Abstract TP54: Result of Clinical Trial Using Tron Fx, New Stent Retriver for Acute Ischemic Stroke

Objective: To show safety and efficacy of mechanical thrombectomy (MT) for acute stroke using TRON-FX in Japanese approving trial. Material and Methods: This trial is multi center, prospective, single arm, registry study of new stent retriever, TRON-FX, Biomedical Solutions, Tokyo, Japan. TRON-FX have 2 size variation, 4mm diameter/20mm length and 2/15, smallest in the world. Inclusion criteria are 1) acute ischemic stroke (AIS) aged 20-85, 2) from onset to start MT within 8 hours, 3) IV rt-PA is ineligible or ineffective, 4) confirm occlude ICA, M1/M2/M3, VA, BA, and P1/P2. 5) NIHSS score 8 or more. Primary endpoint is immediate post procedural recanalization (up to 3 times by TRON-FX)and symptomatic intracranial hemorrhage (ICH) at 24 hours. Secondary endpoints are 1) good neurological outcome (mRS 0-2) at 90days, 2) symptomatic and asymptomatic ICH at 24 hours, 3) Mortality within 90days and 4) device-related or procedure-related serious adverse events at day 90. Results: 50 patients enrolled and first patient in was 2017/9/27 and last patient in was 2017/11/5. All patient followed 90 days. Median age is 75, raged 44-86, male gender is 62% (31/50), occluded vessels are ICA(2) 4%, MCA/M1(23) 46%, MCA/M2M3(26) 52%, BA(3) 6%, PCA(1) 2%, IV rt-PA failed(37) 74%, median baseline NIHSS score is 17, ranged 8-29, and median mRS prior to stroke 0. The primary endpoint, recanalization TICI 2b or better was 40(80%), and symptomatic ICH was 1(2%). More over, the secondly endpoint, 1) mRS 0-2 at 90 days was 25/47(53.2%), 2) symptomatic and asymptomatic ICH was 15(30%), 3) mortality was 4(8%) and 4) no device-related or procedure-related serious adverse event. Conclusions: TRON FX approving trial in Japan has proved great efficacy and safety of this thrombectomy device with high recanalization rate with less intracranial hemorrhage, especially for distal and small vessel. Clinical Trial gov. IDNCT02964702