Antegrade-Retrograde Cardioplegia for Myocardial Protection during Coronary Artery Bypass Graft Surgery

This prospective randomized clinical study was designed to assess and compare the use of combined antegrade-retrograde cardioplegia versus antegrade cardioplegia in providing adequate myocardial preservation during coronary artery bypass graft surgery. Fifty patients undergoing elective coronary artery bypass grafting were randomly divided into 2 groups according to the route of cardioplegic delivery: group A (25 patients) received antegrade cold crystalloid cardioplegia; group B (25 patients) received combined antegrade-retrograde cold crystalloid cardioplegia. The groups were compared by clinical and electrocardiographic criteria and biochemical markers of ischemic myocardial damage. There was a highly significant statistical difference between the groups in terms of spontaneous recovery of sinus rhythm (40% of patients in group A versus 96% in group B). The use of direct current shock to restore sinus rhythm was higher in group A (60%) compared with group B (4%). Low cardiac output occurred in 20% of patients in group A and in 16% of patients in group B but this difference was not statistically significant. No bundle-branch block was found in group B whereas the incidence was 8% in group A. Significantly higher levels of biochemical markers of myocardial damage were obtained in group A at 10 minutes, 4 hours, and 12 hours after declamping. These results indicate that combined antegrade-retrograde cardioplegia is superior to antegrade cardioplegia for myocardial protection during coronary artery bypass graft surgery.