On-pump with beating heart or cardioplegic arrest for emergency conversion to cardiopulmonary bypass during off-pump coronary artery bypass

BACKGROUND AND OBJECTIVES: Intraoperative conversion, especially under emergent circumstances during off-pump coronary artery bypass (OPCAB), is associated with a significantly higher rate of hospital mortality. This study compared the clinical early outcomes of patients emergently converting to cardiopulmonary bypass (CPB) with or without cardioplegic arrest and evaluated the efficacy of an on-pump beating heart technique for these critically ill patients. DESIGN AND SETTINGS: A retrospective study of patients treated at The First Affiliated Hospital of China Medical University over an 8-year period (2005 to 2013). PATIENTS AND METHODS: Between January 2005 and September 2013, 104 patients were emergently converted to CPB during OPCAB. In the first 55 patients (53%), the cardioplegic arrest was performed. In the most recent 49 patients (47%), the on-pump beating heart procedure was used without cardioplegic arrest. RESULTS: There were no significant differences in their baseline clinical characteristics, number of anastomoses performed per patient, and reasons for conversions (P>.05). A significant reduction occurred in the observed mortality between the cardioplegic arrest group and the on-pump beating heart group (25.6% vs 6.1%, P=.008). A statistical difference was found between the cardioplegic arrest group and the on-pump beating heart group in the time of CPB, peak cardiac troponin I, duration of inotropic support, time to extubation, intensive care unit stay, postoperative hospital stay, incidence of new intra-aortic balloon pump support, and pulmonary complications (P<.05). The incidence of blood requirements, postoperative myocardial infarction, new-onset atrial fibrillation, hemodialysis, stroke, infective complications, and resurgery for bleeding were lower in on-pump beating heart group, but the difference did not reach statistical significance (P>.05). CONCLUSION: The on-pump beating heart technique is the preferred method of emergency conversion to CPB during OPCAB. It has lower postoperative mortality and morbidity than the cardioplegic arrest.