What characteristic is often associated with popliteal artery aneurysms?

Characteristics of Popliteal Artery Aneurysms

Popliteal artery aneurysms are more common than femoral aneurysms, are often bilateral (occurring in approximately 50% of cases), predominantly affect males (95-99% of cases), and frequently result in limb ischemia with a high risk of thromboembolic complications. 1

Epidemiology and Prevalence

• Popliteal artery aneurysms account for 70% of all peripheral aneurysms in the lower extremities 1
• They have an estimated incidence of 0.1% to 2.8% in the general population 1
• Strong male predominance (95-99% of cases) due to men's predisposition for arteriosclerosis 2
• Approximately 50% are bilateral, which serves as an important diagnostic clue when evaluating patients with acute limb ischemia 1, 2
• 30-50% of patients with popliteal aneurysms also have abdominal aortic aneurysms 2

Clinical Presentation and Complications

• Up to 75% of popliteal artery aneurysms are discovered in symptomatic patients 3
• Symptoms include:
  • Arterial insufficiency
  • Leg swelling
  • Pain in the popliteal fossa
  • Acute limb ischemia
• Thromboembolic complications are common and serious:
  • 36% of patients with observed popliteal aneurysms develop complications 1
  • Cumulative incidence of ischemic complications reaches 70% during 5-10 years of follow-up 1
  • Even after surgical repair of symptomatic aneurysms, 56% of patients may continue to experience distal ischemia 1
  • Amputation rates of 19% have been reported 1

Diagnosis

• Ultrasound is the initial diagnostic test of choice 1
• Patient positioning in reverse Trendelenburg or semi-sitting position with 30° hip flexion optimizes examination 1
• A palpable popliteal mass should prompt ultrasound examination to exclude popliteal aneurysm 4
• The presence of a prominent popliteal pulse in the opposite leg can help identify the underlying etiology of acute ischemia 4, 1

Management

• Surgical indications:
  • All symptomatic aneurysms
  • Asymptomatic aneurysms ≥2.0 cm in diameter 4, 1
• Annual ultrasound monitoring is recommended for:
  • Asymptomatic aneurysms <2.0 cm 1
  • Asymptomatic enlargement of popliteal arteries twice the normal diameter for age and gender 4
• Treatment options:
  • Open surgical repair (conventional approach)
  • Endovascular stent grafting (for selected patients) 5
• In patients with acute ischemia and absent runoff, catheter-directed thrombolysis or mechanical thrombectomy should be considered to restore distal flow 4, 1

Common Pitfalls in Management

• Mistaking thrombosed popliteal aneurysm for an embolic event 1
• Failing to screen for contralateral popliteal aneurysms and abdominal aortic aneurysms 1
• Delaying treatment of asymptomatic aneurysms ≥2.0 cm 1
• Underestimating the risk of thromboembolic complications and limb loss 4

Popliteal artery aneurysms represent a significant risk for limb-threatening ischemia and potential limb amputation due to their propensity for thrombus formation, which can reduce blood flow to the leg. Early diagnosis and appropriate management are essential to prevent these serious complications.