title: Cerebral Emboli Generation During Off-Pump Coronary Artery Bypass Grafting With a Clampless Device versus Partial Clamping of the Ascending Aorta.
abstract: OBJECTIVE
  : It is not known whether use of a clampless facilitating device during proximal graft anastamosis decreases intraoperative cerebral emboli in patients with mild atherosclerotic ascending aorta (AAA) having off-pump coronary artery bypass.
  
  
  METHODS
  : After intraoperative epiaortic ultrasound showed no more than mild (grade I-II) atherosclerotic ascending aorta, 20 patients were randomized to receive either partial clamping (PC, n = 10) or the HEARTSTRING clampless device (HS, n = 9) for proximal graft construction on the ascending aorta. Continuous transcranial Doppler monitoring, with capability to discern gaseous from solid particulates, was used intraoperatively to monitor high-intensity transient signals (HITS) in the middle cerebral arteries. Postoperative diffusion-weighted brain magnetic resonance imaging documented old and new ischemic brain lesions.
  
  
  RESULTS
  : There were no significant differences between the groups in the number of proximals (P = 0.14), distals (P = 0.4), or intraoperative cell saver transfusions (P = 0.69). The total number of HITS was not significantly different between the PC and HS groups (P = 0.2). However, the number of solid HITS was significantly lower in the HS than in the PC group (2.7 ± 2.6 versus 14.0 ± 8.1; P < 0.001). The number of gaseous emboli in the HS group was fourfold greater when a mister-blower rather than a suction device was used to clear blood away from the HS site. Postoperatively, there were no deaths, myocardial infarctions, or clinical strokes observed in either group. Diffusion-weighted cerebral magnetic resonance imaging revealed no statistical difference between groups for new infarct lesions.
  
  
  CONCLUSIONS
  : Use of the HS device during off-pump coronary artery bypass was associated with significantly fewer intraoperative solid emboli in the middle cerebral artery than PC of the ascending aorta.
authors.affiliation: From the Division of Cardiothoracic Surgery, Department of Surgery, Emory University School of Medicine, Atlanta, GA USA.
authors.forename: Shady M
authors.initials: SM
authors.lastname: Eldaif
authors.forename: Vinod H
authors.initials: VH
authors.lastname: Thourani
authors.forename: John D
authors.initials: JD
authors.lastname: Puskas