Hemodynamic collapse during off-pump coronary artery bypass grafting

Background. The causes of hemodynamic collapse during off-pump coronary artery bypass (OPCAB) remain scarcely defined. We present an analysis of 23 cases of sustained hemodynamic collapse during elective off- pump CABG. Methods. During a 54-month period, we performed 1420 elective OPCAB procedures through a sternotomy, constituting 71.2% of the total CABG procedures performed. Twenty-three patients (1.6%) experienced hemodynamic collapse intra-operatively requiring immediate cardiopulmonary bypass. Preoperative characteristics, intraoperative data, and postoperative outcome were retrospectively reviewed in each patient. Results. In all cases, improvements in intra-operative technique and/or judgment could be made retrospectively. Twenty (20/23) of these patients had an uneventful postoperative course and three (3/23) patients had an unstable course with two deaths. Conclusions. The causes of hemodynamic collapse during elective OPCAB were ischemic, mechanical, or a combination of both. A detailed review of our five and a half year experience has revealed a number of suggestions for improving the conduct of the operation.