Biological effect of orbital atherectomy and adjunctive paclitaxel-coated balloon therapy on vascular healing and drug retention: early experimental insights into the familial hypercholesterolaemic swine model of femoral artery stenosis

Aims: The efficacy of paclitaxel-coated balloons (PCB) for the treatment of superficial femoral artery (SFA) disease has been demonstrated in the clinical setting. Due to the high frequency of arterial calcification found in this vascular territory, the adjunctive use of atherectomy plus PCB has been proposed. In this study, we aimed to evaluate the biological effect on vascular healing and drug retention of this combination approach in the familial hypercholesterolaemic swine (FRS) model of femoral artery stenosis. Methods and results: Eleven femoral arteries (six superficial and five profunda arteries) were included. Vessels were injured (x2) over a 28-day period and all animals were maintained on a high cholesterol diet for 60 days following initial injury. Vessels were randomised to PCB (n=5) or orbital atherectomy system (OAS) plus PCB (n=6). At 28 days following therapy, vessels were followed with angiography, intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Vessels were harvested for histological and pharmacokinetic analysis. Angiographic findings were comparable at termination between both groups. The OCT findings were comparable at termination. There were no differences in the vascular healing profile between both groups. The paclitaxel levels at termination were comparable between both groups (PCB=5.16 vs. OAS+PCB=3.03 ng/mg). Conclusions: In the experimental setting, the combination of OAS+PCB appears to be safe by demonstrating a vascular healing profile and drug tissue levels comparable to PCB only. The vascular effect of PCB may be enhanced by the use of OAS by decreasing plaque burden and cholesterol crystals.