Interpretation of arterial duplex testing of lower-extremity arteries and interventions.

Arterial duplex testing is used to evaluate patients with lower-limb arterial occlusive or aneurysmal disease to provide clinicians with detailed information on location, extent, and severity of disease. It is possible to detect disease from the visceral aorta to the tibial arteries. Duplex testing is interpreted in conjunction with limb-pressure measurements to accurately categorize arterial hemodynamics and functional impairment. Understanding the features of duplex-acquired velocity spectra recordings is fundamental to accurate diagnostic testing, including the characteristic spectral features of "normal" versus "abnormal" lower-limb arterial flow, hemodynamic changes associated with stenosis or occlusion, and the status of distal limb or foot perfusion. Scanning can provide an arterial map of occlusive or aneurysm lesions analogous to an angiogram. Testing is accurate before and after intervention for the detection of stenosis; a common failure mode after bypass grafting or peripheral angioplasty. The detection of high-grade stenosis in an arterial repair allows for pre-emptive treatment before thrombosis occurs and improves long-term patency.