4 is appropriate for an unruptured aneurysm of the abdominal aorta. ICD-10 also provides separate codes for a ruptured aneurysm (I71.3) and for aortic aneurysms in other locations (such as I71.2, Thoracic aortic aneurysm, without rupture).

Documentation: The physician’s documentation shouldn’t need to change to allow you to choose the proper ICD-10 code. You’ll need to know the location (thoracic, abdominal, thoracoabdominal) and whether the aneurysm ruptured so that you may choose the appropriate code from the range.

Coder tips: The diaphragm is the dividing line between the thorax and abdomen, so the thoracic aorta leaves the heart, arches, and descends through the chest until it reaches the diaphragm. The aorta becomes the abdominal aorta after it passes the diaphragm and continues down the abdomen.

Also be sure to distinguish between aneurysm, dissection (blood enters through a tear in the aorta’s lining into the space between the vessel’s middle and outer layers, causing a separation), and ectasia (enlargement milder than an aneurysm).

Remember: CMS has finalized the ICD-10 compliance date of Oct. 1, 2014. When ICD-10 goes into effect, you should apply the code set and official guidelines in effect for the date of service reported. Learn more at www.cms.gov/ICD10/ and www.cdc.gov/nchs/icd/icd10cm.htm#10update.