Duplex ultrasound imaging to detect limb stenosis or kinking of endovascular device

Objective: We attempted to correlate duplex ultrasound (DU) findings with the clinical outcome of graft limb stenosis or kinking after endovascular aneurysm repair (EVAR). Methods: Between 1998 and 2010, 248 patients underwent EVAR and postoperative DU surveillance of 496 graft limbs in our accredited noninvasive vascular laboratory by one of three experienced technologists. Routine DU surveillance was performed 1 week, 6 months, and annually after EVAR. Peak systolic velocities (PSVs) were measured in the body and midportion and distal attachment site of both limbs of the graft, and adjacent PSV ratios were calculated. Results: None of 479 graft limbs with a PSV of <300 cm/s occluded during long-term follow-up (mean, 22.3 months; range, 1-123 months). Of 17 graft limbs with a PSV >300 cm/s, seven occluded (0 of 479 vs 7 of 17, P <.01; sensitivity, 100%; specificity, 98%), five underwent prophylactic intervention (mean adjacent PSV ratio, 7.3), and five (30%) remained patent without intervention (mean PSV ratio, 3.2). Conclusions: This large series of DU surveillance for failing EVARs grafts suggests that graft limbs with PSVs <300 cm/s can be safely monitored. However, limbs with more elevated PSVs may benefit from prophylactic intervention or more frequent surveillance to prevent limb occlusion.