Direct transpedal pressure measurement during transpedal below-the-knee interventions in critical limb ischemia

The aim of this study was to assess the feasibility of the distal pressure measurement during transpedal below-the-knee interventions in chronic limb-threatening ischemia (CLTI) and to assess the hemodynamic response after percutaneous transluminal angioplasty.

The clinical and angiographic data of 137 consecutive patients treated via transpedal access in CLTI (Rutherford 4-6) were evaluated. Distal pedal pressure (PP) at the end of the pedal sheath was measured and the pedal-to-aortic pressure index (PAPI) was also calculated before and after the intervention.

Good angiographic results was achieved in 131 patients (95.6%) in the femoro-popliteal and at least in one below-the-knee artery. Significant differences were found in PP and PAPI between before- and after-intervention values (103.2 ± 41.6 mmHg vs. 138.2 ± 37.8 mmHg and 0.74 ± 0.29 vs. 1.03 ± 0.34), respectively. Post-procedural PP and PAPI were significantly higher in patients who underwent good and borderline/unsuccessful intervention 141.7 [135.8-147.6] versus 82.6 [33.8-131.5] mmHg and 1.05 [1-1.1] versus 0.53 [0.2-0.8], respectively. PP's are significantly different in various Rutherford classification groups. Among the studied parameters, postprocedural PAPI was found to have the best discriminatory power to predict 3-month amputation (c-statistic: 0.749, 95% CI: 0.546-0.952, p = .016, sensitivity: 57.1%, specificity: 92.3% using the cut-off criterion ≤0.58). Major adverse event was detected in 17 patients at 3 months follow up (12.4%), including 7 major amputations (5.1%).

Transpedal pressure and pedal-to-aortic pressure index significantly increased during transpedal below-the-knee angioplasty and final pressure and index correlates significantly with limb salvage.