A Case of Intraoperative Iatrogenic Aortic Dissection during Off-Pump Coronary Artery Bypass Grafting

A 70-year-old woman diagnosed with angina pectoris was scheduled to undergo off-pump coronary artery bypass grafting (OPCAB) using the left internal thoracic artery and the saphenous vein (SVG). We performed a proximal anastomosis of the SVG to the ascending aorta using a clampless proximal anastomotic device. When this device was removed from the ascending aorta after completion of the SVG proximal anastomosis, we noticed the extensive appearance of an ascending aortic adventitial hematoma. Transesophageal echocardiography revealed a flap in the ascending aorta, which was diagnosed as an iatrogenic aortic dissection. The decision was made to immediately perform an additional aortic replacement. There was an intimal tear consistent with the device insertion site, which was identified as the site for the development of aortic dissection. After performing an ascending aortic replacement, coronary artery bypass grafting was performed. Her postoperative course was uneventful, and enhanced CT on postoperative day 12 showed aortic dissection up to the level of the abdominal aorta, but the false lumen was completely thrombosed. Iatrogenic aortic dissection caused by proximal anastomotic device during OPCAB is a very rare but serious complication, and early intraoperative diagnosis and prompt additional surgical treatment were considered necessary to save the patient's life.