How is bypass graft patency typically surveilled?

• A. Regular duplex ultrasound to evaluate graft velocity, diameter, and presence of postoperative stenosis or occlusion, supplemented by clinical assessment
• B. CT angiography annually without prior ultrasound
• C. MRI only if symptoms arise
• D. No routine surveillance

Answer: (A)

Regular duplex ultrasound is used to surveil bypass graft patency because it directly assesses how blood is flowing through the graft and the graft’s diameter, allowing detection of hemodynamically significant stenosis or early occlusion before symptoms appear. By measuring flow velocity, velocity ratios, and visualizing the graft’s lumen, duplex ultrasound can flag narrowing or blockage early. This functional information, when combined with a careful clinical check of pulses, limb perfusion, and symptoms, gives a reliable picture of graft health and helps guide timely intervention if needed.

Other approaches aren’t used as routine surveillance. CT angiography, while excellent for anatomy, exposes the patient to radiation and contrast and is less practical for regular monitoring. MRI is typically reserved for specific questions or when symptoms arise rather than for routine follow-up. Not performing routine surveillance misses early problems, increasing the risk of late graft failure.