Efficacy of intraoperative epiaortic ultrasound scanning for preventing stroke after coronary artery bypass surgery.

PURPOSE The aim of this study was to clarify the efficacy of intraoperative epiaortic ultrasound scanning (EAS) for preventing cerebral emboli following coronary artery bypass grafting (CABG). PATIENTS AND METHODS The intraoperative EAS was used to evaluate the ascending aorta in 909 consecutive CABG patients. When the scanning documented more than 3 mm of atheromatous thickness or plaque in the ascending aorta, we never manipulated it. Therefore 196 patients (21.6%) underwent off-pump CABG using composite grafts (85 cases, 9.4%) or in situ grafts (111 cases, 12.2%) with no aortic manipulation. The ascending aorta was confirmed to be free from significant atheromatous plaque by the EAS in 713 patients (78.4%). On-pump CABG was performed using aortic cannulation and total aortic clamping in 429 patients (47.2%). Off-pump CABG with aortocoronary bypass grafts was performed using side-bite aortic clamping in 165 cases (18.2%) or the other anastomotic devices in 63 cases (6.9%). RESULTS There were five hospital deaths (0.6%) but no postoperative strokes. Postoperative coronary angiography revealed 98.8% (1,659/1,680) of the patency of the bypassed grafts. CONCLUSIONS It was suggested that the application of aortic clamping or cardiopulmonary bypass was not a risk factor of cerebral emboli when the ascending aorta was evaluated using the EAS. Furthermore, the application of aortic clamping with free grafts may provide eligible bypass graft patterns, leading to sufficient graft patency.