Myocardial protection by retrograde cardioplegia in arterial switch operation

Retrograde coronary sinus perfusion of cold cardioplegic solution was evaluated in infants undergoing an arterial switch operation for transposition of the great arteries. To assess myocardial injury during ischemia, hemodynamic measurements were conducted at weaning from cardiopulmonary bypass and a postoperative assay of creatine kinase isoenzyme MB was performed. In 22 infants with retrograde coronary sinus perfusion, the initial cardioplegic infusion was performed through the aortic root and additional infusion was repeated every 30 minutes by retrograde coronary sinus perfusion. The other 11 infants received additional solution by antegrade selective coronary artery perfusion. The aortic cross-clamp time in the retrograde coronary sinus perfusion group was significantly shorter than that in the antegrade selective coronary perfusion group (128 ± 19 versus 143 ± 21 minutes, p < 0.05). There were no significant differences between the two groups in terms of postoperative hemodynamic variables and enzyme indexes. Eight neonates in the retrograde coronary sinus perfusion group also exhibited enzymatic and hemodynamic indexes similar to those of the older infants. These results suggested that retroperfusion of cardioplegic solution was a safe and useful means of myocardial protection in infants and neonates because of the simplification of the operative procedure and the avoidance of traumatic injury to the coronary ostia.