Physiologic Guidance of Infrainguinal Vascular Interventions Using the Pressure Wire

To assess the relationship between the resting (RG) and hyperemic (HG) translesional peripheral gradients, with the functional and anatomic parameters before and after an infrainguinal endovascular procedure.

RGs and HGs are objective tools in defining the hemodynamic significance of an arterial stenosis.

In 25 subjects with infrainguinal arterial stenosis, RG and HG were measured via a pressure wire before and after angioplasty. Before and after the procedure, all subjects had an ankle-brachial index (ABI) and Duplex ultrasound evaluation, recording prelesion and in-lesion peak systolic velocity (PSV-L), and calculating a peak systolic velocity ratio (PSV-R). A Pearson R correlation coefficient was calculated.

The mean age was 73 ± 12 years, 70% were men, median Rutherford class 3. At baseline and after angioplasty, mean ABI was 0.78 ± 0.2 and 0.99 ± 0.1, mean PSV-L was 459 ± 110 cm/s and 126 ± 35 cm/s, and mean PSV-R was 6.7 ± 4 and 1.2 ± 0.5, respectively. RG and HG significantly improved (P<.001) from baseline to after angioplasty (28.7 ± 20.5 mm Hg to 5 ± 13 mm Hg and 40.2 ± 21.4 mm Hg to 10 ± 13 mm Hg, respectively). RG before and after the procedure correlated well with ABI (r = -0.58; r = -0.41), PSV-L (r = 0.40; r = 0.52), and PSV-R (r = 0.46; r = 0.42). An improvement of 9 mm Hg in RG predicted a change of 0.1 in ABI.

Improvement in RG during endovascular intervention in superficial femoral artery correlates well with the improvement in ABI, PSV-L, and PSV-R. A postprocedural decrease in RG of 9 mm HG predicts an improvement in ABI of 0.1.