Short-term performance of Symvess (acellular tissue engineered vessel-tyod) compared to external control data for autologous vein in treatment of extremity arterial injury.

Background: To evaluate the short-term clinical performance of Symvess (acellular tissue engineered vessel-tyod), formerly known as human acellular vessel, or HAV, compared with autologous vein for the treatment of extremity arterial injury. Methods: Subjects treated with acellular tissue engineered vessel (ATEV) from two clinical trials were propensity score-matched on a 1:2 basis to PROspective Observational Vascular Injury Trial (PROOVIT) registry subjects with the same injured artery and treated with autologous vein. Matching characteristics included age, sex, trauma type (penetrating vs blunt), injury severity score, mangled extremity severity score, concomitant fracture, shunt use, and ischemia duration>6 hours. Incidence of outcomes (primary/secondary patency, amputation, conduit infection, reintervention for thrombosis/stenosis, pseudoaneurysm, and death) was assessed by a generalized linear model. Outcomes were assessed at Day 30 (ATEV group) or during initial hospitalization (autologous group). Results: ATEV subjects lacking suitable autologous vein (n=67) and PROOVIT subjects treated with autologous vein (n=134) suffered injuries to axillary, brachial, femoral, popliteal, and posterior tibial arteries. Subgroups were clinically similar; Injury Severity Score, Mangled Extremity Severity Score, and duration of follow-up (16 vs 30 days) were higher for the ATEV subgroup.Primary patency for the ATEV versus autologous group was 86.6% versus 91.8%, secondary patency: 91.0% versus 97.7%; amputation: 7.5% versus 8.2%; conduit infection: 1.5% versus 0%; reintervention for thrombosis or stenosis: 6.0% versus 8.2%; and death 4.5% versus 4.5%, respectively. No cases of pseudoaneurysm, true aneurysm, or significant differences between the ATEV and autologous groups for any outcome were observed. Conclusions: Short-term outcomes were similar between ATEV subjects without feasible autologous vein, and propensity score-matched autologous vein recipients from the PROOVIT registry. The ATEV may provide effective and safe revascularization in subjects with extremity arterial injury without feasible autologous vein. Level of evidence: Level 3, Therapeutic/Care Management.