Aims: Vascular closure device (VCD)-based venous closure has been anecdotally reported, but systematic evaluation of the reparative response of the vessel wall to venous closure is lacking. The need to control groin complications, and minimize risks associated with postponed sheath removal under conditions of persistent anticoagulation, has generated interest in the role of VCDs for venous access closure. We sought to characterize the vessel wall response to venous closure, both acutely and in delayed fashion at 30 days using angiography, ultrasound, and histology.
Methods: Ten venous 7 Fr sheaths were deployed in the femoral veins of swine. Bilateral venous access sites were subsequently closed utilizing manual compression (MC; control arm: n = 4) or a closure device utilizing an extravascular polyethylene glycol sealant (MynxGrip treatment arm: n = 6). Acute (post closure), 3-day, and 30-day vascular ultrasound, as well as venography (internal jugular approach) were used to assess outcomes. Gross pathology and histology were obtained at the 30-day endpoint for all femoral venous closure sites.
Results: Hemostasis was successfully achieved in all cases without access-site complications. Venography and ultrasound confirmed normal ilio-femoral anatomy and flow at all study time points. Gross pathology and histopathology revealed no evidence of deep vein thrombosis, and no abnormalities were seen in the vena cava, heart, or lungs. Histology at 30 days showed complete healing of the vein wall access site, with a small focus of chronic inflammation and fibrosis in the perivascular adventitial tissue of the access tract. There was no microscopic evidence of the sealant. The tissue tract showed mild discrete inflammation (foamy macrophages, lymphocytes, plasma cells) with microgranulomas centered on residual red cells in both treatment and control groups.
Conclusions: This study characterizes the angiographic, ultrasound, and histopathology outcomes of femoral vein closure, and provides insight into the healing mechanisms following venotomy. The bio-resorptive role of MynxGrip extravascular sealant in achieving effective venous closure and preserved long-term vessel patency without venous thromboembolism is demonstrated.