O-112 - USING A DEDICATED VENOUS MECHANICAL THROMBECTOMY DEVICE IN PATIENTS PRESENTING WITH ACUTE DEEP VEIN THROMBOSIS: AN INITIAL UK EXPERIENCE

TOPIC:
New vascular techniques and devices
AUTHORS:
Shah C. (Oxford University Hospitals NHS Foundation Trust ~ Oxford ~ United Kingdom) , Wilton E. (Oxford University Hospitals NHS Foundation Trust ~ Oxford ~ United Kingdom) , Wigham A. (Oxford University Hospitals NHS Foundation Trust ~ Oxford ~ United Kingdom)
Introduction:
Interventional treatment of deep vein thrombosis requires effective thrombus clearance and venoplasty / stenting of underlying stenoses. Mechanical techniques for thrombus clearance mitigate potential bleeding risks, and can enable single-sitting treatment. Limitations with current mechanical devices include embolization, poor thrombus and luminal clearance, and limited efficacy on sub-acute thrombus. We audit our results in treating acute and sub-acute deep vein thrombosis using the Inari Medical ClotTriever mechanical thrombectomy device in our tertiary vascular centre.
Methods:
Prospective data for all cases of venous mechanical thrombectomy using the Inari Medical ClotTriever device in our tertiary referral centre between March 2021 and March 2022 was collected.
Results:
15 patients (median age 50 years) have undergone treatment with the Inari Medical ClotTriever mechanical thrombectomy device in our centre between March 2021 and March 2022. The estimated mean age of thrombus, based on the patient's history, was 14 days (range 2-34 days). 12 of the cases had a unilateral iliofemoral distribution of venous thrombosis. 2 cases had bilateral iliofemoral venous thrombosis extending into the infrarenal IVC. No patients received additional lytic infusion therapy. Only 47% of procedures were undertaken under general anaesthesia. The median number of device passes was 6 (range 2-14). Mean thrombus clearance was 85% (range 80-90%). Stenting for underlying venous stenosis was completed in the same sitting in 11 cases. In those, a mean of 1.6 stents (range 1-4) were placed. The median procedure time was 115 minutes (range 45-210 minutes), and the median screening time was 31 minutes (15-79 minutes). The primary assisted patency rate was 86% thus far. 1 patient underwent re-intervention with venoplasty for in-stent thrombosis. There was acute re-occlusion at 6 weeks in one case, where re-intervention has been avoided due to minimal symptomatology. We have had no device-related or procedural complications.
Conclusion:
Preliminary data has shown that the Inari Medical ClotTriever mechanical thrombectomy device offers a single-sitting, thrombolytic-free mechanism for treating patients with an acute, or sub-acute, deep vein thrombosis that is not associated with any major access site complications, including bleeding, despite the increased sheath size. It is well tolerated, with over half of procedures completed successfully under local anaesthesia. The reduced incidence of stenting, particularly in the sub-acute patient group, is a promising early signal.