Aspiration Thrombectomy with the Indigo System for Acute Lower Limb Ischemia: Preliminary experience and analysis of parameters affecting the outcome

Background: The purpose of our study is to assess the short-term technical success and the safety of the Indigo System in a series of patients undergoing vacuum-assisted catheter direct thrombus aspiration (IS-CDTA) for acute lower limb ischemia (ALLI) and to evaluate which parameters may affect the outcome. Methods: All procedures using the IS-CDTA for ALLI, performed in a single-centre Interventional Radiology Unit from February 2016 to March 2020, were retrospectively analysed. Technical success was defined as the achievement of nearly-complete or complete revascularization (TIPI grade 2/3) and considered as a good outcome. Variables potentially correlated with the IS-CDTA outcome were analysed. Results: 33 procedures were performed in 29 patients. Mean age was 69 years old (range 47 - 88), 24 males (83%) and 5 females (18%). The technical success was 70%. Catheter-directed thrombolysis following IS-CDTA was performed in 23 cases and the overall technical success increased from 70% to 90%, afterwards. The median time between symptoms insurgency and IS-CDTA was significantly shorter in patients with good outcome (10 hours; IQR 2.75-48) compared to those with poor outcome (168 hours; IQR 36-336) (P = 0.003). No statistically significant differences were found between the two groups regarding ATK vs. BTK (P = 0.34), native vessel vs. graft (P = 0.25), occlusion nature P = 0.28) or Rutherford score (P = 0.80). Conclusion: IS-CDTA is a valid option for a rapid and percutaneous treatment of ALLI. Our experience indicates that the time elapsing from the symptoms insurgency and the endovascular procedure is the best positive predictor of the outcome.