Procedural Determinants of Aspiration Thrombectomy Performance in Femoral and Iliac Artery Models: An In Vitro Study.

BACKGROUND

Procedural choices during aspiration thrombectomy (AT) for lower-extremity arterial thrombosis remain insufficiently quantified. We used an in vitro circulation model to assess how key procedural factors affect AT performance and safety-relevant end points.

METHODS

A lower-extremity arterial model simulated femoral and iliac thrombosis. Using a standardized thrombus model and the Indigo aspiration platform, we compared catheter diameters (6Fr, 8Fr, and 10Fr), guidewire retention versus removal, aspiration direction (antegrade versus retrograde), and separator use under predefined conditions. Each configuration was tested in 6 independent runs per catheter size. Outcomes (compared across the evaluated procedural conditions) included aspiration efficiency (unitless fraction of thrombus mass removed: [pre-post]/pre), blood loss (aspirated volume, mL), catheter obstruction, and distal embolization.

RESULTS

Catheter diameter significantly affected efficiency and blood loss in both femoral (efficiency, 6Fr vs. 10Fr: 0.41 [0.36-0.49] vs. 1.00 [0.69-1.00], P = 0.003; blood loss: 12.5 ± 9.35 vs. 185.0 ± 89.61 mL, P = 0.004) and iliac models (0.47 [0.31-0.65] vs. 0.94 [0.93-0.94], P = 0.002; 14.17 ± 7.36 vs. 333.33 ± 24.22 mL, P < 0.001). Distal embolization occurred only with 10Fr in the femoral model (4/6, 66.7%; P = 0.015). Within the same catheter size, blood loss was lower with guidewire retention than with guidewire removal, including 8Fr (5.00 ± 4.47 vs 22.50 ± 10.84 mL, P = 0.026) and 10Fr (19.17 ± 17.15 vs 185.00 ± 89.61 mL, P = 0.006). Aspiration direction showed no significant differences in efficiency or blood loss. The separator relieved catheter-tip occlusion and restored an aspiration pathway.

CONCLUSION

In this in vitro model, AT outcomes varied with procedural factors. Larger catheter diameter increased efficiency but also increased blood loss, and distal embolization was observed only in the 10Fr femoral group. Guidewire retention reduced efficiency, whereas aspiration direction had minimal impact. The separator was effective for relieving catheter-tip occlusion.