Objective: The purpose of this study is to evaluate the safety and efficacy of a novel 30 degrees end-to-side coronary anastomotic coupler (Converge Medical, Inc., Sunnyvale, CA) that facilitates a non-penetrating, sutureless vein graft to coronary artery anastomosis.
Material and methods: The Coupler utilizes a set of concentric mating frames approximating adjacent vessel tissue allowing for biological healing of the anastomosis. The frames are manufactured from Nitinol, a nickel titanium super-elastic metal alloy. The Nitinol frames attach the bypass graft to the coronary artery in a 30 degrees end-to-side configuration. Between November 2002 and March 2003 a total of 46 patients (44 male) with a mean age of 63.6+/-7.5 years were admitted for coronary artery revascularization and included in the study. The mean LVEF was 60.6+/-12.4%.
Results: Thirty-three patients were successfully treated with the Coupler. Nine patients did not meet the intraoperative inclusion criteria, and were excluded from the study due to small (<or=2.0mm) or severely calcified coronary vessels, or small vein grafts. Hemostasis could not be achieved with the Coupler in 3 patients, and in one patient the graft flow measured intraoperative was low. In these instances the Coupler was removed and the anastomosis was sutured without complication. Average mean flow rate using transit time method through the Coupler attached bypasses was 54+/-26ml/min. In a control angiography 2 months after surgery, 29 (96.7%) of the 30 connector grafts were patent. One stenosis of 50% occurred on the site of a connector anastomosis. Angiographic patency assessments for 81 hand sewn grafts revealed 73 (90.1%) patent grafts.
Conclusion: Initial results indicate that the Converge Coupler can be used to create a safe and effective 30 degrees vein graft to coronary artery anastomosis under suitable conditions.