What are the diagnostic criteria for femoral artery stenosis?

From the Guidelines

Femoral artery stenosis is best diagnosed through a combination of clinical evaluation and imaging studies, with duplex ultrasound being the recommended first-line imaging test, as stated in the 2024 ESC guidelines 1. The initial assessment should include a thorough history focusing on claudication symptoms, physical examination with pulse palpation, and ankle-brachial index (ABI) measurement.

• An ABI below 0.9 strongly suggests peripheral artery disease.
• Clinical evaluation encompassing history, review of symptoms, and physical examination are the first steps in diagnosing and assessing patients with peripheral arterial and aortic diseases, as recommended by the 2024 ESC guidelines 1.
• For more detailed anatomical assessment, CT angiography (CTA) or magnetic resonance angiography (MRA) may be performed, with CTA offering superior spatial resolution but requiring iodinated contrast, as suggested by the 2016 AHA/ACC guideline 1.
• In cases where intervention is planned, digital subtraction angiography remains the gold standard, allowing for simultaneous diagnosis and treatment through balloon angioplasty or stenting.
• Early diagnosis is crucial as femoral artery stenosis can lead to significant morbidity including critical limb ischemia if left untreated.
• Risk factor modification including smoking cessation, diabetes management, and lipid control should be initiated immediately upon diagnosis to prevent disease progression. The 2024 ESC guidelines 1 also recommend laboratory assessments, including lipid profile, fasting glycaemia, glycated haemoglobin (HbA1c), renal function, blood count, coagulation studies, liver function, electrolytes, and inflammatory markers.
• Bilateral arm blood pressure measurement is recommended to assess for any significant differences in blood pressure between the two arms.
• Additional evaluations, like thyroid function tests, are advised as needed.

From the Research

Diagnosis of Femoral Artery Stenosis

• Femoral artery stenosis can be difficult to diagnose, but various imaging techniques are available to aid in diagnosis, including arteriography 2, Doppler ultrasound, digital subtraction angiography (DSA) 3, and tomographic 3D ultrasound (t3DUS) 4.
• The choice of imaging technique depends on the severity of symptoms and the presence of other medical conditions.
• Duplex ultrasonography, magnetic resonance angiography, and computed tomography angiography are also used for diagnosis and assessment of symptomatic lower limb peripheral arterial disease 5.

Imaging Techniques

• Arteriography is considered the gold standard for diagnosing femoral artery stenosis, but it is an invasive procedure 2.
• Doppler ultrasound is a non-invasive technique that uses sound waves to measure blood flow and detect stenosis 3.
• DSA is an imaging technique that uses X-rays and contrast agents to visualize blood vessels and detect stenosis 3.
• t3DUS is a reliable imaging technique for measuring vessel stenosis and can provide precise measurements of superficial femoral artery stenosis 4.

Diagnostic Criteria

• The peak systolic velocity (PSV) and velocity ratio are used to diagnose and grade stenosis of the superficial femoral artery 6.
• The correlation between blood flow velocity ratio and the degree of stenosis measured using Duplex 2DUS and t3DUS is strong 4.
• The established criteria for grading superficial femoral artery stenosis include PSV and velocity ratio thresholds 6, 4.

Comparison of Imaging Techniques

• Contrast-enhanced magnetic resonance angiography has the highest diagnostic accuracy for detecting stenosis of 50% or more in a lower limb vessel 5.
• Computed tomography angiography and duplex ultrasonography also have high diagnostic accuracy, but may not be as sensitive or specific as magnetic resonance angiography 5.
• The choice of imaging technique depends on the individual patient's needs and medical history 5.