Background and purpose The Mynx M5 (AccessClosure, Inc., Mountain View, California, USA), a novel vascular closure device (VCD) utilizing extravascular synthetic sealant, may effectively seal the arteriotomy while reducing the pain associated with arteriotomy closure seen with other VCDs. To date, no studies exist comparing the pain associated with deployment between differing VCDs as a primary end point.

Methods A blinded, randomized controlled trial was performed comparing the Mynx and a popular VCD that utilizes a self-tightening suture, the Angio-Seal Evolution (St Jude Medical, St Paul, Minnesota, USA). Subjects were all adult patients undergoing diagnostic cerebral angiography via femoral access. Local anesthesia and intraprocedural intravenous pain medication were standardized. Pain was assessed using a horizontal visual analog scale both before and after VCD deployment.

Results 64 patients were enrolled with 32 in each treatment arm. Both pain at closure and pain increase from baseline to closure were significantly higher in the Angio-Seal group (p=0.009 and 0.002, respectively). 88% of patients receiving an Angio-Seal reported closure as the most painful part of the procedure compared with only 34% of patients receiving the Mynx (p<0.001). No adverse events were detected in either treatment arm.

Conclusions In a blinded, randomized trial comparing the Mynx with the Angio-Seal Evolution, pain with device deployment at arteriotomy closure was significantly lower with the Mynx. The reason for the large pain gradient between groups is likely due to the presence, and absence, of compression elements within the Angio-Seal and Mynx, respectively.