Does Retrograde Administration of Cardioplegic Solution Improve the Clinical Outcomes in Primary Coronary Artery Bypass Grafting?

Background: The quality of myocardial protection during Coronary Artery Bypass Grafting (CABG) has a direct effect on post-operative cardiac function, recovery and complications. The optimal route for delivery of cardioplegia is still in debate in pa- tients with ischemic heart disease. 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. Methods: A total number of 150 patients that underwent CABG between 2009 and 2010 were assigned randomly into two groups according to myocardial protection technique; 75patients were randomly assigned to receive antegrade cold blood car- dioplegia (group A) and the other 75 patients received combined antegrade-retrograde cold blood cardioplegia (groupA/R). This prospective randomized study compared clinical, echocardiographic, markers of myocardial damage, morbidity and mortality in two groups. Results: The two randomization groups had similar demographic characteristics. The number of grafted coronary arteries averaged 3.2±0.4 in group A and 3.3±0.4 in group A/R. Total duration of cardiopulmonary bypass (64.1±23.2 and 66.3±16 minutes) and aortic cross-clamping (36.9± 13.7 and 34.6±8.6 minutes) were similar in both groups. There was one death in group A and one in group A/R, for a global early mortality of 1.3%. The cause of death was free wall LV rupture in group A and respiratory failure and pneumonia in group A/R. Release of total creatine kinase, creatine kinase–MB and troponin T were not significantly different (p 0.05) between the two groups. The number of postoperative myocardial infarction (12% versus 8%), the need for inotropic support (17.3% versus 12%), the need for IABP (2.7% versus 1.3%), post- operative arrhythmias (4% in each groups) were similar in both groups (P 0.05). Re- exploration, stroke, pulmonary complication, renal failure and wound infections also were similar (P 0.05). Conclusions: Our results indicate suggest that the retrograde cardioplegia administra- tion essentially does not improve myocardial protection during the first operation for isolated coronary revascularization compared with the usual antegrade route. The data indicate that in this non-risk-stratified group of patients, the route of cardioplegia ad- ministration is not a determinant of clinical outcome.