Triple Aspiration Versus Conventional Aspiration Techniques: A Randomized In-Vitro Evaluation

BACKGROUND AND PURPOSE: A single aspiration maneuver using a large volume syringe is a common and effective technique for aspiration thrombectomy. Multiple aspiration cycles using large aspiration syringes has been proposed as a means to improve efficacy over single aspiration. In this study, we sought to investigate the efficacy of a “triple aspiration technique” where a large volume syringe is cycled three times prior to catheter retraction during aspiration thrombectomy.

MATERIALS AND METHODS: A 3D-printed adult vasculature was used as a benchtop thrombectomy platform. Fibrin-rich and red blood cell-rich clots were prepared in centrifuge tubes using human plasma, red blood cells, and calcium chloride. Next, clots were placed in the carotid terminus of the model, and the performances of three different aspiration techniques—triple syringe, single syringe, and continuous pump aspiration—were compared in a randomized manner (1:1:1). Outcomes of interest included first-pass efficacy (FPE), complete clot removal (final mTICI 2c/3), the number of thrombectomy attempts to achieve mTICI 2c/3, vacuum pressure, and distal embolization. The distal emboli were detected using a 70-micron cell strainer placed at the outflow of the model and quantified using an image processing algorithm. The vacuum pressures were measured using a pressure transducer (Honeywell, NC, USA).

RESULTS: A total of 102 replicates were performed, 34 for each technique. The triple aspiration technique provided a significantly higher rate of FPE than the syringe and pump aspiration techniques (67.6% vs. 41.1%, p= 0.02). Additionally, the triple aspiration technique achieved complete clot removal with a significantly lower number of thrombectomy attempts compared to single syringe aspiration (1.2 ± 0.5 vs. 1.8 ± 0.8, p=0.005). The triple aspiration technique generated significantly higher vacuum pressure than both the single syringe and vacuum pump aspiration (28.3 ± 0.2 vs. 27.2 ± 0.3 (p= 0.002) and 26.2 ± 0.4 (p=0.001), respectively). The differences in complete clot removal and distal embolization parameters were not statistically significantly different across the groups.

CONCLUSIONS: Our findings suggest that the triple aspiration technique can improve FPE rates and vacuum pressure in aspiration thrombectomy. Further studies are needed to examine the safety and efficacy of triple aspiration in the clinical setting.

ABBREVIATIONS: AcommA = anterior communicating artery; FPE = first pass efficacy; ICA = internal carotid artery; MCA = middle cerebral artery; MT = mechanical thrombectomy; mTICI = modified thrombolysis in cerebral infarction scale; PcommA = posterior communicating artery.