Comparison of neurological outcomes in patients undergoing conventional coronary artery bypass grafting, on-pump beating heart coronary bypass, and off-pump coronary bypass

OBJECTIVE: To study the differences in the prevalence of neurological complications following coronary artery bypass (CAB) carried out by conventional, on-pump beating and off-pump techniques.

METHODS: A retrospective analysis of all isolated coronary bypass operations (n=127) performed in King Fahad Cardiac Center, Riyadh over a period of one year starting from January 2005. Out of 127 patients, 73 underwent conventional CAB graft (CABG), 33 patents on-pump beating heart coronary bypass, and 21 had off pump coronary bypass grafting (OPCAB). All patients had preoperative carotid scans and those who developed neurological complications underwent CT-brain and expert neuro-psychiatric assessment.

RESULTS: Preoperative characteristics of patients in all 3 groups were similar. The bypass times in the conventional CABG group were significantly longer than the on-pump beating group. The maximum number of grafts was in the on-pump beating group, followed by the conventional CABG, and the least in the OPCAB group. Seven out of 73 cases in the conventional bypass group developed neurological events of various severities. Only one out of 33 patients developed acute confusional state in the on-pump beating group and no neurological events were noticed in 21 patients operated by the OPCAB technique. Low ejection fraction, preoperative congestive cardiac failure, non-elective surgery and preoperative catastrophic state were found to be significant risk factors independent of the bypass technique.

CONCLUSION: This study shows no significant difference in the prevalence of neurological complications among different types of bypass surgery in our institution. There was a trend towards less neurological outcomes in the OPCAB and on-pump beating groups.