Clinical evaluation of the eSVS Mesh: First-in-Man trial outcomes

In coronary artery bypass graft surgery, saphenous vein graft (SVG) patency is much lower than that of the internal mammary artery (IMA). To address this problem, an external support device, the eSVS Mesh was developed. A prospective randomized First-in-Man feasibility trial was conducted in 90 patients after institutional ethics committee approval at seven international centers. The left IMA was used to bypass the anterior descending artery. A mesh-supported (treated) saphenous vein was randomized to either the right or the circumflex coronary system, and an unsupported (control) vein was grafted to the opposing territory. Device diameters available for use were 3.0, 3.5, 4.0, and 4.5 mm. Primary end-points were 30 day adverse cardiac and cerebral events and angiographic patency at 9-12 months. Eighty-five of 90 patients returned for 30 day clinical follow-up (94%). Five patients refused to return, but by telephone contacts were asymptomatic. There was one late noncardiac death and 73 patients returned for angiography (82%), thus 12 additional patients were lost to follow-up at 1 year. Overall patency rate was 49% for the treated versus 81% for controls (p < 0.001). Subset analysis revealed significantly lower patency at one center and with use of the 3.0 mm device (p < 0.05). Removing these data, patency was 72% vs. 81% (p = NS). Sternal wound infection was higher than expected at 5.0%, but this was center specific. The eSVS Mesh is safe, but at up to 1 year, patency is equivalent to untreated vein grafts after removal of outlying data. This study provides insight into operative events and parameters that may optimize outcomes and point to potential improvements in the external SVG support device. Furthermore, longer term studies are pending.