Pitfalls and key lessons with the symmetry proximal anastomotic device in coronary artery bypass surgery

Increasing practice of less-invasive coronary artery bypass surgery has generated a revival of automated methods to facilitate the creation of vascular connections during coronary artery bypass grafting procedures.

We have reviewed our clinical experience with 107 patients who received at least one proximal Symmetry aortic connector from St. Jude Medical Anastomotic Technology Group (St. Paul, MN) to connect a saphenous vein graft to the ascending aorta, in whom the minimal follow-up is 6 months. Seventy-five patients were part of an observational study, and 32 patients were enrolled in a prospective randomized study to compare the anastomotic device with the conventional suture technique. Key lessons and pitfalls observed during loading and deployment as well angiographic findings are presented.

Hospital mortality was 0.9% (1/107); a 76-year-old woman suffered from cerebral complications and died after combined coronary artery bypass grafting and aortic valve replacement. Two connectors had to be removed because of leakage and one because of incomplete deployment. The residual 104 grafts connected to the ascending aorta were patent at the end of the operation (mean flow, 72 +/- 29 mL/min). Fourteen patients from the prospective study have received 6 months of angiographic assessment so far. Forty-two grafts have been evaluated: all IMA grafts (n = 14) are patent. Four radial artery grafts have been studied: three are patent and one is occluded. Twenty-four vein grafts have been assessed: 11 were hand-sewn and 13 were connected to the aorta with the proximal connector system. Patency rate is not different between the two techniques, but there is an incidence of 38% (5/13) stenosis in the proximal vein graft segment in those patients with a proximal connector. No proximal hand-sewn anastomosis shows any significant stenosis.

The use of proximal devices allows ultrafast connection of a bypass graft to the aorta. The handling of this device is simple, manipulations on the ascending aorta are minimized, and hemostasis is perfect. However, because stenoses have been observed in the vein graft close to the connector site, mid- and long-term patency rates have to be assessed in large prospective trials.