Objective: To compare the safety and efficacy of percutaneous mechanical thrombectomy (PMT) and catheter-directed thrombolysis (CDT) in treatment of acute arterial thrombosis of the lower extremity. 
Methods: The clinical data of 67 patients undergoing endovascular interventional therapy for acute arterial thrombosis of lower extremity from July 2015 to March 2018 were retrospectively analyzed. Of the patients, 
37 cases received PMT treatment (PMT group), and 37 cases received CDT treatment (CDT group). The main perioperative variables between the two groups were compared.
Results: There were no significant differences in preoperative variables, the number of cases requiring further balloon dilatation and stenting after respective operation, primary revascularization rate and 12-month primary vascular patency rate between the two groups of patients (all P>0.05). In PMT group compared with CDT group, the average length of hospital stay was significantly decreased [ (5.8±0.8) d vs. (8.9±0.6) d, P<0.05], while the average hospitalization cost was significantly increased [ (70 000±11 000) yuan vs. (48 000±8 000) yuan, P<0.05]. No significant differences were noted in incidence of severe bleeding, postoperative amputation, puncture site hematoma, puncture site infection and renal insufficiency between the two groups (all P>0.05), but the overall incidence of complications in PMT group was significantly lower than that in CDT group (5.4% vs. 26.7%, P<0.05). 
Conclusion: PMT is as safe and effective as CDT in treatment of acute arterial thrombosis of the lower extremity, the incidence of complications and length of hospital stay are decreased, but hospitalization cost is increased in PMT compared to CDT.