Risk factors for thromboembolic occlusions and efficacy of aspiration thrombectomy
A recent study from researchers at Shanghai Jiao Tong University has evaluated the predictive factors behind thromboembolic occlusions occurring during endovascular revascularization (EVR) and the success rate of percutaneous aspiration thrombectomy. A total of 260 patients underwent EVR. EVR was done using intraluminal and/or subintimal recanalization with 4000U heparin given prior to angioplasty. Uncovered self-expandable stents were placed in patients with flow-limiting dissections or residual stenosis. Of the 260 patients, 237 patients had restoration of flow without thromboembolic occlusion. 23 patients had EVR with subsequent thromboembolic occlusion. In patients with thromboembolic occlusion, a 5F or 6F guiding catheter was introduced and passed though the thromboembolic segment. A 20- or 50-mL syringe was connected to the guiding catheter after removal of the guide wire. After confirming adequate clot removal, 250,000–500,000 U urokinase was diluted in 50 mL saline solution and gradually infused into the treated artery to dissolve any remaining clots in all cases, even though no clots were present angiographically. Technical success was defined as <30% residual stenosis. Investigators report a technical success rate of 95.7% in the aspiration thrombectomy group. Interestingly, there were no significant differences in the clinical outcomes of the two groups including ABI, maximum walking distance, ulcer healing, restenosis/occlusion, and limb salvage rates. Further, there were few factors that could be cited as significant risk factors for thromboembolic occlusion during EVR including stenosis >90% and intraluminal angioplasty. The authors concluded that aspiration thrombectomy is an effective therapy for acute thromboembolic occlusion and may be considered primary treatment when this event occurs during infrainguinal arterial EVR.
Wei L, Zhu Y, Liu F, et al. Infrainguinal endovascular recanalization: risk factors for arterial thromboembolic occlusions and efficacy of percutaneous aspiration thrombectomy. J Vasc Interv Radiol 2016; 10.1016/j.jvir.2015.11.025
Luke R. Wilkins, MD