I72.4

Aneurysm of artery of lower extremity

An aneurysm of the artery of the lower extremity refers to a localized, permanent dilation of a peripheral artery in the leg, typically defined as an increase in diameter of at least 50% compared to the normal vessel segment. The popliteal artery is the most common site for peripheral aneurysms, accounting for approximately 70% to 80% of cases, followed by the femoral artery. Unlike abdominal aortic aneurysms (AAA), which carry a primary risk of catastrophic rupture, lower extremity aneurysms are predominantly associated with thromboembolic complications. Thrombus formation within the aneurysmal sac can lead to distal embolization, often referred to as 'blue toe syndrome,' or acute arterial occlusion, which poses an immediate risk of limb-threatening ischemia and potential amputation. These aneurysms are frequently bilateral and are often associated with concurrent abdominal aortic aneurysms, requiring systemic vascular surveillance.

Clinical Symptoms

  • Pulsatile mass in the groin (femoral) or behind the knee (popliteal)
  • Acute limb ischemia (pain, pallor, pulselessness, paresthesia, paralysis, and coldness)
  • Intermittent claudication (leg pain during walking)
  • Distal embolic phenomena (painful, blue or purple toes)
  • Rest pain in the foot or toes
  • Swelling of the leg due to compression of adjacent veins
  • Numbness or tingling from compression of adjacent nerves
  • Non-healing ulcers or gangrene in the distal extremity

Common Causes

  • Atherosclerosis (most common underlying etiology)
  • Chronic hypertension
  • History of tobacco use (major risk factor)
  • Traumatic injury to the arterial wall
  • Iatrogenic injury following arterial catheterization or surgery
  • Infectious (mycotic) aneurysm, often secondary to endocarditis
  • Connective tissue disorders (e.g., Marfan syndrome, Ehlers-Danlos syndrome)
  • Cystic adventitial disease
  • Persistent sciatic artery (congenital anomaly)
  • Family history of aneurysmal disease

Documentation & Coding Tips

Specify the exact anatomical location of the aneurysm within the lower extremity to ensure maximum coding accuracy.

Example: Patient presents with a 3.2 cm fusiform aneurysm of the right popliteal artery. Billing Focus: Right side laterality and popliteal artery specificity. Risk Adjustment: Linked to HCC 108 (Vascular Disease) and documented as a chronic condition requiring surgical monitoring.

Billing Focus: Laterality (Right) and specific vessel (Popliteal Artery).

Document the presence or absence of thrombosis or distal embolization associated with the aneurysm.

Example: Left common femoral artery aneurysm, 2.8 cm, currently stable without evidence of mural thrombus or distal blue toe syndrome. Billing Focus: Left laterality and common femoral segment. Risk Adjustment: Absence of acute complication (thrombosis) reduces immediate risk score but maintains chronic vascular HCC status.

Billing Focus: Laterality and vessel segment (Common Femoral).

Distinguish between a true aneurysm and a pseudoaneurysm resulting from trauma or procedure.

Example: True aneurysm of the right superficial femoral artery, not related to recent catheterization. Billing Focus: I72.4 for true aneurysm versus I77.0 for acquired AV fistula or other codes for pseudoaneurysm. Risk Adjustment: True aneurysms are categorized differently for surgical planning and risk scoring than post-procedural complications.

Billing Focus: Etiology (True vs. Pseudo).

Include size measurements and growth rates in clinical notes to support medical necessity for intervention.

Example: Right popliteal artery aneurysm has increased from 1.8 cm to 2.3 cm over 12 months. Billing Focus: Progression supports medical necessity for more frequent duplex scanning. Risk Adjustment: Higher risk score associated with rapid expansion and potential for acute limb ischemia.

Billing Focus: Medical necessity for diagnostic imaging frequency.

Record comorbid peripheral arterial disease and smoking status which influence the complexity of care.

Example: Left femoral artery aneurysm in a patient with significant peripheral arterial disease (I70.212) and current cigarette smoking (F17.210). Billing Focus: Multiple diagnostic codes for vascular complexity. Risk Adjustment: Significant increase in risk adjustment score due to dual HCC status (Vascular Disease and COPD/Smoking complications).

Billing Focus: Co-occurring vascular conditions and social determinants of health.

Relevant CPT Codes

Related Diagnoses

Hierarchy