Mechanical rotational thrombectomy in long femoropopliteal artery and bypass occlusions: risk factors for periprocedural peripheral embolization.

PURPOSE: We aimed to examine lesion characteristics influencing technical outcome and periprocedural peripheral embolization (PPE) during percutaneous mechanical rotational thrombectomy (PMT) of long femoropopliteal artery and bypass occlusions. METHODS: Retrospectively, 65 consecutive patients (43 male patients, mean age 70±12 years; Rutherford category I-III), undergoing PMT (Rotarex®, Straub Medical AG) with acutely/subacutely occluded femoropopliteal arteries/bypasses were included. Occlusions (mean length, 217±98 mm) were treated by PMT followed by percutaneous transluminal angioplasty (PTA) plus drug-coated balloon or PTA plus stenting/stentgrafting. Technical success was defined as residual stenosis <30%. Follow-up included duplex ultrasound and ankle-brachial index (ABI) after 12 months. Endpoints were technical success, complications, improvement of Rutherford category, ABI, and patency (re-stenosis <50%). The influence of lesion length, duration, and thrombus density (measured in preinterventional computed tomography angiography) on technical success and PPE was analyzed. RESULTS: Technical success was 18% (12/65) after PMT alone, 92% (60/65) after additional means. Four patients (6%) underwent bypass surgery and one patient (2%) amputation. PPE occurred in 11% (7/65). During the 12-month follow-up, three patients (5%) were lost to follow-up. ABI increased from baseline 0.5±0.12 to 0.81±0.14 (p = 0.001) and Rutherford category increased by at least one level in 57 patients at 12-month follow-up (clinical success, 88%). At 12 months, primary patency was 57.4% (95% CI, 45.8%-68.9%) and secondary patency was 75.0% (95% CI, 59.8%-72.3%). As risk factors for PPE, we identified lesion length >200 mm (15%; 6/39; OR 4.5; 95% CI, 0.5-40; p = 0.014) and thrombus density ≤45 HU (20%; 2/10; OR 3.0; 95% CI, 0.2-38.9; p = 0.05). No significant relation between risk factors and technical success was found. CONCLUSION: PMT followed by PTA or implantation of stent (grafts) appears to be effective and safe for revascularization of acute/subacute long occlusions. Thrombus density <45 HU and lesion length above 20 cm represent risk factors for PPE during PMT.